Originally posted by tennessee
Why not just have a pipe for long tracks and a pipe for short tracks
Most pipes are 1 piece these days spcificaly designed for long and short tracks
If you need more bottom end you might be able to fix that by adjusting you're clutch, top end change gears
Depending on what motor you run can have an effect on you're pipe choice also
Also engine tuning plays a big part
But hey if you want to goto the track and hack on a header while everyone else is running they're car then have at it
I've had a pair of pipes and manifolds before at the track. However, since I race on only one track, it was just 'testing' to see which suited my purposes best.
Also, the length of the pipe/manifold combo is like adjust the midrange needle on a carb, however, it is easier to do. It doesn't do much, but its something to exploit if you have the time. It doesn't affect the car when it first engages the clutch, but it slightly affects acceleration from corners (or however you want it to affect your car).
The advantage between a pretty good length and the perfect length is very minimal, but certain manifolds are plainly too long, and so you have to alter the length in order to have a combo that is 'pretty good'. With one piece pipes, though, they are already 'pretty good' (or quite possibly 'very good') in the respect of their total length.
The reason I stick with two piece exhausts as opposed to one piece units is that I am more comfortable and acclimated to them. I always fear a one piece will pop apart (even though I know it is very unlikely). I feel safer with my 5mm thick coupler and hoseclamps keeping my exhaust system together, then with three springs keeping a onepiece together.