hi i need some advice i have a b20 vtec with high compression pistons an ive been runing the car strong and its response perfect no promblem i recently replace the head an i checked my pistons an they move around when there in the motor is that normal the run strong someone told me there not suppose too move at all an said that i can blow my motor true or not

 

1st thing what is the set-up? Forged or cast pistons

2nd what is the piston to wall clearance? 4 mils for forged.

Finally, what do you mean by move around?

 

b20 block an b16 head 12.1 pistons egale rods and the clearance is stock 84mm an there forged pistons an when i mean move around u can move them side too side the pistons moves aoround in the cylinder

 

Check with your machinist to determine what he set your piston to wall clearance.

 

You can probably rock them a little. You could drop a bore gage in from the top and check the top portion of the cylinder, but if your compression is/was good then you're probably fine.