3" hurt perforance?

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Dec 2, 2009 | 01:40 AM

#51

revolution607@yahoo.

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From: El Paso, Texas

Quote:

Originally Posted by EXsoccer1921

you're always reading my mind. haha

intake, HAHN header, HAHN dp, HAHN catback, 2.8/60, methanol.

fixed it for ya bro!

Dec 2, 2009 | 01:42 AM

#52

EXsoccer1921

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From: The 405

well i figured i would leave those out in this thread. since people say 3" hurt performance till 300hp

Dec 2, 2009 | 01:44 AM

#53

revolution607@yahoo.

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From: El Paso, Texas

Quote:

Originally Posted by EXsoccer1921

well i figured i would leave those out in this thread. since people say 3" hurt performance till 300hp

has anyone ever proved that? like with dyno numbers or something...

Dec 2, 2009 | 01:54 AM

#54

EXsoccer1921

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From: The 405

not really. but i did do 231whp 205wtrq with an ebay muffler and 2.5" crushbent axle back

but then i also did 250wtrq with a 3" lol

Last edited by EXsoccer1921; Dec 2, 2009 at 01:54 AM. Reason: Automerged Doublepost

Dec 2, 2009 | 01:56 AM

#55

revolution607@yahoo.

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From: El Paso, Texas

Quote:

Originally Posted by EXsoccer1921

not really. but i did do 231whp 205wtrq with an ebay muffler and 2.5" crushbent axle back

but then i also did 250wtrq with a 3" lol

just a 3" or was it with your ottp kit also?

Dec 2, 2009 | 01:59 AM

#56

EXsoccer1921

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From: The 405

i don't have an ottp kit. and it was with the mods i posted in here

Dec 2, 2009 | 02:02 AM

#57

revolution607@yahoo.

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From: El Paso, Texas

Quote:

Originally Posted by EXsoccer1921

i don't have an ottp kit. and it was with the mods i posted in here

ah! i thought you got a ottp stage 1 kit...

Dec 2, 2009 | 02:18 AM

#58

EXsoccer1921

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From: The 405

nope. i was running around with just the muffler. then i got a ticket and was completely stock again. then got a 2.8/60s and a tune. then added the exhaust, intake, and h/e over a couple months. then the methanol and retune

Dec 2, 2009 | 07:46 PM

#59

Omega_5

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From: Maidstone, SK

Quote:

Originally Posted by rukkee

When i had my SS/SC i swapped catbacks with the GMPP exhaust . When i was measuring the stock exhaust I found that the stock resonator had a 2 and 1/16th inch inside diameter right behind the flange that connects it to the downpipe . It was 2- 1/16th'' for a short run of maybe 2 to 3 inches and then opened up into the resonator. I'm wondering if since the restriction is only for a short run in the pipe does it kill flow the same as if the whole catback was 2 and 1/16th........or if by opening up again it helps with velocity or some other aspect O'm not aware of?

I'm guessing that restriction in the stock res is why people saw gains with the "smaller" than stock....2.25" GMPP exhaust's . I'm no expert when it comes to exhaust's so this is just me thinking out loud. Please feel free to correct me if i;m wrong.

The neck down does affect how the exhaust performs... but it's not as big of a deal as some people think.

To put the stock catback into perspective... on a 260-ish car, going from a magnaflow back to the stocker only lost about 2HP, and needed pretty much zero changes to the tune. No knock, and the trims went a 0.5 rich.
However, changing out the header back to stock, lost a lot of power.... very noticeable in the mid-top end.