Welcome to the site! >

> Sorry about those immature sarcastic posts from a couple members(If you saw them...I removed them.)
Anyway, you could make a custom intake for your car for probably $50-70 in materials. There's a how-to article about how to do this in the how-to articles section of the site.
Also, you could get a custom exhaust system made for under $300 I'd imagine. I got mine made for a total of $150 or so...it's crush bent, which isn't as good as mandrel-bent, but it's still better than stock. >

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I've heard good things about underdrive pulleys for our cars as well. I think Unorthodox Racing makes one for the GT. You'd probably wanna do some more research on this one though...I don't know much about it.
You could modify a header to work for your car for under $300 I think, but it wouldn't be much of a gain.
There are a few ideas for you. >

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