Downpipe / Catback questions

[j_eclipse96]

When I bought my car, the guy I purchased it from had a 3" downpipe that he was planning to put on. He gave it to me, and now I am debating if I should use it or not. I am still on the t25, but am planning to upgrade to a 14b with a full exhaust as soon as possible.

I was reading, and got the impression that a smaller turbo like a 14b on a full 3" exhaust would creep, even if the turbo, o2 housing, and manifold was ported. Is this true? And if it is, could it be solved by running a 2 1/2" catback instead of a 3" system, or should I sell the 3" DP and go with a full 2 1/2" system? Thanks.

P.S. My goals with the car are to stick with the 14b for awhile, and I'm not intending on upgrading the fuel system beyond a 190 for now.

 

[DGajre777]

You need to decide what your final turbo will be. There is no sense is getting something now and upgrading your exhaust later.

Yes, 14bs and even Evo III 16Gs will most possibly give you boost creep on a true 3" exhaust. Putting a smaller exhaust to prevent boost creep is an ass backwards way of going it. The proper way to fix boost creep is to port your turbo or go to an external wastegate.

I'm running a 3" Apexi N1 catback and plan to go with RRE's downpipe (www.roadraceengineering.com) which is 2 1/2" before the flex and then go up to 3" after the flex. Check the parts catalog for a complete list of exhaust systems.

 

[DAmotorsports]

Trust us you will want the 3inch in the future.