how to get 20 more whp???
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From: BR, La
Originally Posted by digndoug
I don't understand why you would want to go from 2.5 to 2.25? unless you are running an open muffler, or a fart can exhaust? If you run a real muffler, such as the Magnaflow setup I think you would want to stick to 2.5
How many people have tested this 2.25 vs 2.5?
How many people have tested this 2.25 vs 2.5?
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Originally Posted by Kris5597
Originally Posted by digndoug
I don't understand why you would want to go from 2.5 to 2.25? unless you are running an open muffler, or a fart can exhaust? If you run a real muffler, such as the Magnaflow setup I think you would want to stick to 2.5
How many people have tested this 2.25 vs 2.5?
How many people have tested this 2.25 vs 2.5?
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From: 203, CT
Originally Posted by digndoug
Originally Posted by Kris5597
Originally Posted by digndoug
I don't understand why you would want to go from 2.5 to 2.25? unless you are running an open muffler, or a fart can exhaust? If you run a real muffler, such as the Magnaflow setup I think you would want to stick to 2.5
How many people have tested this 2.25 vs 2.5?
How many people have tested this 2.25 vs 2.5?
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From: BR, La
nah dude it wasnt how it feels. it was car to car. my bud has I/H/E and he is running header back exhaust 2.5" with no cats and no resonators all 2.5" and a stage 3 performance cluthc. and im running I/H/E/P with factory s pipe and factory 2.25" midpipe with the 2nd cat still in with an added aero25 resonator and the factory resonator and we raced at a roll start at 20 mph and we both gunned it. he was by himself and i had a passenger and my driver side window down and i pulled ahead of him but not by much. after next light we ran again and this time i had my window up. left him behind from a 20 roll. now i do have a pulley but he does have a stage 3 clutch so i would think the clutch would be a lil better than the pulley and even with my factory s pipe and midpipe i still pulley ahead of him and i had more weight. now i cant think of anything that would cause me to pull ahead of him except for the exhaust. now im sure its not all the 2.5" im sure a lol of it was that he had no cats or resonators with a straight through muffler so there was no sort of back pressure but then again idk. i have more low end power than him and more high end. now a guy previously posted in this thread that he dynoed his car with 2.25" piping and 2.5" piping and he saw a 10whp drop with the 2.5" piping. now idk what else to say. i dont have dyno numbers no but just that race.
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From: BR, La
should couldnt be any worse than the s pipe thats already on the car. going from 2.5" to 2" to 2.25". very weird setup. all im saying is that with my car like it is its faster than my boys car with all his stuff done to it. i will be running megan header and 2.5" s pipe to 2.25 factory midpipe to tanabe concept g and it should have a decent bit of power.
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Kries Your basing this off you and your boy racing at a 20mph start? lol,
You will need some sort of back pressure. i can see no gain or loss of power by running say 3" w/o resenator or cat
2.5 with cat and resenator and muffler should be a perfect setup
I'll look into getting a dyno after i fix my setup
You will need some sort of back pressure. i can see no gain or loss of power by running say 3" w/o resenator or cat
2.5 with cat and resenator and muffler should be a perfect setup
I'll look into getting a dyno after i fix my setup
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From: BR, La
alright its whatever nothing to argue over ya know. dynos would be nice to see. and yes i was basing it off of that and what ive heard from others power gains and what not. but if anyone else has any input pls feel free to post. would be nice to settle this once and for all.
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Hmm now you guys got me wondering, I decided to keep my dc headers and picked up a 2.5" s-pipe I forgot whether its megan or invidia, and now I was going to have a custom midpipe made at an exhaust shop with a hi-flow cat, and a huge 30" resonator and I was going to make it 2.5" as well but I'm a little weary as to losing power from a lack of back pressure but if I didn't do 2.5 then the setup will b dc header, 2.5 s-pipe, 2.25 midpipe or 2.5 midpipe nd 2.5 axle back, idk what to do!
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i see you guys are basing this on N/A cars. i would have to agree with digndoug, on a n/a car that seems like the most logical power for all rpm ranges
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From: BR, La
idk maybe it is. make sure u have a high flow cat and at least one big resonator or two small ones. i mean i tested a straight through exhaust on my car tsudo header and s pipe with megan drift spec cat back and it was all 2.5" and i felt more power out of the factory midpipe than having the megan midpipe. lost some low end power and high end power with that setup seemed like i gained it back with the factory midpipe i have. idk i had only one resonator in with no cats so maybe that had something to do with it. all in all u want power out of your n/a put in a high flow cat. cats in the midpipe make a big dif with the aftermarket header. wheither its 2.25" or 2.5" piping your going to need to have a cat in for some sort of back pressure if not say goodbye to power cause its blowing straight out your exhaust. also the cat will help with the rasp. if u already have one or the other there is really no point in changing it. idk i guess the only thing to fix this dilemma is a dyno for each one. i think the 2.5" handles the rasp a lil better cause its a lil bigger but idk about any differences. either way piping runnign 2.5" all the way back or 2.5" into 2.25" isnt going to affect your power gains. if anything and i mean anything it might give you a lil more tq but just because of the tiny small lil restrictions at the flanges to where it changes.
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From: Orange County, CA
Originally Posted by jBoRiCuA
Originally Posted by digndoug
Originally Posted by Kris5597
Originally Posted by digndoug
I don't understand why you would want to go from 2.5 to 2.25? unless you are running an open muffler, or a fart can exhaust? If you run a real muffler, such as the Magnaflow setup I think you would want to stick to 2.5
How many people have tested this 2.25 vs 2.5?
How many people have tested this 2.25 vs 2.5?
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From: BR, La
no im talking about the whole exhaust system. running dif sized pipes with turbo will def cause u to lose hp with turbo. you said running 2.5" piping with turbo is bad im saying thats not true. that i know plenty of ppl running 2.5" straight through turbo back exhaust. now u might get more hp out of a 3" but you can run 2.5"
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Re: how to get 20 more whp???
Originally Posted by IcetC
alright guys here goes, i went and had my car dynoed in like march and at that time i had Injen SRI, DC 4-2-1 headers, AERO 14" resonator (not really for power but it effects exhaust flow) and trd exhaust and i dynoed at 160 whp and 161tq which i thought was pretty good, i have a solid torque curve from 2500 all the way up, but i'm looking for a little more pep so i converted from SRI to CAI and got rid of the trd exhaust and picked up a greddy evo 2. haven't been dynoed since but i can feel its a little stronger not by much though, so i'm looking to upgrade, so what should i do? heres what i was thinking
getting rid of my dc sports headers and trying to get my hands on a set of MMW headers and s-pipe because from what i read those will get me the most power
either buying or having a custom made 2.5" midpipe made at an exhaust shop
and adding a water/meth injection to my car either devils own, snow performance or the AEM one
i'm looking for around 180whp because then i'm cutting into SI and type S territory i'm not looking for crazy speed but enough to hold my own and pull a nice 1/4 time
i know this can be done to get to 180whp, because a friend of mine had a tc with injen cai, i think he either had MMW headers or Alphawerks, or are they the same? and a full 2.5" magnaflow exhaust and he dynoed at 179whp, he still has the dyno sheet and i'm working on getting it so i can scan it
also i dont want to be too loud but it basically goes the louder you are the more power...well sometimes...so can anyone think if how i should have the mid-pipe built after the s-pipe to still make power and keep the noise down? thanks guys!!!
getting rid of my dc sports headers and trying to get my hands on a set of MMW headers and s-pipe because from what i read those will get me the most power
either buying or having a custom made 2.5" midpipe made at an exhaust shop
and adding a water/meth injection to my car either devils own, snow performance or the AEM one
i'm looking for around 180whp because then i'm cutting into SI and type S territory i'm not looking for crazy speed but enough to hold my own and pull a nice 1/4 time
i know this can be done to get to 180whp, because a friend of mine had a tc with injen cai, i think he either had MMW headers or Alphawerks, or are they the same? and a full 2.5" magnaflow exhaust and he dynoed at 179whp, he still has the dyno sheet and i'm working on getting it so i can scan it
also i dont want to be too loud but it basically goes the louder you are the more power...well sometimes...so can anyone think if how i should have the mid-pipe built after the s-pipe to still make power and keep the noise down? thanks guys!!!
