7afe Piston sizes Options

[whirledpeaz]

I'm just starting to tear down a spare 7afe for my celica. I don't know if I will need pistons or other machine work yet as the engine has >250K on it. I read Smaay's excellent rebuild thread but I still have a question. With aftermarket pistons I see either STD or oversize. I don't see them broken down into 3 std sizes like oe pistons. Why is that? Is it a "close enough" kind of thing? If I need a piston I'll most likely get an oe toyota one but I was curious on this.

[Smaay]

when you go OS, the bore is machined to match the piston. OEM has various sizes because of mass production.

I highly suggest getting the oversized pistons and have the block machined. the 7A responds very well to this upgrade. In fact the engine in the build thread is for sale now.

[whirledpeaz]

when you go OS, the bore is machined to match the piston. OEM has various sizes because of mass production.

I highly suggest getting the oversized pistons and have the block machined. the 7A responds very well to this upgrade. In fact the engine in the build thread is for sale now.

Thanks for your replay. I understand what you're saying, let me rephrase my question. With an aftermarket std piston how would you know which oem bore size(1,2 or 3) it would fit? There's .004" difference between sizes according to the bgb. On the engine for sale, where and how much?

Thanks,

This post has been edited by whirledpeaz: Nov 18, 2013 - 1:03 PM