question about piston/block

[95tsiawd0330]

Is it possible to put ross .20 pistons in a block that maybe .30 or .40 over?

six months ago i bough a talon with a 6 bolt block with 7 bolt head and was having problems with oil getting on top of the pistons so i decided to take the motor apart and measure my ring gap and i got a mesurement of .37 i think the pistons are .20 over ross.so my friend has a block that is bored .20 and when i take one of my rings and measure the gap in his block it overlaps which makes me think that my block is .30 or .40 over. So is it possible to put .20 piston and install it in a .30 or .40 over block and be able to still run good and have compression of 170psi?

also what would be a good piston clearance measurement (piston to cylinder wall)??

EDIT: Today i went to the machine shop to find out what my bore is for my block and to see what size pistons i have and the guy at the shop said that my bore is .040 over and that my ross pistons are .030.after i was told that i called ross up and gave them the numbers under the pistons and ross said they are .040 over and when they left there place that they measured 3.381 from skirt to skirt now who is telling me the truth ????

1.) what is the measurment for a 6 bolt block to be .040 over
2.) and is a measurment of 3.381 is that a measurement for a .040 piston
3.) what are things that i need to know so i can order new piston and to get my block smoothed out ?

 

[arrowhead]

NO, but something is not right with your figures on your friends block.

 

[huafist]

3.381 is a .040" over piston ; a .040 bore is 3.386, so that gives you .005" ptw.