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PCA / POC Member & Club Donor
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Discussion Starter #1
Delayed Thread - Originally Posted 1/6/19

Background:

With Vision Motorsports, we built a 2007 987.1 Cayman S race car over 10+ years, developing the chassis from an AX car, to time trial, to street stock club racing, to GT class leader. The most recent configuration was a 4.2L M97 engine with a short ratio G87.21 six speed manual. While the car was quite successful, winning 5 POC GT3 class championships and setting multiple track records, long-term reliability of the M97 derived engine was limiting further chassis development. And the introduction of the PDK GT4 Clubsport was threatening our competitiveness on tracks with multiple full-power up shifts (data indicates approximately 0.1 - 0.15 seconds per shift). Photo below:

New Rockers - Crop.jpg

Plan:

Update the 2007 987.1 to a 2011 987.2 DFI/PDK and increase power by swapping the stock 3.4L DFI engine for a 3.9L 9A1 race prepped DFI engine (bored from a long stroke 3.6L Carrera engine)

Execution:

We sourced a running 2011 Cayman S PDK with Sport Chrono and factory LSD (which had already been updated with a Guard LSD) to serve as a donor for the engine core, PDK, chassis and engine harnesses, ABS pump, fuel pumps, all computers (engine, PDK, climate control, etc), dash, shifter, etc. We estimate that this was the most cost effective way to obtain all required parts that were known to work reliably together.

Vision Motorsports techs stripped the race car and donor and began to transfer all required parts while the engine builders modified the Carrera-based 3.9L DFI engine to work in the Cayman, including transferring all ancillary parts and improving/updating other parts as needed (oil cooler, intake plenum, etc.). The engine and transmission were then mated and test fit into the chassis and ensure that everything clears the diffuser (not shown).

The team then identified anything that needed to be modified to work in the legacy chassis. While most parts were direct bolt on, we did need to source new headers (M&M 987.2 race headers), fabricate new exhaust, fabricate new rear ARB and mounts to compensate from the previously modified rear sub-frame, rework the prior engine oil cooler to serve as the PDK gearbox cooler, install a larger PDK ATF cooler, install the 987.2 bumper and taillights (and headlights), and re-work the AiM and radio systems. We also decided to use the GT4 Clubsport factory steering with with integrated paddles as it is plug and play with the 987.2 wiring system.

All work was completed over a two to three month period by a single, experienced Vision Motorsports tech (with occasional support from other techs).

Results:

The car is nearly complete and is currently testing on the dyno (tune refinement). Early results are excellent and all systems appear to be working together properly. Our first on-track test is this coming weekend at Willow Springs. Following what we expect to be a successful test we will update the PDK software and make a few additional changes (headlights, cooling ducts, etc.).

Here are several photos from the update:

Build 9.jpg

Build 7.jpg

Build 2.jpg

Build 3.jpg

Cheers,
 

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Discussion Starter #2
The car is running well, but we still have a bug or two to work out with the ABS. We were told that the new FVD PDK programming would allow us to run the car in sport or sport plus without the yaw sensor to improve stock ABS performance, but this was not the case. The programming did improve shifting, but did nothing to help our primary issue. So, until FVD or another vendor can get this worked out we are stuck needing to leave the yaw sensor on and the stock ABS in the car to run the PDK in Sport Plus. This is a significant step down in braking performance from the Teves Motorsports system we ran previously. Alternately, a local shop has figured out how to connect a Bosch M5 Motorsports unit into the PDK using a Motec dash. So, this may be the route we need to take, but I am not looking forward to the bill.

We are racing the car this weekend at Buttonwillow after a few minor improvements, unfortunately none that will help the braking. Our last outing was at Willow Springs in a mix of rain and dry. Other than the braking issues the car ran flawless and and is already approaching previous performance limits.

Here is a photo taking after a day of racing in the rain:

Willow 02 03 19.jpg
 

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Do you use the ABS unit together with the can bus Yaw sensor for 987.2 cars?
You might be able to use a gt3 997.2 abs pump which has better brake performance. Small adaption in the DME is needed.
Andreas
 

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Discussion Starter #5
Do you use the ABS unit together with the can bus Yaw sensor for 987.2 cars?
You might be able to use a gt3 997.2 abs pump which has better brake performance. Small adaption in the DME is needed.
Andreas
The current (stock) ABS does not require the yaw sensor to function, and actually works better without the yaw sensor (better overall performance, no/reduced ice pedal). The issue is that PDK computer requires the yaw sensor to operate in Sport or Sport Plus mode, so shutting off the yaw senor significantly reduces shift speed, etc. - even post the FVD "upgrade" to the programming.

Do you have direct experience with using the 997.2 GT3 ABS with the 987.2 PDK computer? You said "might". Also, if you have made this work, what changes are required in the DME?

Thank you,
 

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Hi, yes I said "might" because I am currently testing with a 997.2 GT3 ABS/PSM unit. Not working yet. Have cayman 987.1 (see https://www.pff.de/index.php?thread/2791270-cayman-987-turbo-real-tuning-totgesagte-leben-laenger/)

Having the same series, or 997.1/987.1 or 997.2 / 987.2 electronics , canbus, etc. usually are pretty interchangeable.

For example if you have a 997.1 ABS/PSM module in a 987.1 then you can reprogram the gateway with durametric to 997 and you modify code in the DME, both modifications will remove the "incorect version" error thrown from the ABS/PSM.
The code change in the DME is only the MOTORVERSION, this is a byte and differs for (0 => 3.4 cayman, 2=> 997 3.8, 3=> 997 turbo , 9=>997.2 gt3 )

I am currently trying the 997.2 GT3 ABS/PSM unit in the cayman , but there are still errors and in the next month I will check can bus communication to understand better.

By the way, you do not need to remove the whole abs/psm unit, it is sufficient to change the black electronic box only, the mechanical part is identical.

In my case I have a 987.1 car electronic with a 997.2 gt3 abs/psm unit. This is trickier, as there are differences between facelift and before facelift cars.
The older abs/psm unit has a direct connection to the yaw sensor. The .2 system has the yaw sensor connected to can drive. Also some wiring relative to PSM on/off button is different.
Another difference is the sport mode handling.

Relative to yaw sensor switch off: This is a solution proposed by Scott long time ago for the 987.1 cars. There the yaw sensor is directly connected to the abs/psm unit. Cutting a signal wire off then the abs/psm unit will then always think that you are driving on a straight line.
On a 987.2 car the yaw sensor is via can bus. Does it work also? On my car the 997.2gt3 abs/psm unit complains about a missing yaw sensor if I disconnect it. So I would double check if Scott's trick still works on .2 cars.

Your car is a 987.2, so a 997.2gt3 unit would be of the same dev level (both .2). If you have one at hand, give it a try!
If you check the parts catalog then I find that car electronic is same for a 997.2gt3 and for a 987.2 2.9 cayman. So there just by software adaption (DME and gateway) one should get it to work.
You have a 987.2 dfi DME, ok , it is different, but I would expect can bus management identical to the 987.2 2.9 DME.

PDK: No idea about pdk programming. But the motorversion byte probably exists also there, so it should be possible to adapt it.

Base idea is to make believe the abs/psm unit (which cannot be modified) that it sits inside a 997.2 gt3 car.

good luck
Andreas
 

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Hi Guys. Random question. I'm looking for a gt3 ABS control module for gt3 997.2 my cars is a 2010.

Does anyone have one to sell?

Thanks

Greg
 

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Hi, yes I said "might" because I am currently testing with a 997.2 GT3 ABS/PSM unit. Not working yet. Have cayman 987.1 (see Cayman 987 turbo real tuning, Totgesagte leben länger - Porsche Forum & Magazin - PFF.de)

Having the same series, or 997.1/987.1 or 997.2 / 987.2 electronics , canbus, etc. usually are pretty interchangeable.

Base idea is to make believe the abs/psm unit (which cannot be modified) that it sits inside a 997.2 gt3 car.

good luck
Andreas
hi Andreas,

Any updates on this? Because I find your approach very interesting because it goes at the root cause (a trigger happy standard psm), rather than trying to cool breaks better etc.

I can’t seem to find the part number for the 997.2 gt3 Psm controle module. Does anyone have it?

regards,
hans
 
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