While I have my engine completely apart I thought I would buy some higher compression pistons since the Mrs. won't let me go turbo. I was just going to buy some 10:1 pistons from nismoparts.com but they have different grades. (Grade 1, Grade 2, Grade 3) I know Grade 8 is stong for bolts, but I am kind of confused on this piston grade thing. All the different piston grades were the same price, so that threw out my idea of "The most expensive must be the strongest". Please help me out and clairify this a little bit for me.

Thanks

Dan,

Each piston grade is a slightly different size. Pistons in the SR20 are matched to their individual bores. Have you got the head off the engine??? If you do, there will be a single digit number stamped beside each cylinder 1, 2, or 3. sometimes if the piston heads are clean enough you can see the stamped number on these as well. you will need to order the grade that corresponds to that cylinder. Sometimes they are all the same, sometimes they are all mixed up. If you are not boring the cylinders at all, the STANDARD piston ring set will work fine for all the different grade pistons. Just make sure you check your ring gap when installing them.

OH! So that is what those number 2's next to the cylinder bore mean! Thanks alot. (I feel like a dummy now) :D

you're welcome