I'm going to change my exhaust while I have the tranny out and have easy access to everything. The kit I'm looking at starts at a 3 inch dp that expands to 3.5 and then 4 inches where it will replace the cat and then runs back and will dump out behind the wheel. Does this sound like a decent set-up (seems to sell a lot of 'em) and will it really give more HP like they claim (and maybe a little better mileage)?

Is there anything else to look at while I'm in there? I'm already replacing weak bolts at the manifold pipes and checking an exhaust leak around turbo inlet.

I've also read that there are some mods you need to do to the firewall. Any tips on that or should I just pound it out with a sledgehammer

 

Yes it will increase hp, and it definetly helps with spool up. What brand are you going with?<br>
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for the firewall i put the exhaust in and then took a piece of 1/4"x3/8" flat aluminum and stuck it between the pipe and the wall and hit it with a 4lb sledge. Did this a few times to make sure it was totally clear and that solved the problem. But there are many other ways.

 

Yeah on the firewall i just used a pry bar i love my new exaust much better and better sound!! Good luck with all

 

It's coming from Advanced Flow Engineering in Placentia, California. I found 'em on the web and he's on ebay too. Comes with a 2 piece downpipe and muffler. It's not stainless but hey, I'm self-underemployed so it's what I can do for now.

 

I'm thinking about wrapping the downpipe with 1/2 inch foil-faced ceramic wool insulation by the firewall just for extra protection. The stuff is used on chimney liners when we insulate them and it's good to 2100 degrees and zero clearance to combustible materials in that application.