hovel
ol' stupid
Not to hijack the intake tuning thread but Rusty reminds us of a very good point and I wonder if others have given this some thought. Look at the total length of the exhaust systems on the early XS. As years went on, the systems got shorter. We know that longer pipes produce more power than shorter pipes at low rpm's and vice versa for max rpm. Gary Hoos's street pipes are 42"-43"long and there is probably some science in that. Aside, I read some time ago that the ideal exhaust system was one single pipe per cylinder. This may have been written before we learned the benefits of proper length headers and correctly built collectors. My source may have been Phil Irving or maybe even Harry Ricardo - way too long ago. Look up "bundle of snakes".and provide sufficient backpressure at the exhaust (exhaust length is WAY more critical than intake length)