3.4 swap issues, and an alternative to lowering engine 1.5"

[Bigsmoothlee]

Hey guys, brief intro, my name is Lee and I manage a german car specialist shop here in northern nj. I bought a 2000 boxster with a blown 2.7l engine to swap in a 3.4 I had laying around.

Ive been very busy recently in the shop and havent had much time recently to work on my 3.4 swap...that along with the fact that ive also been dividing my free time to working on my 944 turbo as well...

So I came across this issue, the roads in my area arent the greatest, and im a bit skeptical of lowering the engine/transmission assembly 1.5". Im sure some of you guys in the south are wondering what im talking about, but the roads out here are HORRIBLE. I feel its really a poor solution, especially for anyone who is planning on lowering their suspension in the future.

In addition to that, I have been talking to a few big Pcar tuners telling me my particular situation is difficult. Here are some road blocks to tuning my ECU :

1. I need the VIN for the 996 I removed the engine from, which I dont have.

2. When I offer to send over the ecu from the 996 engine so they can pull the VIN out of it, they tell me its another issue because the 3.4 has a cable operated throttle, and the 986 ecu is an egas throttle, and it can not be changed.

3. Then they tell me I should convert the car to a mechanical throttle setup, and use the 996 ecu in the car, but how would I get that to start with the 986 immobilizer blocking it??

So to avoid all this frustrating mess, I plan to install the engine with the 2.7 intake manifold installed, and find someone to tune it. But for the time being, the engine will start and drive with no issues.

The 2.7 manifold does not bolt on to the 3.4 heads, but Porsche did leave the mounting points blank, so you could actually drill, tap, and bolt the manifold to the engine. Im in the process of doing it, Ill take some pics, and post them up. The intake ports need some porting for the injector spray pattern as well.

I realize this will remove about 20hp from the motor, but its worth it if it keeps the lower part of the engine block intact over bumps. Maybe this is why the early boxster S 3.2 makes a lot less hp than it should? A restrictive exhaust system and
this type of manifold arrangement?

I wonder what the newer 987 intake manifold looks like... im pretty sure the engineers at porsche didnt want to mount the engine lower either?

[manolo]

Its expensive, but someone has used the 996 X51 OEM optional intake instead. Its all aluminum and has a shorter profile that clears the engine bay in the Boxster. Search around for that, I believe it was Cloudsurfer that did it. Then you get the best of both worlds, more power and dont have to lower engine. The downside I imagine is cost.

[JAAY]

Bolt a E-gas throttle body to the 3.4 manifold, get ALL your codes from the dealer on the stock 2.7 ecu. Send the ecu to pedrosgarage.com and he can pump in the 996 egas map into it. Don't worry about lowering the engine. It only has to go down about an inch or less.. Mine is about an inch lower and I have coil overs and am pretty low. Roads suck here too! You do not need the vin from the car that the motor was removed from. It has nothing to do with the ecu that the car already came with. I may be wrong about all this but I have an egas motor in my car and all i did was swap the throttle body. Same motor otherwise. Contact Pedro for real technical questions. I can help with the swap otherwise if you have other questions.

J

[JAAY]

You also may need a new center section on the manifold to fit the E-gas throttlebody. You may be able to use your 2.7 throttle body still and center section that it is already attached to. It's worth a try.

[JFP in PA]

Originally Posted by Bigsmoothlee

So I came across this issue, the roads in my area arent the greatest, and im a bit skeptical of lowering the engine/transmission assembly 1.5". Im sure some of you guys in the south are wondering what im talking about, but the roads out here are HORRIBLE. I feel its really a poor solution, especially for anyone who is planning on lowering their suspension in the future.

One point that you are overlooking is that lowering the engine and transmission significantly lowers the car's center of gravity, which has the effect of improving the car's handling...........

[insite]

Agree w/ jfp. Lower cg is good. My 3.4L is LOW w/ no problems.

[Bigsmoothlee]

Originally Posted by manolo

Its expensive, but someone has used the 996 X51 OEM optional intake instead. Its all aluminum and has a shorter profile that clears the engine bay in the Boxster. Search around for that, I believe it was Cloudsurfer that did it. Then you get the best of both worlds, more power and dont have to lower engine. The downside I imagine is cost.

Insite suggested the same, looks like they are expensive new, ill just keep looking for one in the meantime. Hopefully one pops up for sale around spring. This, is a way better solution.

Originally Posted by JAAY

Bolt a E-gas throttle body to the 3.4 manifold, get ALL your codes from the dealer on the stock 2.7 ecu. Send the ecu to pedrosgarage.com and he can pump in the 996 egas map into it. Don't worry about lowering the engine. It only has to go down about an inch or less.. Mine is about an inch lower and I have coil overs and am pretty low. Roads suck here too! You do not need the vin from the car that the motor was removed from. It has nothing to do with the ecu that the car already came with. I may be wrong about all this but I have an egas motor in my car and all i did was swap the throttle body. Same motor otherwise. Contact Pedro for real technical questions. I can help with the swap otherwise if you have other questions.

J

I spoke to Pedro, he was very helpful, but he was the one who told me all of the above (with the exception of the manifold) Ive already drilled one side for the 2.7 manifold, and one side to go for now.

Originally Posted by JAAY

You also may need a new center section on the manifold to fit the E-gas throttlebody. You may be able to use your 2.7 throttle body still and center section that it is already attached to. It's worth a try.

Negative on both Jaay. The mechanical throttle mounting points are not symmetrical like the egas. Also, I tried using the center section as well. Its identical, however the 2.7 is about 15mm smaller in diameter than the 3.4. Ive thought about bolting in the center section from an egas 996, which brings me back to problem #1.

Originally Posted by JFP in PA

One point that you are overlooking is that lowering the engine and transmission significantly lowers the car's center of gravity, which has the effect of improving the car's handling...........

Originally Posted by insite

Agree w/ jfp. Lower cg is good. My 3.4L is LOW w/ no problems.

I went to school to become a mechanical engineer, and there is no doubt in my mind this would help lower the cg, but I believe this is a solution with far more negative side effects than positive.

Its not only lowering the engine that bothers me, its the shear force being applied to the mounting bolts at the front engine mounts as well. Of course, during acceleration its not an issue, as the engine will be applying clockwise force on the four bolts, effectively pulling 2 straight down, and pushing the other 2 straight up.

However, during braking and cornering has a tendency to push forward, or to the sides as well. At the very least, you guys should have 1.5" metal spacer plate made, and not trust those poor bolts and thicker hardware store washers to do all the work.


Guys, so here is what I have been up to after work. Please keep in mind that between 8am and 6:30pm, I am working on clients cars. This is strictly after work, so progress is slower than what I would like it to be...

By the way, I removed both cylinder heads from the 3.4 for the following reasons

#1. I never just install and engine and throw it in the car (clients or my own) You can never trust the previous owners claims of maintenance or mileage.

#2. Drilling the heads is much safer, and there is no worry of metal shavings going into the engine

#3. I wanted to do a mild port and polish job (more like a clean up with a mirror finish on the intake ports)

#4. Im going to change the valve seals, check the valve guides, and lap the valves. Also, new chain tensioners and chain rails are going in.

And believe me guys, the engine is filthy now, but it will be looking brand new before it goes in the car.

[Overdrive]

I've gotta see this...

[Bigsmoothlee]

Ok time for an update, sorry ive been out enjoying the car with the 3.4 recently

Well so far lets see what this swap has cost me...
About $120 in gaskets
$595 for an ln engineering ims bearing

and thats it. This swap was done without altering anything in the car, no switching pins in the ecu connector, no chopping, everything looks stock. the check engine light did come on, but because of an O2 sensor.

I used the stock 2.7 manifold, 2.7 exhaust, and 2.7 ecu. The car runs excellent.
Lots of Torque in every single gear. The power does seem to fall off after 5500rpm, mostly because of all the restrictions. But it still does pull to 7200

Im very happy with the power for now, and theres no reason I need more at the moment. Winter is here, and the car is already on snow tires.

So here are the plans. Im going to go with a X51 intake manifold, full exhaust, and a good tune as soon as the snow clears. Pics soon to come

[insite]

who will tune it?

[Bigsmoothlee]

Not sure yet, but before I do...
If im going with the electronic throttle, and an X51 intake manifold, who is best to use?

[Jake Raby]

This will certainly work.. I first did this in 2007.
The compromise comes in tuning around the smaller intake volume and the fact that the RPM range will be impacted.

[insite]

Originally Posted by Bigsmoothlee

Not sure yet, but before I do...
If im going with the electronic throttle, and an X51 intake manifold, who is best to use?

i use the OEM 3.4L program from the 996. one of the board members (todd holyoak) did it for a great price. do you have the VarioRam hooked up yet? you'll want to do that.

[Bigsmoothlee]

Originally Posted by insite

i use the OEM 3.4L program from the 996. one of the board members (todd holyoak) did it for a great price. do you have the VarioRam hooked up yet? you'll want to do that.

Just a question about that,
Will I need the VIN from the old engine? Because I dont have it
I have the 986 system in place on the manifold, and it works. If I were to swap to a 996 program, would I have to move some wires around on the ecu connecter?
thanks

[insite]

you just need the VIN from the car. take it to a dealer w/ proof of ownership & get the immobilization codes.

as to the extra wires? you will want to run a wire from the ECU to the varioram flap. it's worth a lot of HP up high.

[Brad Roberts]

lol

CaymanS engine cover fits right on. It's raised in the middle. You have to transfer the 986 DZUS fasteners and add a washer to them. The 987 engine cover is alum and much thinner/lighter

Every car I crawl underneath with a lowered 3.4 has beat up headers... every one of them.

Want to make more power? Install the CaymanS air box in the 986. It requires removal of the *muffler* chamber and slight movement of the vent line from the gas tank

I'm tired of seeing all the "hot air" intakes other shops have used in the past.


B

[jaykay]

Are you able to get the Cayman box in with out engine removal?

Do these fellows finish the engine cover for sound and carpet or are these strictly track cars? Mine buzzes like crazy with no cover on the cover

[Brad Roberts]

I can

The CaymanS snorkel can be installed from outside the car, so yes you can install it with engine in the car. It *will* require removal of the drivers side plenum, but the plenum doesn't need to come out of the car, just flip it up and over.

FYI: get the CaymanS MAF holder also..

[Brad Roberts]

More info (I'm in the giving mood with the holidays and all)

Cars without a fuel return line (02 and up) will have to move nothing when it comes to lines

[onaFLYer]

Originally Posted by Brad Roberts

lol

CaymanS engine cover fits right on. It's raised in the middle. You have to transfer the 986 DZUS fasteners and add a washer to them. The 987 engine cover is alum and much thinner/lighter

Every car I crawl underneath with a lowered 3.4 has beat up headers... every one of them.

Want to make more power? Install the CaymanS air box in the 986. It requires removal of the *muffler* chamber and slight movement of the vent line from the gas tank

I'm tired of seeing all the "hot air" intakes other shops have used in the past.


B

I just did the Cayman S air box install in my own 986. And yes it fits right in, once you remove the sound muffler/chamber off the back. I also "adjusted" the area around the MAF upper clamp. My engine is out, I would imagine its a tight squeeze with engine in car. I can add some pic's if anyone is interested.