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2.25 or 2.5 inch piping? - 6G Celicas Forums

Topic #48463 15 posts Started by celitrd
alrite so in about a week i'm bouta do a custom catback with my muffler i bought [n1 style muffler] i dont know what piping to do either 2.25 or 2.5 because i heard if my piping is too big i will looose low end power so i'm wondering what is the piping on the greddy sp whats you guys results with a 2.25 and 2.5 piping results?
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QUOTE(celitrd @ May 22, 2007 - 7:00 PM) [snapback]560459[/snapback]
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alrite so in about a week i'm bouta do a custom catback with my muffler i bought [n1 style muffler] i dont know what piping to do either 2.25 or 2.5 because i heard if my piping is too big i will looose low end power so i'm wondering what is the piping on the greddy sp whats you guys results with a 2.25 and 2.5 piping results?



Is your car N/A? If it is, you'll need the smaller bore piping, 2.25" or so I'm told or you will lose power. If it's turbo'd, go for 2.5" or larger.

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2.25" will be best for you. If you have serious plans of swapping either 3S-GTE or 4A-ZGE I would say 2.5", but since it looks like you have some basic bolt-ons on the 7A-FE you should look into the 2.25".

1991 MR2 - T-tops - Crimson Red - Gen3 3SGTE - Lots of moneyI'm not really an asshole, but I play one on the internet.**** Photobucket
Yes 2.25

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On my GT I went with 2.5 inch and I love it.
GTs can do 2.5 no problem, but with an ST you don't want to go any larger than 2.25.
Seeing as alot of Alltracs go 2.5 it's a bit overkill for a 135hp car with very little benefit for the extra cost.

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I had about the same ? but I have a pretty stock GT for now but plan to go turbo, how would the car act if I put 3" from the header and did a Y past the rear with 2.25 duals? I just want to get the exhaust done for now but do not want to pay twice for it.
That'd be pretty pointless.

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im running 2.25 with a turbo and it works perfectly

BOOST GETS YOU LAID!!!!
Why would it be pointless? Turbos love 3" exhaust or are you talking about the Y, or the fact that duals look good. Do you think that I would loose power do to the 2.25 pipe after the Y, correct me if I am wrong but the two 2.25" = 4.5" which means more flow!
You'd be better off just doing 3'' all the way back. The chassis doesn't allow you to really do a Y pipe...one pipe makes almost a L turn, ruining any good flow.

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I see your point. I do all of my own work and my family owns a machine shop so the engine that is in the works will pust the limits of the 2.2 block. The engine will be far from stock as well as the turbo. I just know that I will need to get rid of all that extra exhaust.
yea dont bother y piping it into dual exhaust because your going to loose power because our engine dont put out enough air flow and i wouldnt do more than 2.5 unless you seriously planning on 300+ hp my suggestion would be find a shop that will do your entire exhaust i found one that custom made mine straight pipe the whole way back for 150 bucks

BOOST GETS YOU LAID!!!!
celitrd - where are you getting your exhaust done? I need to find a place in the area that can make me a 3" turbo-back.

94 GT - Sold -------- 69 Pontiac Lemans - Sold88 Alltrac - Sold ---- 04 WRX - Sold00 GT-S - Sold ------ 91 Miata - project/drift car95 GT - Sold -------- 96 GT - New Daily Drive