Is the location of the new X within an inch of where the Y used to be?
Have had issues with altering the effective lengths of runners myself, usually easiest to try and keep it the same unless you have infinite fuel tuning capabilities.
If you've noticed, the S&S headers do this, both for fitment to several years/models, and presumably, for tuning reasons.
Have had issues with altering the effective lengths of runners myself, usually easiest to try and keep it the same unless you have infinite fuel tuning capabilities.
If you've noticed, the S&S headers do this, both for fitment to several years/models, and presumably, for tuning reasons.