800 big bore piston

I have a M7 with 800cc.
The pistons are wiseco pistons from Black magic.
Nr 9954M 85.00mm.

Now it´s time to change the pistons but where can I find them.

I don´t think I can use polaris 800 pistons.
Maybe AC 800 OEM?

Looks like you might be able to use the M8 pistons (85 mm bore X 70 mm stroke). Give wiseco a call or call SPI.

NSC

I have a kit that I used stock cat pistons 800cc

But I´m not sure 800 oem piston will fit my cylinder and top.
Isn´t 800 oem piston higher?

Or have anybody switched from wiseco to oem?

BigRiver said:

But I´m not sure 800 oem piston will fit my cylinder and top.
Isn´t 800 oem piston higher?

Or have anybody switched from wiseco to oem?

Click to expand...

Lots of people have switched from wiseco to OEM and back and forth. If the cylinder was just bored out and not decked or dropped (thinner base gasket) or it does not have an aftermarket head on it, in theory a stock bore (85mm)800 piston should just drop in (Wiseco makes replacement pistons for stock sleds - there is no difference between the pistons, well there is but not size wise). Wiseco lists a stock 800 piston with a 85 mm bore for the 70 mm stroke on the 800 motor. Your stock stroke should have been 70 mm. Unless the piston pin height is different from the 800 to the 700, the 800 piston should fit if everything else is the same.

You should be able to use stock OEM pistons or Wiseco's. The pistons from Arctic Cat and Wiseco will be the same bore. You need to measure the cylinder and see what bore you have, then go from there.

NSC

You do have decked cylinders for the wiseco pistons and will need to raise them for the oem pistons. Eric at the racinstation has a kit that will do this so you can use stock m8 pistons.

Pm racinstation on here.

MX

Thanks for the answers.
The cylinders are not decked, just bored out.
I did the job by myself -04 from F7 -03 cylinders.
85.00 bore and ported for turbo.

Time for new pistons, 5 seasons and lots of miles.

I will try oem pistons.