Spec3VR6 said:
hks makes really nice exhausts. you will gain some power out of that. the more engine mods you have, the more beneficial upgrading the exhaust is
They make a wonderful quality exhaust. That said, you won't gain a bit of power on an SVT doing an exhaust until after you're FI.
Stock SVT = 58mm diameter
HKS SVT = 60mm diamter
The SVTF has a 2.283" exhaust bone-stock. The only real restriction there is the cat. The HKS is 2.362" diameter. Basically all of the other aftermarket exhausts for the SVT are 2.5" diameter (63.5mm). I'm not sure how much power you think you're going to gain by adding .021" when the exhaust is already not a restriction [???

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To my knowledge, there aren't even any dyno numbers available that show a significant power gain on the 2.5" exhausts on an SVT even with bolt-ons. I know at least one of the more prominent tuners started developing an exhaust for the SVT and then dropped it because they weren't getting any power worth doing out of it.
Same thing with the header.
At Sonic the other night we were driving each others' cars around. Mine has a FS Cool-Flo, tune, etc. with stock exhaust, the other two cars were 2.3 duratecs (one an ATX with FS stealth exhaust, the other a manual with the second gen. MBRP). Even with less displacement and a "stock" exhaust, mine sounded QUITE nice compared with the others. Anybody not knowing better would think the stock exhaust is aftermarket. [}

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Put your money to something that will make a difference - the stock SVT exhaust performs and sounds great [thumb]
Oh, and the last little bit that made me feel *very* good about my car. The two guys I was with both have significant driving experience with performance cars (for example, both have been trusted to drive the 300+whp FS duratec project car). Their response to driving my car was remarkably similar along the lines of "Wow! I forgot how nice a car the SVT is, your's really just wants to keep pulling and pulling!" [

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