ok, i searched and didnt come up with anything. which pistons do i want the a6 or the a1. they will be going into a z6 block. i am almost sure that it the a6 that are the flat and the a1 that are the domed but i am not completely sure. i was told that the one i want is a 10.5:1 piston in my engine.

 

There are two different D16A1 pistons, the 86-87 flat top and the 88-89 high domes.

I'll be back with some links for you.

BTW:

A6 pistons are a -3.4cc dish.

86-87 "PG6" pistons are like a +1.5cc dome while the 88-89 "P29" are a +7.2cc dome.

Here's a shot of my P29s:

 

Pistons specs:

http://www.muller.net/sonny/cr...t.gif

Put the specs in here to get CR:

http://www.c-speedracing.com/h...c.php

Best one though:

http://www.knology.net/~jediklc/D.htm

According to that last chart you'd want D16A6 pistons in order to get 10.4:1CR out of an otherwise stock D16Z6.

Why only 10.5:1CR though?

I run an 11:1CR D16A6 every day on pump gas with 22 degrees of timing (advanced) with no spark knock.

I'm sure I'll have to kick it back to 20 or so in the summer, but hell 18 is the dead center specs.

 

Those link are nice.