Dr Honda
Well-Known Member
An 800 quash gap should be at 1.2 to 1.6mm. That is an engine spec... and not a recommendation.
A lot of places will shave the head, to bring up the compression... but that's not the way to do it with a seadoo. The proper way is to cut the head... then, re-machine the squash band in the head. That way, you maintain the "Cooling" effect of the squash gap... but you make the main combustion chamber smaller. In turn, raising the compression.
If you have high compression now... it could be that someone cut the head... or it could be that the base gasket is the wrong size. I would check that now. If you are out of tolerance... and you put that pipe on... your top end will have a very short life.
A lot of places will shave the head, to bring up the compression... but that's not the way to do it with a seadoo. The proper way is to cut the head... then, re-machine the squash band in the head. That way, you maintain the "Cooling" effect of the squash gap... but you make the main combustion chamber smaller. In turn, raising the compression.
If you have high compression now... it could be that someone cut the head... or it could be that the base gasket is the wrong size. I would check that now. If you are out of tolerance... and you put that pipe on... your top end will have a very short life.