so after rigging my sachs 505 1a exhaust with a new spring mount. i noticed when the back pressure was high enough the pipe would slip off the header enough to eleviate the back pressure and i got a performance boost of like 7 mph. when the back pressure was low, it would slip back on, due to the spring tension on the expansion chambers clamp.
is there a standard back pressure or rather a recomended minimium? if you can put a tiny spring loaded valve on a pipe, would this translate to a boost across the board keeping the back pressure at optimium levels?