Thread: I feel kinda dumb for asking, buuut.....

I'm wanting to put together a high compression sr20ve with sr16ve pistons for daily driving. I asked my teacher (I'm in an automotive technology class) about using pistons from one block and putting them in another low milage block. He told me it'll be a ticking time-bomb. He said the shorter stroke of the 16ve is going to wear the pistons in a different spot than the longer stroke sr20ve. So when I go to put them in my block they'll have wear from the other motor plus the wear from my motor and it can cause the cylinders to egg-shape and it will wear the rings very quickly from loose tolerances. I'm kind of skeptical of this because I've seen it done so many times on these forums and they seem to run fine, as far as I know.

Here's what I'm thinking. The only part of the piston that contacts the cylinder wall is the skirts and the rings. The rings are going to be brand new, and the block I'm going to put these pistons in still has factory cross-hatching in the cylinders. I'll probably be using the 4cw crank and rods that came with this super low milage block, too. Seems to me like the rings would break in wonderfully and the skirts touching the cylinder wall should be fine and break in well because of the factory cross-hatching.

I want to know what you guys think. People on this forum seem to be correct quite often. Hopefully somebody with first-hand experience with this setup will chime in. Thanks.

Assuming sr16 and sr20 pistons have the same exact dimensions, would it matter?

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This is why you hone and true the cylinder walls, maybe get new rings on the pistons and make sure the piston you are putting in is true and not fudged. Of course these are my thoughts and I would do this before putting in new/used pistons.

its already been done... you over think thing ways too much just be about it dont talk about it

Thread moved to VVL.

The difference is in the crank, they're not the same stroke but they are the same bore.

He may thinks that the piston will sit in a different place

SR16 Pistons in an SR20VE will yield a ~13.5:1 Compression ratio, that's pretty high for a daily. But to answer your question, it has been done before. If you line hone the cylinders with a torque plate and get new rings, you shouldn't have any issue with "egging" the cylinders. You prbly don't even need to do that. =/

New sr16 pistons are cheap, buy them, peace of mind, profit.

I thought it was supposed to be ~12.5:1?


Good idea! Haha I never even thought of this. Would you happen to know how much they cost off the top of your head?