1G pistons auto vs. manual?

[BADAZZGSX]

I took my 1G automatic shortblock to the machine shop today to have the pistons swapped over to 2Gs. I brought with me the auto pistons that are installed in the block already, some 1G manual pistons and rods, and my 2G pistons and rods. We got to looking at the rods and noticed that the recessed amount of dish in the 2G pistons and the 1G auto pistons were the same, then compared to the 1G manual pistons- both the 2Gs and the 1G autos had less dish recession proving the higher compression ratio theory of the 2Gs. But the 1G autos also? I decided to hold off on the machine work so I can check this out. Do the 1Gs have different pistons between the autos and manuals? Are the 1G auto pistons that are in my block the same as my 2Gs. Do they offer the same compression because they seem to have the same recession; or does the wrist pin ride in a different location in the 2Gs causing a higher compression. Any insight in this will help out tremendously. This is a pic of the 1G auto pistons in the block.

 

[BADAZZGSX]

And this is a pic of the sets I took with me. The piston on the left is a 1G manual and the one on the right is a 2G. You can clearly see the recessed dish that the pistons have and the difference between them. The pistons in the block appear to have the same amount of dish as the 2Gs. Any logical answers to this? All the pistons are stock DSM pistons, so I have no idea!

 

[BADAZZGSX]

Anybody have any ideas? Any suggestions? ANYTHING??????

 

[BADAZZGSX]

Can't anybody help!?! Does no one have any idea! What about the famed Wisemen or Moderators. I thought thats what they were here for? All I'm asking for is a little help! Not a KIDNEY!

 

[danthman3]

i never heard of any diff between auto and manual pistons
so im pretty certain all 1g's are 7.8:1