Jump to content

Server Lease Renewal/Software Licenses

Our yearly server lease, software licenses, as well as hardware operating costs, WERE due Dec 4th, 2022. Our current donations have fallen far short of the funds we need to renew. Please remember the RennTech.org community is Member supported so please consider a donation to help...  THANK YOU!

Welcome to RennTech.org Community, Guest

There are many great features available to you once you register at RennTech.org
You are free to view posts here, but you must log in to reply to existing posts, or to start your own new topic. Like most online communities, there are costs involved to maintain a site like this - so we encourage our members to donate. All donations go to the costs operating and maintaining this site. We prefer that guests take part in our community and we offer a lot in return to those willing to join our corner of the Porsche world. This site is 99 percent member supported (less than 1 percent comes from advertising) - so please consider an annual donation to keep this site running.

Here are some of the features available - once you register at RennTech.org

  • View Classified Ads
  • DIY Tutorials
  • Porsche TSB Listings (limited)
  • VIN Decoder
  • Special Offers
  • OBD II P-Codes
  • Paint Codes
  • Registry
  • Videos System
  • View Reviews
  • and get rid of this welcome message

It takes just a few minutes to register, and it's FREE

Contributing Members also get these additional benefits:
(you become a Contributing Member by donating money to the operation of this site)

  • No ads - advertisements are removed
  • Access the Contributors Only Forum
  • Contributing Members Only Downloads
  • Send attachments with PMs
  • All image/file storage limits are substantially increased for all Contributing Members
  • Option Codes Lookup
  • VIN Option Lookups (limited)

Time to do a new swap

Recommended Posts

I have helped a number of people with their 3.4 swaps so I decided they were getting too common. Also anyone can buy a boxster with a 3.4 from the dealer now, so time to try something new :P .

Hmm wonder what is in the box???


Looks like a 2005 3.6L engine.


Should be fun.


Link to comment
Share on other sites

  • Replies 53
  • Created
  • Last Reply

Top Posters In This Topic

Any reason (other than cost :o ) that kept you from going with a 3.8L? From what I've read, you'd have the same VarioCam+ problems with the 3.6L or 3.8L. There is a guy on 6speed for whom FVD is doing a 3.8L swap into an early Boxster (eGas I believe), but they changed the ECU to a 7.8, and it seems like changing everything else to go along with it is complex/taking quite a bit of effort. Either here or on Rennlist, there is a guy who had made a controller to handle the VarioCam+. I can dig for it if you haven't seen it. I also really wish there was an intake manifold that would fit without having to lower the engine. Good luck with this conversion. I'm particularly interested to see how it goes. :notworthy:

Edited by mee
Link to comment
Share on other sites

Tool Pants, I hope that is a photoshop job.

Mee, I assume you are referring to John at Vitesse Racing, who says he has a way to control the variocam+ in the pre Motronic 7.X.X cars. i think I have an easier (cheaper) way of doing it and I will let you know how it works out.

Without having a donor car to transfer all the required pieces from to update to the later CAN bus electronics, I think the cost would be quite prohibative to get the later DME7.8 electronics to work in the earlier chassis. But this is always a possibility.

You are only dropping the motor ~1", the lowering at the front is balanced by different mounts at the rear. If you don't like lowering it, then use a Boxster S manifold.

I chose the 3.6 rather than the 3.8 simply because I got a great deal on the motor. If it works out, it will be no problem to drop in a 3.8 later when I can find one at a good price.


Link to comment
Share on other sites

I assume you are referring to John at Vitesse Racing
That's the guy. I have no idea how the VarioCam+ is controlled, but solving it has got to be easier than retrofitting the rest of the ECU, harness, instrument cluster, etc., etc.

You are only dropping the motor ~1", the lowering at the front is balanced by different mounts at the rear. If you don't like lowering it, then use a Boxster S manifold.
Are you sure? I didn't think the 986S intake manifolds would bolt up since the 996 intake uses those little ~2" spacer manifolds and the number of bolts is different unless you're talking 987S and PET is wrong. Not lowering the engine means you can fit the stock exhaust if ever needed. I saw that 9ff uses the X51 intake manifolds. I wonder if they are any different in height.

I chose the 3.6 rather than the 3.8 simply because I got a great deal on the motor.
I kinda figured you got a deal you couldn't refuse. Have at it! Thanks for the info as always...
Link to comment
Share on other sites

Lowering the engine has nothing to do with fitting the stock exhaust or not. The exhust mounts to the engine and tranny, not to the body. I ran my 3.4 with the stock 2.5 exhaust until the proper exhaust arrived. There is really no reason to not lower the motor and install the proper 996 intake. Ruf does it, that is good enough for me.

The boxster intakes bolt directly to the heads, the 996 manifold bolts to the aluminum intake stacks, that is why the bolt patterns on the plastic portions of the two intakes are different so I am pretty sure you could bolt an 'S' intake to the 996 head after removing the aluminum stacks.

I believe the X51 intake is the same height since the pictures I have seen of the ruf intallation uses spacers when installing that intake as well.

Link to comment
Share on other sites

I really liked everything about the 3.4. Nothing not too like, car dyno'd at 280hp at the wheels, runs just like a factory car with no issues. If I can't get the 3.6 to integrate in a similar fashion I will probably put the 3.4 back in and sell the 3.6. Or maybe sell the '99 with the 3.4 and pick up a post 2002S to stick the 3.6 in, that would probably make the most sense.


Link to comment
Share on other sites


You change motors like I change shoes... must be a handy guy to have around. In retrospect what did you like/dislike about the 3.4.

And I am still wearing the same shoes when the prof first changed his motor. :)

Good luck with the install, Todd. You know we will all be asking for a "how to" PDF at some point! :)

Link to comment
Share on other sites

  • 2 weeks later...

Spent Thurs-Sat swapping motors. The motor is in and it runs, at least well enough to get me back and forth to work. Just need to get some parts to see if I can control the cam timing and valve lift to get better driveability. It is definately quick, or maybe it just seems that way since Friday and Saturday I was driving my '84 944 around.

Didn't take any pictures, physically the swap is the same as the 3.4 one. Had to lengthen some of the original wires on the Boxster harness and I reused the 3.4 injectors and fuel rails so I don't have to upgrade the fuel system to the non-return system used on the later cars. Also used the 3.4 throttle body so I can keep the cable setup and not worry about e-gas.

I need to thank Loren for providing me the 3.6L engine wiring pdf on Thursday night, that was essential.


Edited by tholyoak
Link to comment
Share on other sites

A little info on my motor I found out.

It is a factory reman motor, installed in Dec 2005. The car it was installed in backed over a parking curb and according to the dealer had an oil leak caused by a crack in the case, they wouldn't fix it so it was replaced, paid for by insurance. The engine has 2600 miles on it.

Below shows the 'crack' in the case.


and the location of the galley boss on the case


Yep that is is, it is only in the oil galley plug casting, surface crack, the leak was probably because the oil galley plug (gold coloured plug with screw in it in the second photo) was knocked loose, a new oil galley plug and a little JB weld to fill the crack just in case and it is as good as new.


Link to comment
Share on other sites

yeah no big deal. Thats nothin some miracle JB Weld won't fix up. I would probablly put a hose clamp around that tho for a while just to make sure vibration etc doesn't cause the casting to crack anymore. I say that, even though I highly doubt that would even happen.

Link to comment
Share on other sites

Just a little update on the swap. Where the car with the 3.4 was fast, this thing is now scary fast. The torque difference between the 3.4 and the 3.6 is incredible. Don't know if it has to do with the variocam plus and the greater variation in cam timng, larger valves and lift but I am quite happy with the swap. The only 'issue' is that due to the greater cam timing variation in the variocam plus vs variocam, (40 degrees vs 25) the check engine light is on since the 3.4 program in the dme thinks there is a problem. Hopefully I can work with someone to reprogram the DME to get rid of this issue.

It makes some nice noises at full tilt, just better make sure it is pointed straight ahead when you push on the fun pedal.


Edited by tholyoak
Link to comment
Share on other sites

Hi Todd

I have been looking for a 3.4L engine for a while but can not get my hands on one. Maybe I will one of these days or now a 3.6 :).

Quick question: did you use your old gearbox (2.5L 5gear gearbox) and flywheel or did you also upgrade the gearbox. If I remember correctly that is what you had on your 3.4L?



Link to comment
Share on other sites


Yes I am in the US. I don't think it would make sense to ship it. Actually I am looking at picking up another Boxster to swap the 3.4 into and then sell the converted car. Easier than shipping the motor and a good way for someone to get a nice converted car at a reasonable cost.


Link to comment
Share on other sites


I've had my 3.6 waiting in my garage to go in to my 2.5 Boxster which I hope to do over xmas. What sort of signal are you going to provide to the variocam solenoid? I assume its not a straight nothing or 5volts as the solenoid appears to have 4 phase settings...

I believe the cam extra lift 'Plus' part is a straight 5v on to activate it.



Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.