Project 987.2 Porsche Cayman S, More Butt Kicking Power than the GT4!

If you have been following Project Porsche 987 Cayman S, you have been seeing the engine power parts we have installed as well as the mods to improve cooling and oiling. Now it was time to tune the ECU and PDK transmission controller to match the mods that we had done.  For our tuning we went to Mitch Mckee of M-Engineering.  Mitch has tuned our GT3RS with stellar results and we were confident that our Cayman would be in good hands.

For a tuning interface we used Cobbs Access Port. The Access Port enabled Mitch to access the maps for engine control and the transmission controller.

For the dyno, we used World Motorsports wind tunnel dyno. For tuning sophisticated newer model cars we use Worlds facilities because the dyno spins all 4 wheels and the wind tunnel has superior thermal management during tuning. A lot of late model cars freak out unless all 4 wheels are spun. The Wind Tunnel dyno uses the pictured huge fan to simulate road airflow.  Capable of wind speeds of up to 140 mph, the fan is linked to the dyno and matches the dyno’s road speed. This requires over 300 hp. It’s one hell of an electric motor spinning that fan. The World Motorsports dyno also has several other ducted fans to make for rapid air exchange in the dyno cell.  These smaller air exchange fans blow about as much air as a normal dyno fan and they cover the entire back wall!

Mitch is hard at work tuning the cars fuel and ignition tables.  Our car was running on the lean side which is to be expected since we really uncorked the engine. With adding a lot more fuel, the direct injection engine can now tolerate more ignition timing.

Wow, our Cayman now makes the distinct Porsche race car shriek. It sounds glorious but it is kinda ear splitting in the confines of the dyno room!   Our engine now makes a lot more top end power and the revs are increased to 7500 RPM.


  1. The 9A1 is just an incredible motor. Simple breather bolt-ons (albeit expensive ones) and tune have you well past 100whp per liter. That motor is literally make the same power per liter as the 4.5 liter V8 from the 458 Italia. Such an underappreciated engine.

      1. I shift manually, except for upshifts on straights at 100% throttle, where the car does it for me automatically. The 987.2 PDK is very good, but it’s not perfect so there are a few short moments on every track I’ve been to where it’s better to go manual. The 981 PDK shifting logic is much better, and I didn’t mind letting that car do all the shifting for me.

        1. Your car puts the power down very well at the corner exit! I was impressed by how early and how much you were able to get on the throttle.

          1. The car is set up pretty well, and the tires help of course. One guy with a GT4 refused to believe the engine wasn’t tuned because with a good exit, my car and a GT4 are about even below 90ish MPH.

          2. The 1:38.3 was on new R7s that I was trying for the first time. 37s definitely possible. I can do low 1:40s on NT01s, and 1:41s with PS4S. With aero your car is going to be crazy fast.

      1. Unfortunately no, other than the 3rd center radiator. The air temp was 57F and the coolant temp was 214F at the time of failure. Only within the last few months did I discover that transmission temps could be a problem, and I was considering adding cooling over the winter… now I’ll be replacing a transmission and adding cooling. 🙁 I’m going to at least get a larger PDK cooler, but I’m not sure which of the other items I’ll add.

        1. Did you see how we added a larger oil pan too? Your temperatures don’t seem too out of line. Do you know what failed in the transmission? Do you think the transmission could have starved due to oil slosh?

          1. Indications are the gear position sensor failed. I think it was due to heat but we don’t really know, and Porsche actively makes it difficult to find out. I wish I had access to the gear oil temperature.

            I did see the larger pans (thanks for the awesome in-depth articles btw). I think I’m favoring a second cooler for the transmission oil right now.

    1. Thats 320 hp at the crank, a dyno typically sees about a 15-20% loss through the drivetrain. So our engine is making about 400 crank hp.

  2. Impressive results ! Thanks for putting in the work to get it dyno tested.

    For the baseline run of 300hp and 251 ft/lb in the first graph, is that stock ? If that’s the case it looks like there’s very little drivetrain loss (6.5%) from the crank figure of 320hp. With the mods and putting 354hp to the wheels, it looks like it should be around 377hp at the crank which is almost in the GT4 territory.

    Also, in the second graph, is the dotted line with 302hp and 255 ft/lb supposed to be a stock GT4 or is it the stock Cayman S?

  3. I’d just like to point out a mistake in the article – “Our 9A1 engine went from 288 whp to 354, thats 66 more whp! Torque went from 251 lb/ft to 300 lb/ft, an increase of 49 lb/ft!”

    The torque actually went from 251 to 288 ft/lb (increase of 37 ft/lb) and the hp went from 300 to 354 whp (increase of 54 whp)

  4. To be fair, the stock GT4’s dyno is through cats and is full emission legal, isn’t it?

    Would love to see what kind of power your project car would put down while remaining emission legal. I think this would be a really fun street car!!

  5. Heya guys and gals

    Awesome project and write-up! Thanks

    There’s one thing here that I don’t get.
    I’m fully aware of crank hp and wheel hp, and that different dynos measure different results etc.
    However, you wrote on a comment that the car is making around 400 crank hp.
    However, isn’t it a lot more?

    If the GT4 which has an official 385 hp at the crank measured 302 whp at this dyno.
    Then if we assume that the GT4 has the official 385hp and use that to calculate the loss, and apply the same numbers to your Cayman then the actual crank hp would be around 451hp!

    Am I missing something here?

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