Super Jet Weird squish

[Waternut]

I just got my used Speedwerx motor yesterday and started doing some checking. The engine is a 771.

The engine has flat top pistons (kind of) and as best as I can measure, they have a 1.5° positive dome to them. Now the speedwerx head has 23cc domes in it and I measured a 24cc fill volume when installed. Now for the weird part... The squish band is approximately 0.560" and goes from 0.046" at the inboard side and 0.061" by the wall for a -1.5° squish. I always thought the squish was smallest by the wall. What would be the advantage or disadvantage of this?

 

[jetski9010]

maybe its something to do with keeping down the heat along the edges of the piston but I am just guessing.

 

[SUPERTUNE]

BAD!
Your feelings are right, this is squish setup is backwards.
When engines are setup this way on a o-ringed head the combustion chamber o-rings are toasted a lot!
It sounds to me that the head domes are machined for a Riva style piston ( a true 0* degree piston) and you have a Kawasaki domed piston that has a 2* degree piston top.

 

[Pablo]

You can find the Riva flat tops from Wiseco. I had to call them this past summer. Wiseco makes them for Riva. I couldn't get them through Riva.