qikqbn

Hey Andy,

this post was over a year ago, but here is the information I think you are looking for. You may already know this.

What you are referring to as LSD "limited slip differential" may also be confused with "ABD" automatic braking differential.

According to some of my very early 911/Boxster Porsche brochures and my own experience with Boxsters "ABD" automatic braking differential

this is how it works in a nutshell.

PSM Porsche stability Management while ON uses ABS, anti-slip regulation, an automatic brake differential and a battery of sensors

that monitors direction, pitch, speed, yaw velocity, and lateral acceleration. It will apply the brakes to individual wheels in order

to stabilize the vehicle based on what kind of slide/skid the car is in.

Included in PSM is the ASR anti slip regulator, and ABD. If one tire slips the automatic brake differential applies the brake to

the slipping tire, hence reacting and behaving just like a limited slip differential. If BOTH tires spin, then the ASR slip regulator

kicks in and retards the ignition and cuts power so that traction is regained.

Turning PSM OFF will disable the ASR, four corner braking montiors, and pitch/yaw sensors...... BUT the Automatic braking differential stays on at ALL times

up to 62 mph... That is why you will notice that even with the PSM OFF light showing you will still see a separate flashing warning light letting

you know that ABD is still kicking in during certain rear traction sliding situations to try and behave like a limited slip differential....

Hope this makes sense. It is pretty amazing programing that Porsche has developed. But nice to know you can turn it off if you are brave enough ;^)

hey spyder

I just installed a new ignition switch last night and have a similar issue. car starts fine and everything seems to work , BUT now my airbag light is on. it was never on before so it has to be something with the new part or something was knocked loose.

Can you give a few more specifics about what was not working for you and what exactly was not "lining up" ?? maybe we have similar connection issues.

did you also notice that it takes a little more effort to turn your key with the new part?....

my boxster is a 1998... I think I know what may have happened. I took the gauge cluster out for much easier access to ignition switch...

I tested the car to see if the ignition worked with out having the cluster and a couple other things plugged in... maybe that did it... now i need to get the code cleared... hmmmm... just a thought, but not sure...

thanks, Bill

Bill,

From what I have read I think your light may be coming on due to testing your switch without everything else hooked up. On mine I did not have the ignition switch in position 0. When my original piece failed it left my key stuck and I once I forced the key out I neglected to realign it before installing the new switch.

So mine was not lined up correctly when I tightened the set screws.

Yup, somehow I triggered it while testing the ignition without having everything plugged in. Swung by the dealership and they reset all my fault codes.

there were fault codes for the unplugged gauge cluster as well as the seatbelt/airbag sensor... All good now. another lesson learned...

take care.

Bill

Had trouble last week getting my key out of the ignition and noticed it no longer kicked back to on once started so I did a search and followed all of the advice in the DIYs.

Got the new piece in and changed them out this morning but ran into a pretty big issue, when I reconnected my battery and went to start the car I got the Airbag error and all other lights on, but the key would not turn. I have since disconnected the battery and removed the new part but does anyone have any ideas what might be wrong here? Do I reinstall it again and hope I somehow messed up the first time?

Any chance this airbag light wont come back?

I ordered the part from Autohauz and it is the Meyle unit. Has any else experience similar?

Okay, I took it out and reinstalled it and realized things were not lining up as necessary. Turned thrned the key back and forth a couple times and then reinstalled and all is well.

hey spyder

I just installed a new ignition switch last night and have a similar issue. car starts fine and everything seems to work , BUT now my airbag light is on. it was never on before so it has to be something with the new part or something was knocked loose.

Can you give a few more specifics about what was not working for you and what exactly was not "lining up" ?? maybe we have similar connection issues.

did you also notice that it takes a little more effort to turn your key with the new part?....

my boxster is a 1998... I think I know what may have happened. I took the gauge cluster out for much easier access to ignition switch...

I tested the car to see if the ignition worked with out having the cluster and a couple other things plugged in... maybe that did it... now i need to get the code cleared... hmmmm... just a thought, but not sure...

thanks, Bill

problem too!!!!!

Hmmm... Sometimes our wide performance tires will "wobble" a bit when still cold in the morning. As they warm up, tire pressure

increases, and they flex a bit which may help the wobbling go a way a bit....

I have had several tires by now and always experience a little wobble when cold.

-balancing would be my first guess.

-check tire pressures

-maybe "flat spot" from very hard braking or skid... (abs should have prevented that though)

-new tires would be my next guess. Be sure to check "inside edge" tread wear.. Porsche sets

up the alignment to wear out inside edge faster.. (especially on rears)

everything may look fine on outside edge even though tread is very low on inside...

-Did the previous owner use "wheel spacers"??? if so, make sure they are flush against

the rotor. One time the screw that holds rotor in place was not screwed in tightly and flush.

so when the wheel spacer was installed on my car the rotor screw was out just enough

to throw things off and cause a horrible wobble. took me several wheel balances to figure

that one out...

alignment might not be a bad idea, although alignments should not cause major wheel vibrations.. so I was told,

but you never know.

best of luck,

Bill

Cayenne S is the same.... but you should know like gdavison mentioned...

According to Porsche the Cayenne's , when cold starting, run in 1st for a few seconds. This is programmed into

the transmission computer in order to "warm up" the catalytic converters faster within the first few seconds....

Once Cats are hot, then 2nd gear is the default gear for starting accelleration from stop... No matter how aggressive

you drive... 1st gear can only be select with "manual mode" or flicking tip button to downshift at stop...

Personally, I really don't like driving our Cayenne S without using "manual mode" stick shift... my wife drives the car fairly

easy.. Then when i jump into it the transmission programing is for easy driving where I like to drive aggressively...

it never seems to learn fast enough for my driving style, so I automatically drive it like a manual all the time..

Then I can put it into first gear when ever I come to a stop... but that's me... my wife hates my driving .. haha..

Makes for a much funner experience if you ask me...

all the best

Bill

hey suburban99...

hmmm.. could be several things.... don't know how mechanically inclined you are but here are some suggestions to consider...

1. clean MAF sensor.... I use 90% rubbing alcohol... poor into cup, then "dip and swirl" the MAF sensor

into it a few times... shake and let dry for a few minutes...

after re-installing, unplug battery for a few minutes to reset computer... MAKE SURE YOU HAVE RADIO CODE...

2. While the sensor is drying off.... remove air intake tube and give throttle body a good cleaning with some

carburator cleaner or thottle cleaner... watch out for over spay into eyes!

3. New Air Filter??

4. Check tension on throttle cable... cables can stretch over time... a little trick to increase rpm idle and throttle

response is to add a "zip tie" to the very end of the cable where the "hammer anchor" at the very end of the cable slides into

throttle control hook.. ... its like adding a little spacer in there to take out some slack.. just enough to take

out some tension.... not too much or your idle will be too high... I had to play around with it a bit to get it just right..

... think of it this way too... if cables are stretched enough then full pedal fully pressed is only opening throttle body 90% versus 100%

see here for a little more insight

http://www.renntech.org/forums/index.php?showtopic=4446

5.. Fuel or gasoline treatment to clean injectors...

6. New spark plugs

7. better fuel.... are you using cheap gas, low octane??

those a few things I would try first... if all else fails I am sure the dealer would not mind

taking your money ;^(

Hope these work instead of dealer... all the best.

Bill

Hi qikgbn,

Thanks for your best wishes and your very much appreciated advice. I cannot wait for my engine to arrive.

1)I will check tehe RMS, hopefully it is still the old one and I can replace it easily.

2)I have replaced my coollant bottle recently. (2nd time) It seems that they only last about 100k km's. My car has done 208k km's now.

3)My clutch is my biggest worry at this stage. I will look into the cost of the 987 clutch, in SA it is very expensive. I'm not really into the drag racing thing, just do not want these kids in their street racers to out accelerate me.... lol.

4)I will make sure that tmy motor mounts are in tip top condition. I do not want the engine to fall out the back.

5) I will install a hi flow intake.

6) I am going to first run the car with the normal radiators. If additional cooling is required I will install the 996 bumper with the extra radiator.

7) New radiator hoses it will be.

8) No racing for me. I will check into the cost of the baffles, and if not to expensive I will install baffles.

9) Porsche South Africa have aggreed to do all the programing of the DME that is coming with the engine, they have access to the required security codes for the security system.

10) I will also look into the air/oil seperator cost and again if not to expensive I will replace it.

Thank you very much for your interst and suggestions. I appreciate it very much.

Regards

Pieter

Gentlemen and Ladies.

Have I forgotten anything?

Regards

Pieter

1997 2.5l Boxster (soon to be 3.4l)

5 speed Manual

Guards Red

Hey Pieter,

Congratulations on your conversion to 3.4. A few things I would recommend while you have the motor out...

Best of luck.... If done properly you will be very happy!

Bill

Hi Pieter,

No problem. I know how stressful and exciting an engine swap can be. Stressful because you want everything to go smoothly, run properly, and last long.

Depending on the motor, programming, and your bolt on additions like exhaust and intake a 3.4 motor can make anywhere from

280 horsepower to 325 hp. So getting the right combination of parts together can make a big difference.

I am not sure if you have access to discount parts like Sunset Imports (800) 346-0182 that may or may not ship overseas, not sure.

but off the top of my head these are some prices I paid approximately... don't quote me though ;^)

best thing to do is call Sunset. They are nice guys over there.

--As far as RMS. The seal part is only around $10-15 dollars. So it is not expensive, but needs to be installed properly

and with care. It will help you sleep better knowing the seal has been updated.

--The clutch disc and pressure plate were around $300-350 dollars from Sunset

ask the parts guy to cross reference the part number for the 986 2.5 5 speed versus

the 987 boxster S.... Maybe the disc part numbers and bolt patterns are the same, ...

I changed mine 3 years ago, so the details are a bit hazey. I have had no problems

with over 20,000 miles and I drive aggressively.

--throw out bearing may be included in clutch kit and the pilot bearing was not that expensive... maybe $20

--the oil baffle was around $30 but needs some Porsche sillicon gasket stuff to reseal the oil case.

--AOS was around $90-100

-- dual mass Flywheel... expensive... like $600-700

-- one more note on the air intake... The hi flow air intake is part of the solution.

The "size" of your MAF housing makes a bigger difference because it relates

a voltage signal to your 996 ecu. Based on the voltage signal the 996 ecu

applies certain fuel maps. It is ok to use the stock boxster maf housing, but

just be aware that using the smaller housing sends a "higher" signal to

the ecu because air has to pass faster through it than a 3.5 inch housing.

This higher signal will change your fuel maps and run rich.

There are easy solutions to this as you may have read already in the post

I gave you earlier. It could be as simple as applying a small resistor to

the maf signal wire. But it makes a big difference in performance.

all the best. keep us updated on your success...

B

Gentlemen and Ladies.

My 3.4l engine is on it's way from the USA to South Africa for my MY97 Boxster!!!!

A few questions please?

1) Best clutch to use?

2) Any gaskets that I must pre-order so that the swap can be done without to much standing time?

Let me see:

1)I have somebody with PS2 to programme my DME. (spare DME comes with engine with programming codes)

2)Have spare harness so that I can get the pin for the extra wire to the resonnance valve.

3)Have 1 week leave to do the swap.

4)Have clean overall.

Have I forgotten anything?

Regards

Pieter

1997 2.5l Boxster (soon to be 3.4l)

5 speed Manual

Guards Red

Hey Pieter,

Congratulations on your conversion to 3.4. A few things I would recommend while you have the motor out...

1. Change the RMS (rear main seal) to the latest offered by porsche for the 3.4...

Porsche has upgraded and made this part better several times now. Get the latest and greatest.

2. Depending on how old your plastic Coolant resevoir container is. I would replace it.

early boxsters and 996's had problems with these cracking when they get old. I had replaced

mine once with the 2.5 motor and then replaced it again just to be safe when I put in the 3.4

since they run a little bit hotter.

3. Change out your flywheel as well. depending on your mileage it may be a good idea.

I replaced my clutch with the 987 boxster part number and have had no problems getting

325 hp to the ground. But unless you drag race all the time, then you will want something

stronger. get a new pilot and throw out bearing. Flush your clutch fluids..

4. change your motor mounts if they look tired. you will be dealing with a lot more torque under hard accelleration

and engine breaking.

5. Very IMPORTANT. Install a hi flow intake if you want proper performance. The boxster airbox is

too small... You also must have a MAF housing tube that is 3.5 inches like the stock 996

or if you use the boxster 3 inch maf housing then you will need to modify or "callibrate" your

voltage signal for your 996 ECU to apply the proper fuel maps or else it will run very rich.....see this thread

it explains a lot on proper MAF signal: 20-30 hp difference.

http://www.renntech.org/forums/index.php?s...mp;#entry125122

6. If you live in a very hot environment then a center radiator may be a good idea, but then you would

need an opening in your front bumper for air flow as well. this is optional...

7. replace any coolant hoses that look dried out or brittle.

8. If you plan on tracking the car there is an "oil baffle" made for the 2001 and new engines.

This keeps oil from sloshing around so much during hard cornering and causing oil starvation..

If you have a 1999 3.4 engine then it may not have this baffle in it..

9. make sure to get your key reprogrammed as well to work with the 996 ecu and alarm system.

10. Think about also replacing the Air Oil separator.. much easier to do while engine is out and these

do go bad depending on mileage.

Best of luck.... If done properly you will be very happy!

Bill

Spring is almost here....Put some new 19" on the BOX, and washed her up....its still a bit chilly, but warmer days are near! :D

Wheels look Great! could you tell us what the width is on those 19's and did you need spacers? How does the ride quality feel?

Great choice, they really look great.

Bill

I just got my car back after the new 3.6 engine conversion has been completed. The car is awesome except I'm not getting any sound to my speakers. The battery was obviously disconnected during the engine change and I'm wondering if that has anything to do with it.

I have a Kenwood DDX7015 CD/DVD/NAVI with a large amp in the trunk. I did not install this system (previous owner) so I know nothing about it.

I'm pretty good with an engine but not audio equipment. The company that did my conversion has no idea why there is no sound to the speakers. They will pay for any repairs or diagnosis to get it fixed.

Just thought I would get some insight from the forum

Any help would be greatly appreciated

Thanks !!

Phillipj

:D

Usually the amp has a seperate power lead to the battery. If the battey cable was disconnected, I would assume that this cable may be hanging by itself. Pull the shroud and see if you have a power cable to the amp off! Power amps turn on and off by use of a sense singnal

Hence the direct connection to the battery.

Thanks Kevin! I'll look at it tomorrow. One question, How is the cable from the amp usually attatched to the battery?

Thanks

Hey Phillip,

So how is it?? What did you notice first about the new motor. is it night and day?? details, details... ;^)

what else did you have done, any mods?

Bill,

Thanks again for the excellent response I think i might be sold on the resistor solution combined with the AEM meter since all the other options seem to be much less cost effective for possibly little advantage. Do you know if anyone has a write up on it ? Again thank you for your help.

What part exactly were you looking for a write up on? If it's AEM meter ?'s or AFC Select MAF controller ?'s

then I can share my experience... If it has to do with resistors, rheostats, or variable pots... then

members Todd or porsche 1999 are the goto guru's...

Bill,

Yes I have read that thread. I read it shortly after Todd told me about the MAF housing and so i did a search on the subject and came across your conversation. I like the air/fuel meter idea but i really want to avoid the resistor method if possible because I would like to get in the amount of air that the engine was designed to receive. I will definitely look onto that air/fuel meter. What are the advantages over the one you mentioned vs others? Thanks for your help everyone.

Todd mentioned he was not convinced the boxster "airbox intake" could supply enough air.

I agree, about the stock "airbox", but I'm on the fence about the

3 inch piping going to throttle body if a cold air "cone" style intake and a

straight 3 inch pipe all the way to the throttlbody replace the constrictive airbox..

I definitely saw an increase in performance on the dyno with the cold air intake

and new plumbing..so the 3.4 needs to breathe better for sure..

With the less restrive cone filters It may be getting the air it needs,

but it just has to travel faster through 3 inches versus 3.5.

What surprised me is that I've looked at some RUF photos of their

3400s air intake tube that attaches to the throttle body and it is the same as stock boxster..

but RuF definitely modifies the "airbox" for higher flow.

There are some cheaper AFR gauges costing around $50 and they splice into the wires

of your existing "narrow band" Oxygen sensors. they read a voltage and give you a read out whether

"lean or rich" , but not a very accurate air fuel ratio Number...

I am sure they work "ok" if you want to know if you are basically rich or lean ...

but if you wanted to know exactly how to dial in 12.5 or a 13 AFR it would be difficult with those gauges.

My dyno tuner said the only way to get a very accurate reading is with a "wideband" sensor.

These guages which cost around $200 come with their own oxygen sensors and

are also able to plug into other types of software for further tuning. This allows pro logging data

at the dyno so that you can get a better reading pre-cat than a "sniffer" stuck in the exhaust

will give you.

On a cosmetic side I chose the AEM also because it came with different color gauge faces and bezels so that

it can match perfectly with my silver face gauges or swap for black if you have black faced gauges/bezels..

see quick youtube of overviews ..here are 2 vids to look at..

http://www.youtube.com/watch?v=ivOtfoY8P2Y...feature=related

If you can find a proper size Maf housing and intake plumbing then the AFR gauge may not be completely

necessary because you still will not be able to "adjust or modify" your signal in any way...

You could have it dyno tested once for about $80 to make sure you are good to go with your AFR

and never worry about it again.

AFR gauges are great for those who have a bit more tweaking to do

and have a way of "tuning" so they can dial it in. so if you added a "variable pot resistor", then you

could tune or dial in your AFR... that's when the gauge would be very useful...

well, hope this helps... all the best

Bill

Hello everyone, I have a Boxster with a MY 99 996 3.4 engine conversion. Any way Todd helped me discover why my car has always run rich, which was due to the use of the stock Boxster air intake system that uses a 3 inch diameter MAF housing vs the 3.5 inch used for the 996. Anyhow, I have looked at some possible solutions but am open to any suggestions. Does anyone know what the diameter of the Cayman S and 987 Mass Air Flow housing is? I think this might be my best option. Thanks for your help. :renntech:

Hey Monkey...

If you talked to Todd then you probably already came across this thread:

http://www.renntech.org/forums/index.php?s...=21472&st=0

Todd, 1999, and I talked extensively about this exact issue.

similar results with a few different ways of getting there.

from the cheap to a bit more expensive...

It depends on how much flexibilty you want in tuning.

I don't know if you are like me, but I wanted to see the results of

my tuning/changes. I spent many hours and many dyno runs getting my car dialed in.

The one thing that gives me instant feedback without having to go to dyno

anymore is the AEM wideband Air fuel ratio gauge: $200 on ebay...

website if you wanna see what looks like:

http://www.aempower.com/ViewCategory.aspx?CategoryID=67

This requires adding a "bung" and tapping sensor into exhaust.

$40-50 bucks for muffler shop to install bung. Then just screw in sensor

and easily run wire into car and plug in gauge. Having and Knowing your exact AFR

will save you a lot of dyno tuning and money later if you do additional

tweaks or add ons.

Then it is up to you how to handle the maf signal correction... either increase

the size of the maf housing to equal that of the 996, or "calibrate"

the voltage signal from the maf to the ecu using a type of resistor ....

if you are running rich, then the voltage signal from the maf is too high.

best of luck.... Once it is corrected you will feel a very nice difference

all around. Like a new car ;^)

Bill

Before you go with the vacuum switch, what is your MAF signal right now at idle. It should be around 15.5 kg/h. If not put around a 560 ohm resistor inline on wire #5. Check the idle MAF signal again. Add or subtract resistance as required to get it to 15.5. Once completed, I suspect your WOT A/F ratio will be pretty close to what you are looking for. The variable MAF control is what I use because I also have a variable intake system which increases intake air at higher rpms. In your case, since all your air is going through a constant sized intake, a single resistor will work. If your A/F ratio is a little high or low at WOT, either increase the resistor size slightly to make it more lean or decrease it to make it richer.

If, for some reason, your ECU was tuned incorrectly, the variable MAF control may be the answer. Using the vacuum switch as I described will provide a seemless, instant transision between signals. Set the switch to be off with ANY vacuum and on without.

No way.... so since I am running a straight 3 inch Maf housing and intake pipe all the way to the throttle body a single resistor or rheostat would

have done the trick??

so are you saying all I had to do was add a little resistor inline on my maf signal to the ecu similar to like this photo??

http://www.houseofrage.com/tundra/rrtun33.jpg

Or run a single rheostat inline before the ecu and just dial the rheostat down to get the desired 15.5 kg/h reading at idle??

That makes a lot of sense since the smaller 3 inch maf housing piping has globally offset the the voltage. just turning down

the voltage globally to the levels that a 3.5 inch housing would produce would be enough to trick the ecu. ****, your good.

wow, should have had this dialogue a week ago. I would have loved to try this out, but at this point I have already committed

to, installed and dialed in the AFC-SELECT unit... I am still very pleased with the results I have and the fine tuning flexibility the AFC-select +/- 50%

correction it gives you makes it a really fine tuning gadget. Plus it has a lot of cool flashing lights... haha...

One last question... so is an AFR of 13 flat across the board the most ideal setting or is 12-12.5 a better bet???

Thanks so much for your input. I learned a lot! I am sure this dialogue will help a lot of members.

Bill

The easiest and most effective way is to simply get an adjustable vacuum switch similar to the one shown in the link below. The MAF signal #5 wire would be cut with the DME side of the wire going to the common on the switch and the MAF side of the cut wire to BOTH switchable leads on the switch. The switch is activated by vacuum, switching from one lead to the other depending on whether vacuum is present or not. The default lead (vacuum present) would be connected to the MAF side of the cut wire without resistor and the other lead would be connected to the MAF side of the wire with a resistor the size which will give you the A/F ratio you want at WOT. You could also put a rheostat inline to make it easy to test different settings

Using the above method, you maintain the current tubing configuration of the intake and it allows an easy way for fine tuning in a matter of seconds.

http://images.google.com/imgres?imgurl=htt...l%3Den%26sa%3DN

hey 1999....

very clever! So I noticed that on that particular switch you can "preset" a vacuum pressure with a little screw. Is there a certain psi needed before

the switch kicks in or do you just have it switch at the slightest vacuum change? I would assume you would figure out the vacuum pressure at a certain throttle position so that it switches close to wot???

I figure there are a lot of different resistor sizes to try out and picking the right one sounds like a lot of trial and error... The rheostat sounds like the way to go and you can just turn the knob down to dial lower the maf signal......aaaahaaaa... very interesting. Gotta know what rheostat resister range to chose though... , but what if you need a "stronger" signal because you are running too lean? hmmm

last question... since it is an "on/off" switch method based on vacuum there is not a lot of fine tuning involved, Kind of a one adjustment fixes all and then just leave it....... so how is driveability? can you feel it switching so quickly between the 2 maf signals?

Thanks for the info, that was very eye opening...very cool.

Nice job, but it would be alot easier to simply make your MAF have a variable signal. Maf would be calibrated one way in closed loop which would allow the O2 sensors to properly managed the a/f and then would switch to the another calibration in open loop. You then have a fully adjustable MAF signal and full control of your a/f ratio in a matter of seconds.

hey 1999-911 and Todd, I have read a lot of your posts on conversions and Thanks for all your input and knowledge...you guys rock!

I actually got my hands on a stock 996 air box with the intention of cutting out the MAF housing to use with my

cold air intake... well, as you already know... not so easy. I then tried to find some 3.5 inch tubing and create my own

MAF housing to mimic this as well, but gave up. The idea of fine tuning won me over in the end.

You both have great ideas and options with the similar idea of controlling the MAF signal, but how exactly do you rig it to be able to do that?

How do you control when it switches from "closed" to "open" loop calibration? Is it a throttle position or rpm?? Is it a unit you buy and splice

into the maf signal wire at the ecu? what's it cost?

The AFC-select works a bit like that. 4 wires are connected at the ecu to monitor Throttle position, power, MAF signal, knock sensor. The maf signal wire

is the only wire altered so that the signal is sent to the AFC-select unit and then a "new corrected signal wire" is sent back into 996 ecu.

What I was impressed with on AFC-select is the ability to designate exactly which rpms to correct voltage % on and at what throttle position I wanted to adjust the signal on. For example: If on the dyno my MAF signal at 70% throttle position (tp) is already giving a rich afr of 10. Below 70% tp the afr is ok.

So in this scenario by throttle position 70% I wanted the the voltage corrected by -20%. I can create the parameters for the

throttle position like this: at 20% tp = 0% voltage correction...correction would ramp up smoothly so that by 70% throttle position and above = 100% preset voltage correction is reached. (voltage correction being preset at -20%) This allows us to have a nice smooth linear correction on MAF signal output.

then we fine tuned every few hundred rpms to smooth out any bumps or dips in the AFR readings.. After all was said and done we made about 15 runs on the dyno as we adjusted the signal correction little by little to make sure of never running too lean.

Is there a way to do this type of callibration with a simple resistor to alter the MAF signal?

I am all for any solutions or ideas to help. Especially since a lot of us have gone down the bolt on mods and conversion routes only

to be disappointed when things are not running properly and as expected. After a couple hundred miles this weekend I am very pleased. Now I have to just

keep my fingers off from tinkering with the computer to get that last little .01% correction ;) I also find myself watching my afr reading like crazy whenever I accelerate at wot. It has been great though and holds 12.0 afr pretty solid. Sometimes too many gauges are a distraction! :o

What AFR's do you find to be ideal and safe??

Thanks again for your input. it is greatly appreciated.

Bill

I realize these posts were awhile ago, but I know there are many of us still dealing with this problem of our MAF sensor

causing rich or lean AFR's when we start adding bolt ons. I have had a major break through and wanted to share

the solution I came upon.

I have a 98 boxster with a 3.4 liter conversion. I have had it over a year this way and have been driving it using very

rich AFR's for most of the time. My AFR's have been reading in the 10's for quite awhile. Even this way the car was making

decent power, about 310 at the crank, but with all of my modifications I should have been closer to 320-330.

ECU Tuning has been a break through, but not how you think. I originally had "powerchip group" reprogram my ecu rom, but after 3 different programs and 3 100 mile round trips to their facility I was still running very rich. I then contacted "Steve", owner of SR Motorsports in Gardena (310-516-1003) for some dyno tuning. He has some amazing experience with tuning import cars and was in the research and development for APEX products for 5 years. I was running very rich for awhile and my Air fuel ratio readings were around 10 under wide open throttle on the dyno. The basic idea we discovered is that the MAF housing diameter for the stock 996 is 3.5 inches. For the Boxster it is 3 inches. When the 3.4 liter motor is drawing in air it is pulling air in "faster" through the smaller boxster 3 inch MAF instead of the stock 996 3.5 inch housing it was oringinally programmed for. This "faster/higher" reading sends a voltage reading to the996 ecu that calls for more fuel and thus richens everything at wide open. The opposite can happen if your MAF housing gets too big.

We wanted to be able to fine tune as needed so Steve recommended the "APEX AFC-SELECT" for german cars.

http://www.apexi-usa.com/product_electroni...5&pageNum=1

Hard to find these days, but they are out there. I also installed an AEM wideband Air fuel ratio gauge to monitor AFR's from within my car. The APEX AFC-Select allows us to control the voltage reading of the MAF at any designated rpm before it gets to the 996 ecu. By doing so the 996 ecu takes the new voltage reading and adjusts the fuel injectors as required. Thus we were able to fine tune my AFR to read a conservative 12 all across the board. From this tuning alone I gained 20-30 lbs of torque and horsepower across the mid rev range from 3500-7000 rpm. I was stunned and amazed at the difference! The whole process of installation and tuning took about 3 hours. Now I have a system that I can fine tune to my unique modifications. I would highly recommend this procedure over any "ecu rom tuning" in a heart beat because everyone's car mods are different. This eliminates wondering if your "reprogrammed chip" needs to be adjusted if you ever ad anymore bolt ons.

Steve's knowledge of the product and ease of use was paramount to making it happen so smoothly..Now granted this is not adjusting timing and other parameters that rom chips do, but for most bolt on mods that deal with faster air flow this is a great solution.

We wanted to start out conservative and tuned the air fuel ratio to hold 12 across the entire rev range at wide open throttle. We will later be raising it to an AFR of 13 which should result in a gain of another 10-15 hp and tq. For this test we will keep it conservative and safe at 12 for a few 100 miles to make sure no check engine lights or problems show up..

My before and after dynojet peak dyno readings at the wheels were as follows:

base: 255hp @ 6300 and 215tq @ 4600 (wheels) X 1.2 = 306 hp and 258 tq at crank

AFR=12 flat :270hp @ 6300 and 235tq @ 4600 (wheels) X 1.2 = 325 hp and 282 tq at crank

compare this with a bone stock 300 hp 2001 996 3.4 dynojet:

251hp and 213tq X 1.2 = 300hp and 256tq at crank

AFR=13 flat

Car has now been dyno'd with close to 325 hp at the crank and weighs only 2750 lbs.

Gtech Pro RR g-force meter performance run:

*adjusted

0-60 foot launch 1.9 sec

0-60 mph in 4.4 sec

0-100 mph in 10.5 sec

0-130 mph in 17.2 sec

0-150 mph in 27 sec

Quarter mile time 12.7 sec @ 110 mph.

I realize these posts were awhile ago, but I know there are many of us still dealing with this problem of our MAF sensor

causing rich or lean AFR's when we start adding bolt ons. I have had a major break through and wanted to share

the solution I came upon.

I have a 98 boxster with a 3.4 liter conversion. I have had it over a year this way and have been driving it using very

rich AFR's for most of the time. My AFR's have been reading in the 10's for quite awhile. Even this way the car was making

decent power, about 310 at the crank, but with all of my modifications I should have been closer to 320-330.

ECU Tuning has been a break through, but not how you think. I originally had "powerchip group" reprogram my ecu rom, but after 3 different programs and 3 100 mile round trips to their facility I was still running very rich. I then contacted "Steve", owner of SR Motorsports in Gardena (310-516-1003) for some dyno tuning. He has some amazing experience with tuning import cars and was in the research and development for APEX products for 5 years. I was running very rich for awhile and my Air fuel ratio readings were around 10 under wide open throttle on the dyno. The basic idea we discovered is that the MAF housing diameter for the stock 996 is 3.5 inches. For the Boxster it is 3 inches. When the 3.4 liter motor is drawing in air it is pulling air in "faster" through the smaller boxster 3 inch MAF instead of the stock 996 3.5 inch housing it was oringinally programmed for. This "faster/higher" reading sends a voltage reading to the996 ecu that calls for more fuel and thus richens everything at wide open. The opposite can happen if your MAF housing gets too big.

We wanted to be able to fine tune as needed so Steve recommended the "APEX AFC-SELECT" for german cars.

http://www.apexi-usa.com/product_electroni...5&pageNum=1

Hard to find these days, but they are out there. I also installed an AEM wideband Air fuel ratio gauge to monitor AFR's from within my car. The APEX AFC-Select allows us to control the voltage reading of the MAF at any designated rpm before it gets to the 996 ecu. By doing so the 996 ecu takes the new voltage reading and adjusts the fuel injectors as required. Thus we were able to fine tune my AFR to read a conservative 12 all across the board. From this tuning alone I gained 20-30 lbs of torque and horsepower across the mid rev range from 3500-7000 rpm. I was stunned and amazed at the difference! The whole process of installation and tuning took about 3 hours. Now I have a system that I can fine tune to my unique modifications. I would highly recommend this procedure over any "ecu rom tuning" in a heart beat because everyone's car mods are different. This eliminates wondering if your "reprogrammed chip" needs to be adjusted if you ever ad anymore bolt ons.

Steve's knowledge of the product and ease of use was paramount to making it happen so smoothly..Now granted this is not adjusting timing and other parameters that rom chips do, but for most bolt on mods that deal with faster air flow this is a great solution.

We wanted to start out conservative and tuned the air fuel ratio to hold 12 across the entire rev range at wide open throttle. We will later be raising it to an AFR of 13 which should result in a gain of another 10-15 hp and tq. For this test we will keep it conservative and safe at 12 for a few 100 miles to make sure no check engine lights or problems show up..

My before and after dynojet peak dyno readings at the wheels were as follows:

base: 255hp @ 6300 and 215tq @ 4600 (wheels) X 1.2 = 306 hp and 258 tq at crank

AFR=12 flat :270hp @ 6300 and 235tq @ 4600 (wheels) X 1.2 = 325 hp and 282 tq at crank

compare this with a bone stock 300 hp 2001 996 3.4 dynojet:

251hp and 213tq X 1.2 = 300hp and 256tq at crank

AFR=13 flat

Car has now been dyno'd with close to 325 hp at the crank and weighs only 2750 lbs.

Gtech Pro RR g-force meter performance run:

0-60 foot launch 1.9 sec

0-60 mph in 4.4 sec

0-100 mph in 10.4 sec

0-130 mph in 16.5 sec

0-150 mph in 26 sec

Quarter mile time 12.7 sec @ 110 mph.

The smoke was greyish in color, it smelled like combustion gases to me.

I was just suprised to see so much smoke after only sitting a couple of hours.

As for my location, I am in central Ca. (Clovis).

Many thanks for the responses guys! B)

Hey B

I had the exact same "phenom"... started with a weird smell for a few days after parking car in garage. Then

cloudy start ups, not too bad and would go away after driving. Then one day the cloudy start up was

filling up the garage with smoke, but still seemed to go away... As most of us are guessing right now..

early Air Oil Separator going bad... I caught on soon enough and had it changed right away... No more

smokey starts.

If you call and ask for the porsche part number you will see that

the last couple digits represent how many versions of that part they have changed or improved.

I think they are up to 05 or 06... meaning it's a part that has been changed or redesigned by porsche

5 or 6 times... I ordered the part from Sunset Porsche discount parts and then had the dealer do the labor.

I hear it is a pain to DIY....

best of luck... Bill

Thank you for your help Todd.

I spoke to the shop owner this morning and he did the right thing. He asked for the car back and said he would figure out what it takes to get it right.

I will keep you posted.

Hi and congrats on the 3.4 conversion.

I also have a 98 boxster 3.4. I also noticed a little rougher idle between the 2.5 and 3.4 motor, but it is nothing to worry about.

I have driven a few 3.4's and the stumble in idle seems common or normal. Just as long as the rpm's stay around

800-900 during idle.

I also created a small spacer at the very end of the throttle cable where it attaches to the throttle body

in order to take up some of the "slack" in the cable. It made a nice little difference in throttle response.

As far as ECU... When I purchased my 996 3.4 engine (used, 18,000 miles on engine) we also got the 996 computer

that came from the same car with that motor. Then added the "powerchip group" ecu upgrade.

Now that I think about it, we had to also use a new key "computer chip" inside the key that the 996 ecu would recognize.

same key blade, just different chip in head of key. I have had no problems or "check engine" lights since the conversion

and 10,000 miles.

3.4 loves to rev up to 7200 rpm's all day long. Obviously our boxster rpm gauge shows redline at 6600, but the motor should

pull even harder all the way to 7200 rpm.

I agree with an earlier response as well... while the car is idling

look inside the motor on the top at the intake manifold. There should be 2 "resonance" pipes connecting across

the left and right intake manifolds. (2.5 liter motor only has 1)

1 resonance pipe is part of throttle body plenum, the 2nd one behind it has a little valve actuator arm that you

should be able to see swing open when the rpms rev to over 3000 rpm. Rev the car slowly by twisting the

throttle body where the cable attaches and see if the valve actuates.

hi flow intake is a big plus. Especially when reving to 7200 rpm. 2.5 liter airbox is too small for those higer rpms.

I saw a 10-15 hp increase between 5500-7000 rpm just from adding a cone high flow intake and modified intake pipe.

I also modified the air pipe that goes to the throttle body. The stock 2.5 mid section has a lot of "crimps and restrictions" in it.

I basically got my hands on a extra pipe, cut off the ends and used the ends to connect to the throttle body and "MAF" sensor housing,

but cut out the middle and replaced it with a nice, smooth 3 inch diameter by 10 inch length section of pipe.

I then used rubber couplers and hose clamps to connect the new sections together. It worked out great. similar to this design.. http://www.rahul.net/dennisp/boxster/boxst...ds-intake.shtml

Dyno's... need to be taken with a grain of salt. I have seen 10-15 hp difference between 2 different dynojet locations

even though temp and humidity were similar.. go figure. I would not be surprised if you are seeing 250-275

hp readings depending on dyno's. I purchased a "Gtech Pro RR" that is an in car "accelerometer" and measures

g-force in order to give you 1/4 mile times and 0-60 mph times etc. Because that's what it comes down to, acceleration.

Currently my 3.4 liter boxster measured these times on the Gtech Pro... with a good launch ofcourse...

0-60 ft 1.9 sec

0-60 mph 4.4 sec

0-100 mph 10.6 sec

0-130 mph 17.3 sec

quater mile 12.8@110 mph.

based on a online dyno calculator:

http://www.corral.net/tech/brakehp.html

I entered these values for my car

3000 lbs (2700 + driver+fluids) guess-tamate

trap speed 110 mph

elapsed time 12.8 seconds

=318 hp crank and 280 hp at wheels... cool... I can live with that.

This is what will drive you batty on dyno's...I have to admit I never really saw

280 hp at the wheels on any dynojet or dyno machine. Yet my acceleration times are

still pretty fast.

I really hope you get all the bugs ironed out and can really enjoy the ride.

I just drove through the mountains this weekend and I love my 3.4 boxster.

After my 3.4 conversion I made myself crazy trying to find 10-15 hp more because

of my dyno readings being lower than expected... After you get all the bugs out

you will get use to the additional power of the 3.4 all over again and then wish you could

somehow afford a 3.6 liter gt3 engine in a boxster... The need for speed never ends ;^)

best of luck.

Bill

Can you post your before and after dyno's? After reading both your impressions this is something that is getting more and more intriguing to me.

Thanks in advance,

Pete

Hey Pete,

Now that I have had the plenum on for a couple of months I am still really happy with how it "smoothed" out the power band.

Dyno's are taken with a grain of salt. I recently found a different dyno jet shop closer to my house and had a dyno done

a few days ago. There is a 10-15 hp power difference between the 2 dynojet shops.... Ofcourse you have to always consider

outside temperature, fuel quality and all the misc factors that go into dynoing any car. No two days will ever be exactly the same....

The best thing I can say about the IPD Plenum is that there is a definite increase between 5000-6500rpm. This is where

the power really smoothed out and stayed consistently higher than before the plenum was installed. I saw a 15-20 hp difference

between 5000-6000 rpm. It was mostly due to the fact that prior to the plenum there was a dip or flat spot in power just before the resonator valve opens and vcam switches. The Plenum really helped smooth out that flat spot for me and increased the power. So for me the plenum was worth it.

Outside of that rpm range the plenum increase for me is 5 maybe 10 horspower across the rest of the rpm range.

I did some stopwatch times. I know these are not super accurate to press the stopwatch while driving, but still good to see

a general idea of where the car is at performance wise.... 3.4 liter boxster.

0-60 mph = 4.4 sec.

0-100 mph = 10.8 sec.

0-130 mph = 19 sec.

0-150 mph = 29 sec.

Just replaced my stock plenum with the RSS plenum over the weekend. I have never really done a DIY on my car so I was a bit nervous.

Thanks to Chuck Jones advice (who sold me the plenum) the job was quite simple. If I did it again I could do it in half the time.

I have to say I'm quite pleased with the performance with the new plenum. The performance is most noticible between 4500 and 6500 rpm.

The car gets to 100 mph much quicker than before. I have no idea what the gains really are.

I'm going to do a run against my friend who has a 997s coupe that is chipped. I have run against him before so I will be able to gauge the difference.

If anyone is planning to do this mod themselves pm me and I can give them some tips to make the job even easier. Tools needed are minimal. The instructions that come with the plenum are okay but not detailed enough.

:cheers:

Phillipj

Thanks so much Phillip for your feedback and input on installation tips.

I installed the part last night and put about 60 miles on the car throughout the day.

It did take about 20-30 miles of me getting on and off the gas

for the ecu computer to pick up the new airflow change and WOW! What a great difference.

My seat of the pants told me that the power curve really smoothed out a lot, especially between 5000-7000 rpm.

The more I drove the stronger that pull got throughout the day.

I then took it to the dyno today as well and I am very pleased.

I saw a before and after change of 10 hp and 10 lbs of torque between 2000-5000 rpm.

Then wow... from between 5000-6000 I gained 20 hp because my power curve use to flatten

out right before the vario cam kicked in and now it just soars and keeps climbing through the old flat spot..

From 6000-7000 rpm the hp gap goes from 15 back to 10 hp up over the old curve...

I really am impressed With the difference. Especially the smoothed out curve and 20 extra hp @ 5400 rpm.

I wish it continued all the way through the rpm range, but I have to say I am a believer now.

I paid about the same price for the powerchip upgrade, but only gained about 10-13 hp. This has

to be one of the best and easiest upgrades yet. I am very happy with it and have seen and felt

the real world difference of this product.

Take care... just wanted to share my findings with you..

Billl

Have you tried Carnewal.com?

I finally got the kit from Carnewal after a 5 weeks wait. It seems the kit doesn't come with any bumstops and I'll take this opportunity to install new ones rather than re-use my existing ones.

Is there anything else that's not included in this kit but would be a good time to get new ones rather than re-use the existing parts from the stock suspension? I want to make sure everything's in place before the swap begins..

Thanks.

I ordered mine from Sunset Porsche and it took 3 weeks. It really must be luck of the draw with timing and parts being available in Germany.

Haven's seen any Tiptronic 3.4 upgrades.

Is 36% more HP really worth spending $16k for in a 8-10 year old car? All those old suspension parts and wires and hoses....

Or is buying a new one the better way to go?

Or even better a slightly used year old one?

Hey Mike,

I went through the same thought process... I guess you would have to think more about it if you did not already own a boxster....

Now I mentioned that the cost could be $12-16 based on what you wanted to add, replace, or upgrade. I have met some that

have had the work done for closer to $10k. $5000-6000 for motor and $5-6 k for labor...

I spent a little extra on having some of those "tired parts" replaced new flywheel, engine mounts, suspension bits etc...etc..

That way I can feel that I have a great car in good condition for the next 5 years....

Now, if I were thinking of purchasing a boxster for the first time... then that's a different story. I would definitely go

with the latest model I could afford and lean for the "S" model..... A 2002 Boxster S with an 3.6 conversian will net you

a 2855 lbs Porsche with 325-340 hp for about $40,000 ...... The 2007 3.4 Boxster S or Cayman will be in for a surprise

and You can get your wife a used Cayenne S with the money you saved.... that's kind of what I did :D

So my 1998 3.4 Boxster has the performance and a bit quicker than new Cayman S and Boxster S... Still looks like new too...

and is payed off! wooo hooo...

another note... I agree the 3.4 liter conversion is more "pure porsche" compared to supercharge or turbos...

hello, does any one know how much would it cost for labor and time to do the conversion from a "1998" 2.5 boxster to a "1999" 3.4 996 motor ,tiptronic trans. and if any one know of a good mechanic in losangeles?

thanks in advance

Ali :)

Hi Ali,

I just had this conversion done a few months ago in Los Angeles. I have owned my arctic silver 1998 2.5 liter Boxster for over 7 years now.

It is "the other woman" according to my lovely wife. Needless to say I love it and it is a hobby of mine

to work on it and change out interior parts as well as exterior with stuff with more updated parts or go fast goodies.

I currently have the 1999 tequipment aero kit on with 18 inch carrera lightweight wheels, 7 mm spacers and RoW M030

suspension upgrade from sunset Porsche as well as Gahh glass convertable top.

Misc hacks done for a bit of minor speed upgrades were:

--desnorkel air intake -- k&n air filter--power chip. I had the car dyno'd and it made a respectable 220 hp at crank.

BUT... as you know, this car can handle so much more power... and I always dreamed of Ruf's 3400 power and reliability.

So I went through a lot of research for a 3.4 conversion mechanic. I spoke with several shops and had several recommendations,

including Ruf technicians.. Well with 93,000 miles on the 2.5 liter, it was time to buy a Cayman or upgrade my motor...

There was something I love about my car and I could not part with it since I have made it my unique hobby.

I finally wanted to give it the power it deserves. Plus... at weighing in at 2755 pounds and potential 320 hp.... it was a no brainer for me.

First step:

I got the 2000 3.4 motor from a good friend "Todd", owner of Los Angeles Porsche Dismantler. (818)-Porsche

I was fortunate and we found one with only 18,000 miles on it. Todd was such a great resource of information and very professional,

but very busy as well, so patience is key. I also got a boxster S front center radiator as well as Carrera 996 front brake calipers with rotors

from Todd as well. He has hundreds of cars that have been totalled in crashes, but yet still have great parts left on them.

A porsche enthusiasts buffet table!

I later had the steel braided lines installed and system blead while motor was being installed..

The Carrera front brake calipers and rotors are same identical size that Boxter S uses...except painted black.

I highly recommend upgrading the front brakes this way. The added hp power justifies the need for stopping power.

Super easy installation... Hardest part was just bleeding the brake fluid.... and that is not that hard.

2nd step... Finding the right mechanic with a solid reputation and know how for 3.4 conversions.

I finally ended up contacting Claudio Szyszkowski's shop... Foreign Sport Technicians in Santa Monica.

310-394-0369.

I First read an article about Claudio in "Excellence Porsche Mag" June 2000 edition. He is Gemballa's

go to man for Los Angeles. In the article he performed one of his first 3.4 conversions on a black 1999

boxster owned by Dale Launer. The article mentioned how reliable and "factory installed" the final product

looked and drove. So I was already impressed with Claudio. Now, almost 7 years after the article was

written, Todd from Porsche dismantler recommended Claudio as one of the mechanics he trusted

and that I should contact and see about doing the install.

I was pleasantly surprised and happy because I was really familiar with the article and Claudio's name.

So I went to Claudio's shop and what do ya know, but the black 1999 boxster that Claudio did his first

3.4 conversion was there at his shop having maintenance and oil changed. He gave me a ride in it and

I was hooked. It had lots of power and torque. The torque is not like a big V8 motor... but impressive

none the less. Where this motor loves to be is above 3000 rpm. It just hauls *** and screams

all the way to 7200 rpm.

Claudio admitted that this car was like his prototype and he has learned a lot about the conversion

process and what works best since then. He mentioned my car would likely be a bit stronger and faster.

Mostly due to updated headers, powerchip upgrade, and I used a 2004 boxter S exhaust where dale still had the original 2.5

liter muffler.

So the installation takes 3-4 weeks to be safe and take the right amount of care, preparation, and shake down.

Claudio was very professional and allowed me to stop by any time to get quick updates or take photos.

He makes fun of me now at how many photos I took. He called me when ever he found a part that needed

replacing or just looked "tired" and was ready for replacement.

Long story short.... The installation went great. I have had the car dyno'd again and it is making

about 310-320 hp at the crank and 270 lbs of torque. Dyno's are a weird science...It is my daily driver and feels

like I bought it from the factory with this motor in it.

I recently got a Gtech Pro RR Gforce meter that measures time to speed and cornering performance

here are my results:

60 foot time for launch on start.. 1.9 sec

0-60 mph 4.4 seconds.

0-100 mph 10.6 seconds...

0-130 mph 17.3 seconds

1/4 mile 12.8@110 mph.

I love it!

as far as price...??? really depends... but motor + install..... expect to pay $10-12k depending on parts, upgrades, and

other stuff...