KevinMac

Kevin, not sure your weight is correct for the Al block LS.

Ahh - you ar right the LS6 fully dressed is 497lbs, still heavier then the porsche engine, not to mention that it is not a flat configuration, meaning the center of gravity on the rear will be changed.

The flat six naturally aspirated comes in at around 418lbs with all accesories, 350Ci chevy with all accessories will come in close to 600lbs. Nothing like hanging more weight at the rear of a 996 or 997 not to speak of a higher profie engine! Not so sure you are correct on the Porsche 4 being 50 lighter then a 350 since the Porsche 4.7 V8 came in at 574lbs.

I am not saying I don't believe you.

Do you have a picture of it?

I will take a pic of the old knob & boot assembly and try and post it. Need to get up in my attic to get to the stuff I pulled off recently.

Thanks!

I have taken more than 50 of these off and I have yet to seen anything different than what I described.

Well then I must be crazy! Because i just did mine 2 months ago and the standard one had a set screw in the upper front! Say what you will!

Have a 2k C4 Cab that recently has been acting up. When you set the climate contol to auto and set the temp at..say70 F it seems to heat the cabin well past this temp. I have never had a problem with this in the past and have thought it was one of the best climate control units out there.

Any suggestions?

Thanks

The cabin temp sensor may be at fault.

Loren - I had the standard knob shipped with the car, clear black top, no trim ring etc. It had a set screw when I updated it to the aluminum/leather look, porsche crest, and trim ring! So I don't think it's the standad vs, the upgrade.

Yeah nitrogen is the latest cash in the pocket technology! There is some merit maybe when you race. Street use just more money in the dealers pocket! I hardly ever loose air pressure with compressed air.

I think it depnds on the year of the car on how to remove the shift knob. My 2000 C2 definitly has the setscrew in the upper front portion. On those that don't it seems a twist and pull releases it.

I am also at the understanding to use the Porsche short shifter and not aftermarket if ther is a chance you want to convert back. From what I have read you have to remove some bushings to install the aftermarket, and this destroys all the chances to change back.

I am in need of replacing my rear tires but upon reviewing the OEM specs I noticed that the front and rear have different tire wall sizes (i.e. Bridgestone Pontenza S-02A (Rear) 285/30 ZR18 (Front) 225/40 ZR18). The issue here is the 30 vs 40. Does anyone know why the front tires are bigger (40) than the rear (30)? Must I replace the rear with 30's or can I replace them with the same size (40) as the front?

Anyone know what Porsche was thinking about these two different sizes?

contact

BT,

Short answer is the larger rear tires ( lower profile) are to provide a larger patch ( traction) in the rear to compensate for the heavier weight distribution being in the rear of a rear engine porsche. The rolling diameter of the front and rear tires are the same.

Demosan

Sorry, but the "rolling diameter" is NOT the same. The diameter of the rear's are about 1/2 inch shorter. Check your own car using a level and measure to the pavement from the top of the tire. With the same diameter rims, which is OEM, it stands to be logical that the front's with a "/40" vs "/30" wall height would higher. I am not interesed in changing the rims since I do not intend to change tire width, but am wondering why the front's would be designed to us a higher wall, hence larger diameter?

BT,

You are correct that there may be a slight difference in "rolling diameter" in some of the standard factory fitments of tires, although the difference is not as significant as you think as the sidewall height is theortically calculated by the product of width and aspect ratio. For example, for my C4S, the standard tires are 295 x30 rears and 225 x40 fronts (18's both axles). The sidewall height of the fronts would be calculated as 225x.40 or 90mm. Rears sidewall height would be 295 x 30 or 88.5mm. SO you are correct there is a difference of 1.5mm, which is within the guidelines of being with 1-2% of theortical to ensure the AWD performance of the drivetrain is not compromised. I am not trying to sell myself as a tire fitment expert here as I had some of the same questions when I replaced the tires recently on my C4S. If you go to the tirerack.com website, there are several articles dealing with Pcar fitement issues that you may find helpful.

Regards, demosan :cheers:

Ok, thanks. You guys are great input. I appreciate the help.

Going with OEM specs.

Here is a great calculator to see tire specs;

http://www.miata.net/garage/tirecalc.html

You guys think this would sound good in my C4?

http://cgi.ebay.com/Custom-Porsche-996-Fib...sspagenameZWDVW

Pretty interesting. Like to see it in person.

Your cooling system is up front, coolant lines and radiators! Check your coolant level!

The axle bearing on the trans side may be worn out, thus making the seal wear. Rumbling noise can be indicitive of large bearing play due to wear.

Think the major difference is tread, more aggressive tread to use on snow and slush, than summer tires that utulize tread to evacuate water and more road surface area. Compounds in summer tires allow the tire to run at higher temps, winter compunds are geared towards lower temps.

If you go with 19 inch wheels, you will have to go to a smaller sidewall tire to maintain the same diameter as the 18" combination. One thing to keep in mind the smaller sidewall will allow you better handling, harsher ride, and if you get a flat the exposure of ruining the rim is greater. Also, the larger the wheel size the more expensive the tire will be.

The reason alternators are better then generators is the low rpm output, and it has little to do with the gearing per say. It's due to the fact that gen put out DC and alternaors put out AC converted to DC by the reg. Ac is more stable easier to regulate, and output of the AC is greater then that of a DC generator at a given rpm. Generators rely on permanent magnets to generate the output, alternators rely on a voltage source for field excitation.

Anyway back to the subject at hand - A battery in good condition and fully charged should have an output of about 12.4 volts at rest.

The reasons are exactly as I posted earlier.

The alternator gives better output at lower engine speed because

the alternator can spin faster without blowing up physically, than

could a generator, due to the lack of the segmented commutator,

and thus is geared higher. This is THE primary reason for their

use. (and, today, they are loads cheaper)

They became feasible for general use when silicon rectifier diodes

got cheap enough in the early to mid '60s.

A generator may use permanent magnets to bootstrap the system

but there is a still a field winding, as that is how the regulator controls

the output. Same as in an alternator.

For the people who don't want to believe alternator output is not as

high at lower RPM, see this output graphs about halfway down this page:

http://www.delcoremy.com/Alt24SI.aspx

(note though, the graph shows alternator RPM, not engine RPM,

you'll have to correct it for the gear ratio in your particular application.

The alternators discussed on that page have a max speed of 12,000

RPM. So, if hooked, say, to a 911 with a 7000 RPM redline, it might

be geared about 0.6:1. So at 2000 RPM alternator speed on the graph

the engine would be spinning 1200.)

Bill

wrjet - so why are you quoting me????????? if you read my input i am not disagreeing! BTW my input is fact!

The reason alternators are better then generators is the low rpm output, and it has little to do with the gearing per say. It's due to the fact that gen put out DC and alternaors put out AC converted to DC by the reg. Ac is more stable easier to regulate, and output of the AC is greater then that of a DC generator at a given rpm. Generators rely on permanent magnets to generate the output, alternators rely on a voltage source for field excitation.

Anyway back to the subject at hand - A battery in good condition and fully charged should have an output of about 12.4 volts at rest.

You can buy those plate hole fillers on line I did.

Heres the link,

http://eagleday.stores.yahoo.net/exteriortrim3.html

Keep in mind the larger the sidewall the worse the handling. So when you go big you better go lower number on the profile. So if you currently have a 40 profile going larger you may have to go to a 30 or smaller.

As long as the smell you are describing is not a hot coolant smell. If so you may want to check your coolant level.

Lets just say if a bearing is worn or damaged your oil pressure will be low.

Your wasting your $16.40, because a horn does not activate itself, either there is current running thru it or not. It in itself will not cause your problem. Your horn is triggered else where. You need the schematics to back thru it. Sorry no easy answwer.

Think you have to look beyond the horn, since something in the alarm circuit is passing current. Get hold of the schematic and you will see there are multiple paths that interface with the horn.

What would it take to install this unit if the car presently does not have one?

Hey, at least he fessed up. How many times do things like this happen and no one takes responsibility!

When using the correct tool, the normal motion of releasing the headlight usuaully cams the light forward some. So if the HL assembly is not caming forward, i think you have the wrong area.