jimbo slice

Trying to figure out the deck height of a sleeved block. I have no previous history of this block, and I'm not even sure what kind of sleeves they are.

In any case it's an 85.5x87.2 all motor setup using

Weisco K594M855AP pistons set with a 1.181 comp height

Skunk2 Alpha rods measuring 5.433

When checking piston to deck I used a dial indicator and magnetic base and the "piston rocking" method. These are the measurments I came up with

.001 in the hole intake minimum
.013 in the hole intake maximum

.002 in the hole exhaust min
.018 in the hole exhaust max

I am Using the deck height equation of

(Stroke/2 + rod length + piston deck clearance + comp height )

I am unsure as to how I should enter piston to deck clearances. Do I average all four measurements or just the intake side? Do I assign the P2D a negative value for being in the hole?

And one last question, what is the definitive stock GSR deck height?

212mm or 212.39mm


My overall goal is to determine piston to head clearance. We want to safely rev to whatever DDTECH's single lobes stop making power at.

Natural Aspirations

Use the worst case number 0.001"

jimbo slice

Would I assign that .001 negative or positive, with it being in the hole?

Natural Aspirations

Negative. With that small of a number in this situation zero works fine. Did you check more than one cylinder?

It's going to be a good example of when you should bust out the silly putty (clay) and check clearances.

jimbo slice

I have only checked cylinder 1 at this point. I will check the other 3 today. I planned to clay the engine to double check my clearances.

Thanks for the help Natural.. Much appreciated.