how much gain

[redturboed95]

ive got a 95 gst running about 14psi wiht a cone filer and an opend up intercooler. i am having a 3 1/2" turbo back ut on any idea how much hp i'll gain or about what i'll be at.....oh yeah there willl be no cat

 

[kooka]

Somewhere between 200 and 400.

3.5" is big. whats the purpose?

 

[spinallfours97]

Depending on the condition the motor is currently in, i would say about 8 HP. A friend of mine just recently did the upgrade to a 3 1/2 with no cat. It achieved an extra 6 HP but his engine had about 149K on it... Good luck with the mods!

 

[alex99gst]

yes, seriously why would it be necessary to go 3.5" when theres people well in the 9's with only 3"?

it seems like a lot of people are asking if they can go 3.5" and get even more gains lately

 

[kooka]

it seems like a lot of people are asking if they can go 3.5" and get even more gains lately

overkilling progresses over the years.

 

[redturboed95]

no, its that the tuning shop where i order all my parts can make me a turbo back setup for $400 and i don't think its menderal bent so the make it out of 3 1/2" to comp.

 

[kerndog8]

a 2.5" with 14psi mandiral bent would be great

 

[ItsStockOfficer]

no, its that the tuning shop where i order all my parts can make me a turbo back setup for $400 and i don't think its menderal bent so the make it out of 3 1/2" to comp.

That won't compensate. Press bends kill exhaust velocity. Nevertheless, it will get the job done if you wanna be cheap. Power gains on T25's areminimal no matter what you do though.

 

[CanadianTSi]

Power gains on T25's areminimal no matter what you do though.

Indeed, going from stock exhaust to full 3" o2 elim. no cat, I picked up 0 MPH in the 1/4 but My ET went down...

 

[alex99gst]

no, its that the tuning shop where i order all my parts can make me a turbo back setup for $400 and i don't think its menderal bent so the make it out of 3 1/2" to comp.

i honestly dont believe that 3.5" press bent would compensate for that at all, like stated above press bent kills the velocity of exhaust gasses. press bends also create backpressure, which in turbo cars is the enemy, so why not save a couple hundred more and buy a quality 3" O2 eliminator turbo back from RNR? best choice IMO, that way if/when you upgrade your turbo no need to purchase a better flowing exhaust

 

[redturboed95]

can someone give me the web address roe RNR i'll give them a look till i can find out for sure how my shop bends the pipes .

 

[alex99gst]

www.rnrracing.com

i think this is what you are looking for

http://www.rnrracing.com/cgi-bin/cc...ef=fwdetbe1&cat=fwdtbe&catstr=HOME:DSM:fwdtbe

 

[myblack98gst]

sure go 3.5" but remember your exhaust will only flow as well as the smallest part... your turbine exit is slightly over 2" and the o2 housing exit is like 2 1/4" but hey its your money.

 

[kooka]

sure go 3.5" but remember your exhaust will only flow as well as the smallest part... your turbine exit is slightly over 2" and the o2 housing exit is like 2 1/4" but hey its your money.

so with that said we all should just run 2" exhausts.

 

[markgholland]

so with that said we all should just run 2" exhausts.

I think what he is saying that with a "smaller" turbo like the t-2-small(t25), 14b, 16G, etc., a 2.5" exhaust is all you need. A 3.5" exhaust is overkill in every way for his setup, and he will regret it later. I don't know about yours, but the "turbine exit" on my turbo is bigger than 2"
~Mark

 

[gsx91boy]

i honestly dont believe that 3.5" press bent would compensate for that at all, like stated above press bent kills the velocity of exhaust gasses. press bends also create backpressure, which in turbo cars is the enemy, so why not save a couple hundred more and buy a quality 3" O2 eliminator turbo back from RNR? best choice IMO, that way if/when you upgrade your turbo no need to purchase a better flowing exhaust

Shut the #### up. There's only slight bends in a dsm exhaust and the prescence of two pressbends isn't going to amount to shit in the grand scheme of things. If you're that worried just drop the exhaust @the downpipe @the track. With the money saved on a $200 home-brex exhaust vs. a $1000 shiny vendor exhaust you could be leaps ahead peformance-wise. FWIW I know of someone running 11.9@115 on a stock exhaust with an evo16g. Go back to reading Import Tuner until you have something valid to say.

-aaron

 

[x camaro owner]

That won't compensate. Press bends kill exhaust velocity. Nevertheless, it will get the job done if you wanna be cheap. Power gains on T25's areminimal no matter what you do though.

i don't believe this person under stood fluid dynamics in physics. otherwise he would reword what he says about what happens to the velocity of the gas when the diameter of a pipe shrinks.

 

[x camaro owner]

i honestly dont believe that 3.5" press bent would compensate for that at all, like stated above press bent kills the velocity of exhaust gasses. press bends also create backpressure, which in turbo cars is the enemy, so why not save a couple hundred more and buy a quality 3" O2 eliminator turbo back from RNR? best choice IMO, that way if/when you upgrade your turbo no need to purchase a better flowing exhaust

will some one pick of a physics book from college on fluid dynamics so they can under stand the difference between flow and pressure.

aaahhh screw it your just tool turning people, your not supposed to be that bright

 

[alex99gst]

Shut the #### up. There's only slight bends in a dsm exhaust and the prescence of two pressbends isn't going to amount to shit in the grand scheme of things. If you're that worried just drop the exhaust @the downpipe @the track. With the money saved on a $200 home-brex exhaust vs. a $1000 shiny vendor exhaust you could be leaps ahead peformance-wise. FWIW I know of someone running 11.9@115 on a stock exhaust with an evo16g. Go back to reading Import Tuner until you have something valid to say.

-aaron

like i said in what u quoted from me: i honestly dont believe that 3.5" press bent would compensate for that at all, like stated above press bent kills the velocity of exhaust gasses. press bends also create backpressure, which in turbo cars is the enemy, so why not save a couple hundred more and buy a quality 3" O2 eliminator turbo back from RNR? best choice IMO, that way if/when you upgrade your turbo no need to purchase a better flowing exhaust

I was just giving him my oppinion, so no im not gonna shut the **** up just because you dont agree with it. All I was saying was that a 3" mandrel bent exhaust flows better than 3.5" pressbent exhaust. If you want to go around flaming people when they give their oppinions after they are asked for this is the wrong board. :thumbdown

 

[gsx91boy]

like i said in what u quoted from me: i honestly dont believe that 3.5" press bent would compensate for that at all, like stated above press bent kills the velocity of exhaust gasses. press bends also create backpressure, which in turbo cars is the enemy, so why not save a couple hundred more and buy a quality 3" O2 eliminator turbo back from RNR? best choice IMO, that way if/when you upgrade your turbo no need to purchase a better flowing exhaust

You're just being redudant and illogical and modding like a person who wants to be stuck in the 14's, so please for everyone's sake STFU NOOB.

-aaron

 

[alex99gst]

I dont know what your problem is, but next time before you go flaming my posts I said that IMO and probably many other tuners oppinions that if/when you upgrade your turbo that 3" is the best way to go so that you dont regret it later. Thats fine if you disagree with me but you're the only one telling me to stfu. Im not gonna waste my time here listening to you whine about my illogical theory that mandrel bent is better than pressbent.

 

[burldude]

I know this guy locally that is running 4 inch in his wrx . Is it overkill "yeah" but I dont think he will ever have to worry about back pressure.

 

[x camaro owner]

application comes from theory and the way you people use common sense is the opposite of the real world explanation. takes some physics the world works completely differently than you think. application is no different than theory especially with car due to a very inefficient motor, vehicles aren't that hard to figure in theory. also for mr velocity guy the air speeds up through the press bend, but it does change direction so that would be a change in velocity but not the way you said it, you should have said man that press bent really makes the air change direction, its like whoa dude that air really has to move

either way it still has a 90degree bend

its flow man its flow that is your culprit