do you agree with this? - Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum

BRSTYLE240SX · 08-10-2002, 08:49 AM

im thinking about how im gonna do my custom exhaust, there's a question about it on the tech chat, but nobody seemed to answer. But here's what i think. Instead of going 2.5 inches like most people do with NA setups, i think it would be better going 2 1/4 inches, so the air can keep its velocity, and have the piping then increase to 2 3/4. Because 2 1/4 will keep it going fast, and since hot air wants to go from compressed areas to less compressed areas, it will want to go into 2 3/4 quicker in order to expand!? Creating then some low end torque, because of the velocity, yet, not too expanded air in the 2 1/4, and creating high end torque as well, because once it expands, it can move quicker!

Does this make sense? or would 2 1/2 still be the best diameter for a NA 240SX custom exhaust?

08-10-2002, 08:49 AM	#1
BRSTYLE240SX Zilvia Member Join Date: Apr 2002 Posts: 229 Trader Rating: (0) Feedback Score: 0 reviews	im thinking about how im gonna do my custom exhaust, there's a question about it on the tech chat, but nobody seemed to answer. But here's what i think. Instead of going 2.5 inches like most people do with NA setups, i think it would be better going 2 1/4 inches, so the air can keep its velocity, and have the piping then increase to 2 3/4. Because 2 1/4 will keep it going fast, and since hot air wants to go from compressed areas to less compressed areas, it will want to go into 2 3/4 quicker in order to expand!? Creating then some low end torque, because of the velocity, yet, not too expanded air in the 2 1/4, and creating high end torque as well, because once it expands, it can move quicker! Does this make sense? or would 2 1/2 still be the best diameter for a NA 240SX custom exhaust? __________________ FS: 92 Coupe w/ AT and 118K miles, Red WB: 91-93 HB w/ MT and <140k miles, any color