wiseco piston ??

nightrider1 · 10-28-2009, 10:04 PM

Hello Bill my question is i have a seadoo with the 787 i have a set of new 83mm wiseco piston with (6) thousand's piston to wall clearence, what would be the clearence you would have done.these are like the stock piston not the flat top race pistons.what is your thoughts any will be a big help thanks again bill.

Bill O'Neal · 10-29-2009, 03:39 PM

If the engine is modified and you expect it to run hotter than normal, open up the clearances to between .0065 and .008.

nightrider1 · 10-29-2009, 06:48 PM

Bill here is my set up 1997 seadoo xp 787.the motor was just done buy Paul Lehr from ( LPW ) bored to 83mm +6 thousand's clearence,he said he did rec porting,new ada head with 39cc domes,Coffman brand new race pipe with ecwi, modified mikuni Buckshot 46mm carbs with matching Buckshot v tech intake manifold,hotrods crankshaft,stock pto flywheel,stock cranking flywheel,no total loss ignition,stock ignition using.the question is will it be okay to stay with the piston to wall clearence ( 6 thou ) and if not how long will the motor live with this clearence.Bill just to give you my riding characteristics i don't stay for long periods of time hard on the throttle, hope this can help with the answer. Thank's bill for any info.

nightrider1 · 10-29-2009, 07:56 PM

Hello Bill with the above post there is a 200 psi compression per cylinder with the ADA head 39cc domes.Thanks again Bill for the help.

Mr. Bill · 11-02-2009, 03:36 PM

200 PSI is definetly into racing gasoline territory and because of the extra compression, your pistons will run very hot. I do not suggest .006 clearances.