Project 981 Cayman - Pro Tuning / Final Power Numbers (Episode 9)

Project 981 Cayman - Pro Tuning / Final Power Numbers (Episode 9)

Project 981 Cayman - Build Series

Power Additions

We have wrapped up the final tuning of the Project 981 Cayman in terms of power. We were able to dial in a few more HP with our custom Pro Tuning. Here is a list of all the power enhancers to recap:


  • RunFile_001: 100% stock
  • RunFile_002: All parts listed above running COBB OTS Stage 2 Map
  • RunFile_003: All parts listed above running Flat 6 Pro Tune Map

Dyno Analysis

It's easy to reference the peak numbers and feel a sense of disappointment with all the power adders that were added. However, it is important to look at the dyno plots and see the "area under the curve" to understand that gains were made across the complete rev range. Most notably around 6500RPMs were we picked up 34.4WHP gain over the stock vehicle. (Note - During our first test we used the rolling speed of the dyno rollers as it was too difficult to get to a sensor for the dyno to translate RPMs. To remain all conditions consistent, each dyno session, we replicated the same conditions on all runs). The final tuned power came in at 17.1WHP over the stock number. To reference this to flywheel gains, we simply see the peak gains were 7.5% over stock. Applied to the 275HP number from the factory, this implies our Project 981 Cayman is making roughly 295HP.  Not too bad out of a 2.7L naturally aspirated engine that was already tweaked fairly good from the factory. 

Butt Dyno 

Dynos are a great way to show the change in power but at the end of the day the experience of driving is drastically different compared to stock. Of course we have a lot more audio with the headers/exhaust but the Cayman is much sharper with throttle response and mid-range torque is drastically improved. We can feel more power all over the powerband and most notably on corner exit. The car digs out and gets on it's way much quicker making it a much more fun car to drive on back roads and soon the track!

Data Acquisition (Where The Rubber Meets The Road)

Feeling is great, but data is important when analyzing the impact of performance modifications. Our goal was to get to the acceleration of a 987.2 Cayman S. Not sure we succeeded without testing but it feels pretty darn close. Using our QSTARZ Q6000S GPS Lap Timer we performed several 30-80mph runs. This device can snag the attention of 20+ satellites and use super fast refresh rates to dial in very accurate numbers. We were blown away with our final acceleration times. The temps were a fair bit cooler outside (stock was 72 degrees where final power numbers were 47 degrees ambient) but that shouldn't impact acceleration too significantly. Below are some historical acceleration figures over the course of the build. Removing nearly 1.5 sec from 30-80mph is quite an accomplishment and makes us feel even better compared to the dyno plots. 

Acceleration Numbers (From 2nd Gear)

30 - 80 MPH Time (Sec) Distance (Ft) Time Diff Distance Diff
STOCK 7.626 648.17 - -
COBB STAGE 1 OTS 7.007 583.59 -0.619 -64.58
w/ IPD PLENUM  6.921 578.21 -0.705 -69.96
FINAL POWER 6.177 517.72 -1.449 -130.45

Final Impressions

We think the power additions were a common set of simple bolt-on parts to round out the 2.7L Cayman in terms of power. We are happy with the gains although we would have loved to push the peak number some more. At the end of the day, you have to evaluate what your goals are and what budget you want to put against it. We're having some fun with this build so can't sit here and say do all of these mods because for some people it might not make any sense. Most Porsche owners aren't comparing HP to Dollar ratios like Mustang owners but there is something to be said about the overall effect on power for the investment and ease of install. 

Now that we have the power side sorted out, our next project is installing the JRZ RS2 Touring Coilovers. 


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