I can't recall if you got the COBB tune also with the headers, too lazy to read again old posts...if you didn't let me share my experience doing exhaust and no tune. I did almost one after the other, the CG sport headers and Cup race exhaust system. Car felt great and you could feel the extra power but I was also detonating a bit sometimes (even with 93 gas).....after a few months I decide to give the COBB AP a try and guess what....the car was so lean I was loosing power on the top end. After a custom tune I gained a very respectable amount of power across the board and no detonation....so think about that Tune if you don't have it yet.

 

When is the cat version coming???

 

Were you running the stage 2 OTS map? That should correct the lean w/ headers issue.

 

What are you planning to do to address the detonation issue?

 

Duplicate

 

We're planning on getting it prototyped in the next 6-8 weeks.

 

The car is running great. I think my comment was misleading. What I was trying to say I though the car while on Dyno and PCM not adapting it felt like it was detonating but this is all gone after PCM adapted. Car is running great and no plans to do anything else.

Current modern engine designs won't allow engine to detonate, and the PCM would alter fuel and timing before this would ever happen. I am used to the old days and was just describing how the car felt on Dyno. Most likely what we felt on Dyno was the PCM pullling timing and as a result the car doesn't see to be happy. The good news after PCM adapted never felt any issues and car is running great. Mark

 

Hi jmartpr. No I did not get the tune and I am staying stock. I am currently concerned with Porsche warranty and especially with transmission failures and few other issues. Currently the car is runny amazing so there is no need for me to experiment with tune.

I think I may have mislead you with the loose use of the term detonation. Honestly I don't think a modern Porsche engine would ever is alloweed to detonate as the PCM would not permit it. But indeed the car as not happy while on Dyno and while PCM not adapted, and probably PCM was pulling timing or altering fuel ratio, etc which felt like the old days when the old egine is detonating. So what I meant to say engine was not too happy. After car is out of warranty I plan to experiment with tune, and really appreciate you trying to help me, and would be great if you could pm me more info on the tune. Mark

 

The detonation in my case was not under full throttle....was more likely to occur if the revs dropped under load like maneuvering the car up an incline or into the dyno (hope that makes sense)....anyway, from day 1 of installing the COBB AP we did a full custom map. It was way better than the OTS maps. Tuner spent probably 3-4 hours playing with different options and started with a map from another modified GT4 with a different setup but was a good starting point.

 

Hi Mark...no problem, let me know any questions. If my setup with cats did benefit from the Tune I believe a setup without cats could get even better results with the tune.

 

And sound even hotter!

 

Any more reviews?

 

Anymore reviews or Dyno verifications

 

We have a second car coming in next week for the same tests as we performed earlier. We will post results again.

 

As more and more are looking to dyno their headers, please follow the procedure below. This is how we've done it and the car appears to be sensitive to the adaptation, more than we would have expected. MQandil shared his experience, unfortunately he wasn't able to make it in last week for the repeat dyno.

Another item to note is the headers are designed to work with the stock Porsche Sport Exhaust, other after market exhausts are different than the stock system and will effect the resonance tuning of the Dundon headers.

Steps to correct dyno procedure.

**** all dyno runs need wheel well exits blocked off from fresh air inlets. Typically we use cardboard as it's easy and readily available

**** all dyno runs need fans blowing fresh cold air at air inlets.

1) dyno vehicle stock. Do atleast 3-4 pulls with sport on and exhaust button on

2) install Dundon headers. Install air filters.

3) drive vehicle on stock ecu with headers for atleast 1 full tank of gas. Need to drive enough to allow the ecu to fully adapt.

4) dyno vehicle again. Sport on exhaust flap on. Do 4-6 pulls to be sure vehicle has settled and adapted.

5) install Cobb and flash vehicle. Drive atleast one tank of gas to allow to adapt.

6) dyno vehicle with flash. Atleast 4-6 pulls.