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Thread: 2.25" exhaust
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Old 09-18-2012, 12:08 PM   #46
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Originally Posted by Sean05 View Post
Me too let me talk to them again and see if I can get any dynos or flow tests; but it makes sense because its smaller it doesn't have anywhere to go and keeps it more compact and hotter thus getting pushed out faster.
Edit: keep in mind borla and magnaflow test with stock headers so it may change if you add a header but one I add my Cosworth if
I chose to do so I'll dyno an see f I can crank out any more with a 2.25 exhaust.
I'm just veering away from custom and went with someone I knew fit. My 05 TruBendz was horible fitment problems till I fixed it. And it was a nightmare fixing them to the point after it was fixed I didn't want it anymore.
That would be great. That's a good point on the header as well.

That's sad to hear about TruBendz kit for the 05. Most guys I've heard using them haven't had such a bad experience. Hell, I'm hoping they or someone comes out with a stainless piping kit so I can change out the crappy stuff I have on now!

Originally Posted by dyn085 View Post
I would like to see dyno's showing a loss with a larger system. Typically, going larger will produce diminishing returns, but I can't imagine an actual loss, especially over stock.
That's what got me as well.

Originally Posted by TitaniumStick View Post
They were probably comparing it on a completely stock motor. I would venture to say that without airbox mods, the 2.5 killed too much backpressure and increased the pumping losses. You have seen that modding airflow makes the smaller exhaust a limiting factor, so going too large on the exhaust could make the smaller airflow a limiting factor. I have no doubt that the 2.5 produced more hp/tq vs. OEM, but it might not have outperformed the 2.25 vs. OEM
Good point.
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