2.7 to 3.6 swap

[tholyoak]

You might want to reconsider the piggy back solution. While it will be easier and cheaper I doubt you will be happy with the result. Further it will require custom DME programming to deal with the larger amount of cam timing changes (40 vs 25 degrees) on the 3.6 with the vane type adjuster vs the earlier cars with the ramp type cam timing adjusters. Further, unless the new SMT controller provides PWM output, the all or none switching on the outputs for cam timing and lift are not going to give you the drivability you want for a street car. The all or none effect is fine for a full-throttle-all-the-time track vehicle but I doubt you will like it on the street. You can eliminate some of the drive-ability issues with custom ECU tuning but this will cut into the cost savings you are hoping for. This is how Rook does their conversions so some may not agree with me. While it may be harder at the outset, if you integrate the 7.8 DME you will get a car that runs and can be diagnosed like a stock vehicle from Porsche.

-Todd

[phillipj]

I absolutely agree with Todd. I have the Roock 3.4 to 3.6 conversion and it is a compromise. Although the Vario Cam 'Bump" at 3k rpm is better than it was it will never be a smooth as a factory set-up.

As light as the Boxster is be ready for it to be a handful when that power kicks in at 3k. :drive:

I don't mind it but some people would hate it. It's like a nitrous shot at 3k rpm. I'm doing some re mapping of the power band to make it more drivable but it will never be as civilized as stock. I guess it depends on what your needs and expectations are.

A tech is going to work on the car one more time this month and I will of course post the results.

Good luck with whatever route you decide to pursue. :D

[Guest]

Thank You both for the input. I will start with the piggy back solution; It will be delivered today actually. It's the new model SMT8 and seems to be more capable than the old one. It does have PWM:

. I will get the engine to work with the SMT8 for now.

Latter I will do the full conversion (I need to keep something to do for the winter also). I do have a tip harness and also the dme/imobilizer and key fob from the 3.6 for a factory stile conversion.

Phillip: Do you have a Wiring diagram from your conversion by any chance?

Here are the specs for smt8:

" The SMT8 piggy-back unit follows in the footsteps of the SMT6 and SMT7 units, but with unparallel performance and a quantum leap of technical innovation. This is all possible with the latest 16bit DSP processors, crammed full of features never seen before. This unit is for the professional tuner and engine builder.

One of the new features is the fully programmable engine protection which monitors the engines performance, and should anything exceed the specifications then it gradually reduces engine power after a programmable time delay. Absolute Magic!

Of course it has multiple analog modification channels, frequency and dual lambda modification. It can control boost PWM and has three bipolar ignition channels for one crank and two CAM signals. The two direct injector drives can be used as set point controls and can be mapped independently for fuel injection.

The mapping of all this is done via a high speed USB port and the user friendly LetRipp PC

· 2 Maps to influence analog signals

· 1 Map to influence up to three ignition signals

· 2 Extra injector maps to drive two injectors

· 1 Set point control with up to 3 outputs (relays)

· 1 Frequency modification map

· 1 AFR (Lambda) modification map wide/narrow

· 1 Boost control screen

· Calibration of all inputs: Engine Temperature, Air Temperature, AMP (MAP) Sensor, Throttle Position, RPM, Ignition cut, Ignition retard, ETC.

· Engine Protection via: Ignition software cut, Ignition retard, ETC control

"

[Guest]

I got the piggy back; just starting to study.

[phillipj]

Sergiu,

I don't have the wiring diagram because Roock wont disclose his method. I'm very interested to see how your piggyback solution works with your new software programmer.

On the surface it sounds great. It may be somthing I would consider if you have success with it.

Please keep us posted. I'm anxious to hear how you get on. Sorry I can't be of more help.

Phillip

[Guest]

Engines side by side today.

[txhokie4life]

Engines side by side today.

way cool!

m

[Guest]

Striped down 3.6; switching things aound. :beer:

[phillipj]

Excellent...Keep the updates coming

[Guest]

today: changes the injector rails to boxster - no return for the fuel tank - did keep the 996 injectors; compressor from the boxster(made in japan?!) - better shape; changed belt; harness from the boxster engine; connectors from the 996 harness for the variocam plus solenoids and the cam sensors.

Edited June 26, 2009 by sergiu

[catmanluge]

today: changes the injector rails to boxster - no return for the fuel tank - did keep the 996 injectors; compressor from the boxster(made in japan?!) - better shape; changed belt; harness from the boxster engine; connectors from the 996 harness for the variocam plus solenoids and the cam sensors.

Be careful mounting your injector rails. I used the 2.7 rails on a 3.6 and had the injectors to deep into the manifold, it cost a big power loss.. .020 of an inch difference made a big change in the power band. You really can't notice until you are running full throttle in higher gears..

[Guest]

Quick update: the engine is in, droped 2 inch in the front, none in the back.

Injector rails from 3.6 back in. Fuel pump ordered.

Dme 7.8 going in on Monday. All the diagrams studied hard and this seems to be the best solution.

Boxster 2004 instrument cluster in the mail.

Still need the can hvac , but that can wait till winter

factory headers on for now.

The engine to start on Monday. Keep fingers crossed

Sergiu :renntech:

[Guest]

nobody kept they fingers crossed on Monday - failed to start - first blamed the immobilizer; found out to be an unconnected wire 2nd to wrong diagrams.

So Tuesday started but no throttle response.

Today finished the intake and still running in 3 cylinders - found out that the engine was floding 2nd to 5.6 bars in the injectors rails.

996 new pump in ; level indicator in the mail to arrive in am. Hopefully a smooth run tomorrow.

Also did not install yet the instrument cluster and the headers are factory for now; the new ones are in the mail.

Some pics of the new dme with marked extra wires and the tight fit of the engine (before the custom intake).

I worked on he wiring diagrams but otherwise all the credit goes to my local installer/tuner - they are amazing at figuring things out as they go.

:drive:

Sergiu

Edited July 9, 2009 by sergiu

[phillipj]

Excellent updates. Keep them coming.. I wish you success on a smooth run next time!! :jump:

[Guest]

:(

What a blast; too bad it lasted only half a mile...

Was fun to feel the tiptronic spining wheels while changing to 2nd and 3rd. Scary fast in all rpm's.

Too bad that I found the hard way that 2 inches lower for the engine it's a lot. I hit a water storm drain while changing to 3rd and blew the oil pump cover, dented the new headers; O2 sensors; chiped the oil pan. Back to the mechanic to fix those and fabricate an aluminium skid plate to be attached to the frame.

[ziiz996]

That sucks!! Sorry to hear that... Don't mind me asking but how much $$$ are you out so far?

[catmanluge]

:(

What a blast; too bad it lasted only half a mile...

Was fun to feel the tiptronic spining wheels while changing to 2nd and 3rd. Scary fast in all rpm's.

Too bad that I found the hard way that 2 inches lower for the engine it's a lot. I hit a water storm drain while changing to 3rd and blew the oil pump cover, dented the new headers; O2 sensors; chiped the oil pan. Back to the mechanic to fix those and fabricate an aluminium skid plate to be attached to the frame.

Engine height

I lowered my engine 1.5 inches in the front and 3/4 of an inch for the trans mounts. Cut a small grove in the under side of the firewall just above the intake manifold and file the intake manifold ridge 1/4 of an inch. No problems..

Have fun!!

[txhokie4life]

Is it easier to raise the engine by modifying the housing top area?

m

[Guest]

That sucks!! Sorry to hear that... Don't mind me asking but how much $$$ are you out so far?

Did not put the numbers togheter as that may be dangerous in the way that I will have an answer when the wife will ask the same question. Ballpark should be 12000.

[Guest]

:(

What a blast; too bad it lasted only half a mile...

Was fun to feel the tiptronic spining wheels while changing to 2nd and 3rd. Scary fast in all rpm's.

Too bad that I found the hard way that 2 inches lower for the engine it's a lot. I hit a water storm drain while changing to 3rd and blew the oil pump cover, dented the new headers; O2 sensors; chiped the oil pan. Back to the mechanic to fix those and fabricate an aluminium skid plate to be attached to the frame.

Engine height

I lowered my engine 1.5 inches in the front and 3/4 of an inch for the trans mounts. Cut a small grove in the under side of the firewall just above the intake manifold and file the intake manifold ridge 1/4 of an inch. No problems..

Have fun!!

I think the way you did it it's better. I did lower only the front 2 inches; none at the tip mount.

[phillipj]

That sucks!! Sorry to hear that... Don't mind me asking but how much $$$ are you out so far?

Did not put the numbers togheter as that may be dangerous in the way that I will have an answer when the wife will ask the same question. Ballpark should be 12000.

:o :jump: :jump: :jump:

[juniinc]

excellent work! sergiu

Who's doing this for U? U?

[Guest]

excellent work! sergiu

Who's doing this for U? U?

My local tuner it's doing most of the work; I did the dme swap work.

[Guest]

update: after hitting the engine , messing up the timing the car is back on the roads with a skid plate. Got it from the shop on friday. On the way home had the chance to race a Boxster S - crazy enough lady to race up to 100 miles on a city street. Car did keep an advantage over the S. At 80-100 miles I had to shift early as it seems that was not getting enough fuel at high speed, high rpm's. I guess I will need to take it at the dealer to remap the dme for the custom intake/maf. Also the gas pedal is very sensitive/too responsive. The car runs just fine otherwise.

The car has plenty of power and the tiptronic it's holding fine so far.

Sergiu

[mattNY]

Awesome project, thanks for the pictures along the way.