Originally Posted by wrs

The stock ECU has no power loss with the headers, there is a power gain across the RPM range against the stock components. The car makes 52hp more than stock with boltons only. The variable in your setup was not the headers, it was the tune. Note that the addition of the FVD piggyback produces a similar power loss in my dyno data. So please tell me how you can blame the power loss on the headers? The data contradict your conclusion.

Originally Posted by sdg1871

All that I know is it with the GIAC tune, regardless of what they did to it, there was power loss which is why I removed the FVD headers.

Originally Posted by Markblackwell

wrs, this was done on a Mustang dyno, and it lost power both stock and modified ecu with and without tweaks. I loved the sound from this setup, but I bought this system for sound and performance so Im a little pissed it didnt perform, making less than stock is unacceptable. Im glad you had good results with your setup.

Originally Posted by sdg1871

Stated differently it was immaterial to me whether the FVD headers gained power with the stock tune because I was never going to be using that tune.

Originally Posted by Markblackwell

wrs, this was done on a Mustang dyno, and it lost power both stock and modified ecu with and without tweaks. I loved the sound from this setup, but I bought this system for sound and performance so Im a little pissed it didnt perform, making less than stock is unacceptable. Im glad you had good results with your setup.

Originally Posted by wrs

Yes but since I switched to the Cobb Tune I get to use the headers without the power loss and still have a custom tune. The AP is cheaper and more flexible than GIAC to boot.

Originally Posted by Tom@Champion

Have you dyno'ed your car with the headers, and without....keeping the tune constant? Just curious...

Originally Posted by sdg1871

This week, Champion Motorsports installed its new upgraded intercoolers and the GIAC Stage 2 plus tune to match it.

While I won't post the dyno graphs of my car until Champion formally releases its upgraded intercoolers with the GIAC stage 2+ tune I will share key facts. We also found out that the IPD Y pipe will not fit the Champion IC kit and that the FVD headers I was going to install in the car made it lose power according to the testing on Champion's dynojet dyno.

My car, which was the Europipe exhaust with 100 cell cats -- as opposed to Catless -- gained, in peak horsepower and torque, 30 wheel horsepower and 44 lbs ft of wheel torque on 93 octane pump gas. Had I used race gas such as MS109, it would have gain approximately an additional 25 wheel horsepower. But that alone does not tell the whole performance story.

Specifically, there are points in the rev range where the gap between the horsepower and torque produced by the new ICs and GIAC stage 2 plus tune and the GIAC stage 2 tune is as much as 50 wheel horsepower and 64 wheel torque in my car. That is huge. Also, as I had hoped for, the gap between the power produced by this new GIAC stage 2+ and the stage two is quite large at the higher RPMs. This is clearly, as GIAC promised, the Stage 2 plus tune not aggressively dialing back boost and timing and high rpm's as it does with the stage 2 tune and stock intercoolers to protect the intake air temperatures from getting too high.

Champion did not get a chance to test the Tubi catless race exhaust on my car versus my Europipe with high flow cats because they didn't have one in stock. That is a test I definitely want done.

As to whether my car's heat soak at events is gone I will take it to events and let you know what happens.

On pump gas of 93 octane, the Champion development 991 Turbo S, which has the Tubi catless race exhaust, produced about 10 more wheel horsepower and 35 lbs-ft more wheel torque than car which is equipped with the Europipe exhaust with 100 cell high flow cats. So it looks like the cats are costing 10 wheel horsepower and 35 lbs-ft of wheel torque but that is only an approximation because Champion did not dyno my car with the Tubi catless race exhaust because none where in stock.

While at Champion I rode (as a passenger) in a Tubi catless race exhaust equipped 991 Turbo S with these exact mods during its shakedown ride to ensure that the mods were functioning correctly. There is no question that the Europipe exhaust is quieter in terms of sound levels but still lets you hear turbo and wastegate noise and popping in sport and sport plus on letting off the gas. The Tubi catless race exhaust is much louder on cold start up and its popping/backfiring in sport and sport plus when you let off a hard throttle is significantly louder than Europipe.

The IPD Y pipe does not fit the Champion ICs unfortunately. We tried it in my car and the carbon tubes exiting the Champion ICs do not fit the IPD Y pipe. So my car did not get the IPD Y pipe installed. My car has the IPD plenum and that fits just fine.

I also had Champion install a set of FVD headers (I picked up these on my own used: Champion did not sell them) and dyno hem. Unfortunately they lost both power and torque relative to stock headers. And they lost large amounts of horsepower and torque at lower-midrange RPMs. Needless to say I am not using them and went back to stock headers. To me those headers do not work well with a GIAC tuned/Champion intercooled 991 Turbo S. I have no idea if they would work better in a car with different mods.

In terms of the number The FVD headers dropped from stock headers in both peak wheel horsepower and peak wheel torque -- drops of 7 wheel hp and 14 wheel torque. But the bigger story is that there are very large drops from stock in the lower part of the rev range. For example, at 3850 RPMs the FVD headers made 32 less wheel horsepower and 44 less wheel torque than the stock headers.

I will post the Dyno graph as soon as champion makes its formal release of its intercoolers with GIAC stage 2+. The reason is that the graph with the stock headers is my car is with the stage 2+ and the Champion intercoolers.

I am really glad I sent my car down to Champion Motorsports. They are among the best in the business in the Porsche world. If I were out west I would have used GMG Racing or HG Motorsports. If you want the most power it pays to work with a tuner rather than just an installer. Not only did they test the headers as I asked them to but they worked with GIAC to created a custom tuned version of the Stage 2 plus tune for my car which was the product of dyno testing and datalogging my car that produced one more wheel horsepower and 10 more lbs ft of wheel torque than the standard out of the box GIAC Stage 2 plus tune produced in my car.

So my conclusion is that the results were excellent but the real proof will come at events.

Originally Posted by Nfall

Finally made my decision because of you. Im ordering the intercoolers as a xmas gift for myself and best of all Victor is giving me the holiday discount. Cant wait to have them installed and tuned.

Originally Posted by sdg1871

Congratulations. It is a mega upgrade from stage two. The car really needs upgraded intercoolers to achieve its power potential and to make fast runs repeatable.

Champion has been making intercoolers for our cars for a very long time for quality. They have made a massive difference in my car. And of course you get the champion warranty is unmatched in the industry among Porsche turners.

Originally Posted by Nfall

Scott,

Thanks for all the info you provided. You are really a wonderful resource for us P car owners. Looking forward to doing some more events this upcoming year.
Happy Holidays.


P