Exhaust system

[hamtaro00]

peeps, just wondering why 4-2-1 for acceleration? because im thinking in high speed, those exhaust gasses no need cram into 4-1, when joining to 1 there will be alot gas turbulance that hamper gas going out fast. thus 4-2-1 better for hi speed? or was it a all rounder?

for my NA, i've only use 4-2-1 mainly because its mainstreat, or im misinformed, or its the right things to do. never tested aftermarket 4-1.

 

[jwalker86]

From what I've read in the internet so far, 4-2-1 & 4-1, does not make much of a difference. The part which makes it differentiate is the length of the pipe. The longer the pipe the peak power will shift to higher rpm range, the shorter the pipe the peak power will shift to lower rpm range. Length of the pipe is referred to the length starting from the header to the point where the pipes joints. Hence regardless what design everyone has they are actually similar. However this is just the summary of what I've read so far. The exhaust shops should be able to or have tested it to prove it right. Hopefully there will be some feedback on the above statement.

 

[hamtaro00]

jwalker, most of the medium range exhaust shop i visited have contradicting statement and not that high tech enough to do testing and letting end user understand it. the length of the runner did play its role as i've experience it.