custom exhaust ?

[proES03]

Can a custom exhaust with a 2.5''-3' pipe and like a Apex-i N-1 muffler give me the same hp gain and sound as a Aftermarket Cat-back like a skunk2? Do the aftermarket compaines use that much better materials than if I got it custom? I'm asking this because they don't make a full Apex-i N-1 cat-back for my 03 protege ES.:'(

 

[PaulMP3]

why such a large diameter? are you boosted?

 

[Striker187]

that's always been a question of mine. but i think you should still be fine cause the aftermarket companies still basically follow the stock path. they just make it in bigger piping. i'm going custom 3" aluminized steel (ss is too expensive) with mandrel bends.

 

[KYREDP5]

Make sure anything you get is mandrel bent. You don't want any crush bends.

 

[smithers_0990]

Are crush bends that bad if you dont have a turbo? It just seems like you wouldnt notice a diff.

Later

 

[Midnight22]

reduced diameter at the bends, which will slow down the exhaust gases, which is something u dont want when ur N/A and def dont want when ur turbo

 

[Striker187]

supposedly not much difference according to one muffler shop i talked to. maybe 1hp or so. but come on, there has to be a reason why all the top stuff is all mandrel bent....

 

[boostisgood]

The bends cause a ribbed inside of the tube. This will cause turbulance, and actually create a distored harmonics. This sound will also act as a backpressure source, along with the bends, and turbulance. You will actually see MORE loss with this then the stock system .

 

[proES03]

i don't know if i'm gona boost but just in case i do i don't want to have to mess with the exhaust.

 

[KYREDP5]

supposedly not much difference according to one muffler shop i talked to. maybe 1hp or so. but come on, there has to be a reason why all the top stuff is all mandrel bent....

I would guess the exhaust shop that was telling you that didn't have a mandrel bending machine.

 

[p5sundevil]

for N/A apps I would go no larger than 2.5-2.75", if u eventually plan turbo go with the 2.75, maybe 3" only if u are sure about the turbo.

If you are boosted the smallest dia. i would go with is the 2.75-3"

Also if u go that large on the exhaust it should be the same on your intake, should always be able to force as much air into your engine as can get out of it, and the other way around too.

 

[Striker187]

I would guess the exhaust shop that was telling you that didn't have a mandrel bending machine.

true true but then again, what muffler shop in their right mind would purchase one? btw...this shop also quoted me nearly $500 for my custom exhaust!!! wtf?? i found another place that'll do it for $225

 

[twizyours]

1/4 inch mandrel bent pipe is able to aoutflow 1/2 inch crush bent pipe because of the smooth flow pattern the crushes areas actually also have less diameter at the crushed bends. The crushed bent section will actually be smaller the the pipes diameter.

 

[proES03]

what kind of intakes would you suggest for a large intake? I was getting the AEM short ram. I really don't want to go with a CAI because of the whole taking in water issue.

 

[p5sundevil]

there is no taking in water issue, and if ur really worried u can get the AEM bypass valve. But in tests I have seen the filter needs to practically be submerged in water for a while for it to suck up detrimental amounts of water, plus most street CAI's dont hang low enough(or the car has a plastic flap below it like ours) so alot of water cant get up there.

For ones I would suggest, injen....I can get a GB price of 218 for 5 or more people but I have heard of deals from 213 to even 202 i think.

Other than that I really like my 40 dollar ebay intake with a raplcement filter, like K&N or HKS, I have a K&N style one that actually has the same material for filter instead of paper but I am lookin at an HKS style right now.

Other than that the ractive intake is almost the same as AEm but alot cheaper, um not sure who else makes em, I know HLS make a long CAI for ours cars that retails for like 5 or 6 hundred but there is one on ebay right now for 200.