Ok so I bought SRP pistons for my D16z6 but when i lookied up a part # on the box, pistons actualy turned out to be for a D152/B7 so now the question is can i still use them? and if yes what would be the difference? bore size is the same so the only difference is compression? but how do I calculate the compression? here are the specs on both sets of pistons...

I originaly thought i was buying these:




But got these:

 

the d16z6 is a p28 and the b2 has a pm6 piston, the compression calculator i use says the D15b7 piston is a pm3. The p28 piston has more of a dish than the pm6 piston which is more flat in comparison... cant say much about the pin differences though.
anyways PM3 pistons in a D16Z6 will produce a 11.26 compression ratio. An a6 pm3 -3.40 dome displacement (like the ones you have) will produce 10.432 compression ratio.

Idunno then again the rod and stroke are different between the two applications. ...I tried calculating it in with the stroke and different rod lengths and i got a 7.32 compression ratio.

 

You have to calculate the compression by entering the dome CC's in to the calculator. I already did it for you

This is assuming that its a stock D16Z6 with stock head gasket thickness.

Part # 149199 will give about 9.05:1 CR

Part # 149184 will give about 10.43:1

Now with a 0.40 head gasket as that is what they base their CR on.

Part # 149199 will give about 9.0:1 CR

Part # 149184 will give about 10.36:1

So yeah, you could return them or another option is to run a D16Y8 head which will give you around 9.6:1 CR.

 

yeah i used the compression calculator and got the same results but thought that maybe there was something else that i overlooked... something like a pin location on the piston that could realy change the compression #

 

Pin location and dome but you cant really change that.

 

I know the main diff in 75mm engines is the newer ones usually have a different deck heght, and most of the 95- motors are based on zero deck height. You should check to see if the different motors have the same pin-deck height, as that will change compression a bit.