did a search...Who makes the largest exhaust piping?

[SR PwrdVA]

Apexi GT was the largest I could find at 3.75. I'm going to be pushing around 450...500on the bottle soon and was considering getting a larger exhaust after I rebuild my head. Is the GT the largest manufactured?

[Coolwhip]

yes, i believe APexi is the only manu. out of Japan with a pipe bender for that large enough pipping

[TruboostPerformance]

If your going to pushing alot of hp a custom one is the best way to go, and saves money also, just takes some time

[Goose93]

You need to look at flow numbers and some test results. A smaller tuned exhaust will produce more power. Depending on where you want the power to be can change how the exhaust is shaped.

A good header and highflow cat will mean more to you than size of final piping. If you remove to much back pressure you can lose overall power and low rev drivability can suffer.

[USDMSTALKER]

http://www.raretrick.com/index...=5407

[Hijacker]

You need to look at flow numbers and some test results. A smaller tuned exhaust will produce more power. Depending on where you want the power to be can change how the exhaust is shaped.

A good header and highflow cat will mean more to you than size of final piping. If you remove to much back pressure you can lose overall power and low rev drivability can suffer.

on an N/A car, yes. But these are turbo cars.

backpressure is never ideal, but the big concern when it comes to exhuast diameter is not how much back pressure does it create, but how does it effect exhaust gas velocity. If he opens the pipe too much, he loses velocity of gasses, and therefore the pressure after the turbo will not be able to drop as rapidly, resulting in a slower spooling turbo.

the best idea for what you want is to with a custom application. I would personally stick with a 3" pipe as it has been proven to be the best sized pipe for our engine setups. Even with nitrous, i don't see the need for a bigger pipe. What I would do is have it be a side exit pipe with no restrictions. No cat and no muffler. The car WILL be loud this way, and I would be weary of driving it on the street, especially if it were throwing flames between shifts. Also, the police frown on unrestricted exhausts, and I've always believed that a fast car should be a subtle one that doesn't draw attention to itself. But to each their own.

[Goose93]

Diameter is not the only part of the solution. This is where tuning the exhaust comes in to play.

[B.L]

Dont hks have a 4" exhaust.

bit pricey though....

[Nurv]

Apexi GT was the largest I could find at 3.75. I'm going to be pushing around 450...500on the bottle soon and was considering getting a larger exhaust after I rebuild my head. Is the GT the largest manufactured?

On the S13/S14, that might be the biggest availible. Now im gonna be the *** that says that using piping like that would be a bad idea. If you have a drag car with 272 or above lift cams, etc.. then this would be ideal. 500hp is alot. You get alot of flow with this size but alot depends to on the flow numbers. Alot of people go with the Blitz Nur Spec since its 80mm size and canister provide great numbers. As well I would suggest the Greddy Titanium 800 Race Exhaust. No resonator, no stainless crap, just plain coated titanium. Alot lighter weight and gives true bolt on performance.

Bigger isnt always better. I think in the land of the rising sun, Trust and HKS offer bigger than this but keep in mind you are looking at racing exhaust, not race style exhaust. Now if we were talking GTR's and the RB26 then 95mm piping isnt such a rare occurance.

[compression]

My friends H22 civic has a T78 turbo (its a drag car) that is making simila Hp numbers (500 or so). He is using a 3.5" exhaust that he custom made. He had to go to the diesel industry to get the mandrel bends he needed in 3.5".Generally speaking, bigger is better. The lower the back pressure the better turbo performance you will get. Read Mike Kojima's book "Honda and Acura Performance". there is a lot of good information that can be applied to non-honduh applications.Anyway, I think that anything over 3.5 is overkill, so I would keep it under that. You also dont have a ton of room for an exhaust that big unless you dump it out the side.Normally aspirated motors are a whole different story, but they suck so we wont talk about them.