4" exhaust on 35rs?
Pressure loss is all that really matters. The benefit of the evo exhaust is that it can be very straight. The fewer the bends, the lower the pressure drop by a large margin. A good 3" with minimal bends and smooth transitions between flanges has no problem flowing a lot of air with minimal pressure drop.
A civic on the other hand that has multiple 90 degree bends to get around the rear axle benefits greatly from a 4" exhaust even at the 400HP level.
Now, if you were building an all out drag car, I would go with a 4" aluminum exhaust. You can make them very light and going to 4" reduces the heat transfer rate into the aluminum, lowering the operating temperature of the tube. Obviously operating temperature using aluminum on an exhaust is a bit of an issue but it works when done correctly for racing applications. The aluminum definitely makes the car sound like it has a tin can for a muffler, but if you like the sound of an N/A race engine at 10,000 RPM, you'll love the sound of 40+ psi on a 4" exhaust with a larger turbo and a good turbo manifold.
A civic on the other hand that has multiple 90 degree bends to get around the rear axle benefits greatly from a 4" exhaust even at the 400HP level.
Now, if you were building an all out drag car, I would go with a 4" aluminum exhaust. You can make them very light and going to 4" reduces the heat transfer rate into the aluminum, lowering the operating temperature of the tube. Obviously operating temperature using aluminum on an exhaust is a bit of an issue but it works when done correctly for racing applications. The aluminum definitely makes the car sound like it has a tin can for a muffler, but if you like the sound of an N/A race engine at 10,000 RPM, you'll love the sound of 40+ psi on a 4" exhaust with a larger turbo and a good turbo manifold.
Last edited by 03whitegsr; Feb 18, 2009 at 02:28 PM.
Pressure loss is all that really matters. The benefit of the evo exhaust is that it can be very straight. The fewer the bends, the lower the pressure drop by a large margin. A good 3" with minimal bends and smooth transitions between flanges has no problem flowing a lot of air with minimal pressure drop.
A civic on the other hand that has multiple 90 degree bends to get around the rear axle benefits greatly from a 4" exhaust even at the 400HP level.
Now, if you were building an all out drag car, I would go with a 4" aluminum exhaust. You can make them very light and going to 4" reduces the heat transfer rate into the aluminum, lowering the operating temperature of the tube. Obviously operating temperature using aluminum on an exhaust is a bit of an issue but it works when done correctly for racing applications. The aluminum definitely makes the car sound like it has a tin can for a muffler, but if you like the sound of an N/A race engine at 10,000 RPM, you'll love the sound of 40+ psi on a 4" exhaust with a larger turbo and a good turbo manifold.
A civic on the other hand that has multiple 90 degree bends to get around the rear axle benefits greatly from a 4" exhaust even at the 400HP level.
Now, if you were building an all out drag car, I would go with a 4" aluminum exhaust. You can make them very light and going to 4" reduces the heat transfer rate into the aluminum, lowering the operating temperature of the tube. Obviously operating temperature using aluminum on an exhaust is a bit of an issue but it works when done correctly for racing applications. The aluminum definitely makes the car sound like it has a tin can for a muffler, but if you like the sound of an N/A race engine at 10,000 RPM, you'll love the sound of 40+ psi on a 4" exhaust with a larger turbo and a good turbo manifold.
I agree on the use of a 4" exhaust. Al's car however has a 3.5" exhaust we built for him when it made the 1,000+ whp.
IF you feel you just have to have a 3.5" exhaust I have a turbo back I built for my RS. All 304 stainless, v-bands, Burns Stainless lightweight racing muffler, mandrel bent, I'd sell the entire system very cheap. The downpipe is set up for Vband to the turbo kit I built for my car. You will have to change your 02 housing outlet or change the top of the downpipe.
I'd sell the full turbo back like it is for $600 plus shipping. It is the LIGHTEST 3.5" system you are going to get for your EVO.
Honestly, a good 3" system is all you probably need though.
IF you feel you just have to have a 3.5" exhaust I have a turbo back I built for my RS. All 304 stainless, v-bands, Burns Stainless lightweight racing muffler, mandrel bent, I'd sell the entire system very cheap. The downpipe is set up for Vband to the turbo kit I built for my car. You will have to change your 02 housing outlet or change the top of the downpipe.
I'd sell the full turbo back like it is for $600 plus shipping. It is the LIGHTEST 3.5" system you are going to get for your EVO.
Honestly, a good 3" system is all you probably need though.
