Is there a big diff. in flow of a 3" Ypipe and a 2.5"??
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Launching!
Joined: Jan 2002
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From: NY
Is there a big diff. in flow of a 3" Ypipe and a 2.5"?? I'm having a Stage II H/C done to my car in a few weeks. Over this summer I will be installing the Hooker LT's. Now I have the SLP 2.5" y-pipe now and was thinking of just having it bent and cut for the cats to fit the Hookers. So I guess my question is can I have the Slp ypipe fitted to the Hookers and if I could am I just better off selling it and having a custom 3" ypipe fabricated?
Thanks
Joe <img src="graemlins/burnout.gif" border="0" alt="[Burnout]" />
Thanks
Joe <img src="graemlins/burnout.gif" border="0" alt="[Burnout]" />
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From: Freeland, MD
Re: Is there a big diff. in flow of a 3" Ypipe and a 2.5"?? Here's my late-on-Saturday-night-because-I-do-not-have-my-car comment:
From the best I know, people have not seen much in the way of changes with stock cubed motors between the 2.5 and 3 inch y-pipes. I do not know whos it was, but I recall a dyno graph being shown before and after the y-pipe switch with no real differences. I do not know if the increased air-flow due to a really good head porting job would change that.
On the other had, there is apparently a huge difference between these for a larger cubed engine (383 or 42x displacement).
From the best I know, people have not seen much in the way of changes with stock cubed motors between the 2.5 and 3 inch y-pipes. I do not know whos it was, but I recall a dyno graph being shown before and after the y-pipe switch with no real differences. I do not know if the increased air-flow due to a really good head porting job would change that.
On the other had, there is apparently a huge difference between these for a larger cubed engine (383 or 42x displacement).
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From: Baton Rouge, LA
Re: Is there a big diff. in flow of a 3" Ypipe and a 2.5"?? I've switched between a g-hann 3 inch y-pipe, and a futral 2.5 inch y-pipe and saw no difference at the track. ALso, the g-hann y-pipe is one of the worst i've seen (along with the flp), and the futral y-pipe uses all mandrel bends and a flowmaster collector. The g-hann had no collector what so ever. But if I saw no differnece at the track it must not matter at my power levels. <img src="gr_stretch.gif" border="0">
How much power are you going to be pushing through this y-pipe?
How much power are you going to be pushing through this y-pipe?
Thread Starter
Launching!
Joined: Jan 2002
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From: NY
Re: Is there a big diff. in flow of a 3" Ypipe and a 2.5"?? I know that without the headers the car should be pushing like 370RWHP and with it should be up around 390RWHP. I think that I'm just gonna go with a custom 3" Y-pipe and just sell the SLP one. If I sell it would anyone be interested??? LOL.
Joe
Joe
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From: new england
Re: Is there a big diff. in flow of a 3" Ypipe and a 2.5"?? Shadow Z28, the power of your engine is dictated by the most restrictive part in your exhaust, if its not your 2.5" y-pipe than switching to 3" wont show power gains. Now this is a generalization and the exceptions go like this: the further you place cats or any other restriction away from engine the more power its capable of making. This area before restriction acts like a collector, the bigger this area is the less restriction hurts power. This is only worth some HP not a whole lot. By the way, this info is from DAVID VIZARD, the sharpest guy out there who is willing to share his knowledge, by writing books about it!
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From: Lincoln Park Mi
Re: Is there a big diff. in flow of a 3" Ypipe and a 2.5"?? dual 2.5 inch pipes flow more than a 3 inch, so if you are using 3 inch exaust 2.5 is fine, this is also a question I asked on here and at two performance exaust places, and everyone had the same answer, 2.5 is better.
a 2.5 inch Y will also give you increased low RPM torque, and will be a bit quieter (if you wnat that)
a 2.5 inch Y will also give you increased low RPM torque, and will be a bit quieter (if you wnat that)
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Verdad Gallardo TECH Regular
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From: Lincoln Park Mi
Re: Is there a big diff. in flow of a 3" Ypipe and a 2.5"?? Shadow, I saw your IM about an hour after you sent it, but you were already gone.
I paid 200 for it, would have been less if the collector had been made by the guy, but we went with a Flomaster collecor.
in the future if you IM me and i dont answer, just shoot an email, im probalby just not at the computer, i forget its on and walk away for hours sometimes
I paid 200 for it, would have been less if the collector had been made by the guy, but we went with a Flomaster collecor.
in the future if you IM me and i dont answer, just shoot an email, im probalby just not at the computer, i forget its on and walk away for hours sometimes
Thread Starter
Launching!
Joined: Jan 2002
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From: NY
Re: Is there a big diff. in flow of a 3" Ypipe and a 2.5"?? Freak it's ok I figured you weren't at the computer. Thanks for the info.
Joe <img src="graemlins/gr_hail.gif" border="0" alt="[hail]" />
Joe <img src="graemlins/gr_hail.gif" border="0" alt="[hail]" />
