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hpro123 · Dec 13th, 2002, 08:02 AM

You are kidding, right???

The less backpressure there is, the most HP you will get. If you can get it down to 2-2.5psi you are close to ideal.

However, note that pressure is NOT the only parameter you have to consider. Pipe diameter is also critical since it is the diameter of and the smoothness of the pipe that mainly (combined with backpressure) dictates how effective the exhaust is.

The exhaust needs to be of a diameter that allows the exhaust gasses to travel at the maximum speed attainable while having the least backpressure. Hence, you cannot go too wide a pipe since it will drop the exhaust gas speed and result in loss of torque in all the revving range except maybe the very top.

I am not familiar with GA16 engine requirements but for a n/a with less than 2 liters do not go over 2" in diameter. For the SR20DE, 2" up to 2.25" is fine.

Again, backpressure? 2psi is better than 2.5psi and 1.5psi is better than 2psi.

I doubt that you could ever insert any permanent pressure gauge there since you would need to measure pressure at 2 point along the exhaust (so 2 sensors and 2 gauges) and I do not know of any "differential" gauge that takes input from 2 sensors.

Chris

Dec 13th, 2002, 08:02 AM	#3 (permalink)
hpro123 Nissan Enthusiast Join Date: Apr 2002 Location: Athens, GREECE Posts: 126	You are kidding, right??? The less backpressure there is, the most HP you will get. If you can get it down to 2-2.5psi you are close to ideal. However, note that pressure is NOT the only parameter you have to consider. Pipe diameter is also critical since it is the diameter of and the smoothness of the pipe that mainly (combined with backpressure) dictates how effective the exhaust is. The exhaust needs to be of a diameter that allows the exhaust gasses to travel at the maximum speed attainable while having the least backpressure. Hence, you cannot go too wide a pipe since it will drop the exhaust gas speed and result in loss of torque in all the revving range except maybe the very top. I am not familiar with GA16 engine requirements but for a n/a with less than 2 liters do not go over 2" in diameter. For the SR20DE, 2" up to 2.25" is fine. Again, backpressure? 2psi is better than 2.5psi and 1.5psi is better than 2psi. I doubt that you could ever insert any permanent pressure gauge there since you would need to measure pressure at 2 point along the exhaust (so 2 sensors and 2 gauges) and I do not know of any "differential" gauge that takes input from 2 sensors. Chris Last edited by hpro123 : Dec 13th, 2002 at 08:32 AM.