Well, Milteck is the gold standard. I have has mine for over 10 years in the NE with no rusty welds or any other issues.
So in talking with a few folks, it appears the Milltek exhaust doesn't fit well on the GP2. Also putting it on and getting all the pieces correct is also an issue. Anyone have any experience with that? One person recommended this the Akrapovic.. its a bit more expensive though. https://www.outmotoring.com/akrapovic-evolution-exhaust-r56-8-s.html
Have you asked Chad? I am sure his guys know how to fit a Milltek correctly without any issues. Some times DIY’s do not give the best advice.
Yup talked with Chad and a few other shops. Milltek can be more cumbersome to mount and get fitted correctly. That said, the Akrapovic is also very nice, potentially a little lighter (need to confirm that) and the fit is spot on. It also comes with a set of very nice carbon fiber tips. Still working through the details between both of those. Now I'm thinking about my downpipe. I was thinking about having it ceramic coated. I do that when I put on headers for normally aspirated cars. It appears this is also pretty common and outside of just helping keep the engine bay cooler, it also increases the velocity high. Anyone here done that?
So been thinking about this more and doing more research about volume and velocity. What Turbo are you running and are you running a 3" downpipe or just a 3" exhaust?
GTX2860R with a catless downpipe from TurboKits who sold me the turbo in a kit. Married it to an Alta 3" exhaust system then added another resonator to keep noises to a minimum. After lotsa mods, this turbo is too small, so looking at another upgrade --- someday.
Oh snap - are you talking about this kit? https://www.atpturbo.com/mm5/merchant.mvc?Screen=PROD&Store_Code=tp&Product_Code=ATP-MCT-012&Category_Code=COOPER
Sure looks like it --- 3" all the way. Back in 2011, Turbo Kits got their materials from ATP Turbo. Also, my buy was before the GTX ~ it included a GT28RS. Current version is a much better turbo. Note --- their claim of 450HP must be in BHP, not WHP. Even the GTX can't provide the boost continuously thru the RPM max. Garrett catalog also limits HP claims to about 350 or so. Another thought --- when I had my extra resonator added, the shop mentioned they could have done the complete exhaust system for a lot less money than buying a bunch of fancy chromed pipes. Would have fit a lot better too. FYI --- there's a bracket / brace near the muffler that helps contain the system if supporting mechanism fails. This bracket / brace will not accommodate a 3" pipe and must be removed or have spacers added to longer bolts. Hasn't caused any problems in the 8+ years I've been without it. Actually easier to drop the exhaust when pulling the engine. Anyhow, you should consider letting a good, local, muffler shop build a system for you. If you're planning on a 300+WHP build, you should go with the least resistance muffler, and forget what it sounds like --- I can assure you it will be nice and deep sounding.
Good info.. I appreciate it. I was doing some more research. Based on the current Turbo I have in the car (Franken Turbo), it doesn't push nearly as much air. I also confirmed I already have a 2.5" catless downpipe.
Yup - AEM intake, strut brace.. and a very 16.4 pound exhaust. Trying to get the baseline Dyno run scheduled next week before I swap it all out.