[Gearz]

Do we know which downpipes meet the requirements for the SCCA STU class?

The rules don't allow a CEL defeat by the ECU (14.10), but do allow aftermarket catalytic converts in the original location (14.10.E), headers may be added, heat shields may be modified and the O2 sensor may be relocated on the header (14.10.D).

I don't want this to turn into a rules discussion, there are plenty of threads on other forums for that. Rather, I'd really like to know if there are any turbo-back systems that won't throw a CEL light - for the '08.

Thanks,
-Brian Meyer

[kts262]

There was a clarification about a year ago for ST* and exhausts. Check the NASIOC Motorsports section for more info, but basically you can't have *ANY* type of defeat, electrical, mechnical, or ECU.

Right now most of the exhausts out there look like they might still throw a CEL. I know with the GDB a lot of people have had luck with the Perrin setup that still has 2 cats, or they have gone the custom route. I'm not sure if Perrin has a downpipe for the 08 out yet but that is probably what I will go for if I decide to get a downpipe.

Cobb and APS will probably also be options that might not throw a CEL but they aren't out yet. You may want to wait a few months for more options to be available before you get a downpipe.

The header part you quoted doesn't apply to this since the header on the STi is preturbo while the downpipe is post turbo.

There is also the huge cluster-f about what "emissions compliant" means when it comes to the exhaust now and it's still a mess. There were no protests at the 2007 Nationals so for now it's still a gray area.

[spongebobnopants]

Originally Posted by kts262

I'm not sure if Perrin has a downpipe for the 08 out yet but that is probably what I will go for if I decide to get a downpipe.

They have one for the '08, and I was told by Perrin it would not throw a readiness cell on a stock tune, but I never tried it since I got it to run a stage 2 tune. They do however have issues with getting the right products in the right box. And the pictures on their website are a crap shoot.

[waktasz]

Originally Posted by spongebobnopants

They do however have issues with getting the right products in the right box. And the pictures on their website are a crap shoot.

True dat!! It was a PITA trying to figure out which front swaybar would work, and which wouldn't. Their website conflicted with the person at Perrin who I talked to which conflicted with all of the vendor listings I had seen at the time.