7MGTE sleaving the block? Toyota oversizes pistons

[bobtsgt]

I just recently found out that my 2 of my cylinders have some good scratches in them. I was wondering if it is safe to sleave the block inorder to use my stock pistons? I don't know if these motors respond well to sleaving or not. And if sleaving is not an option, I can get oversized pistons from Toyota. They are half a mm bigger then stock. Does anybody know what size this means in overboar sizes. Like 20 or 40 over. Any help will be appreciated. Thanks.

Bobby

 

[Bishop92t]

Toyota makes standard and 20 over pistons (the ones you are referring to). I've also seen some aftermarket piston companies making as large as 40 over. Personally I wouldn't sleave the block.

 

[bobtsgt]

Thank you so much Bishop. I have been asking many people about the size and you are the first to give me a straight answer. I shall get the 20 over then. I can get them for $320 for all 6. Woop woop. Thanks again.

 

[IJ.]

I'm with Bishop on this one!

By the time you sleeve a block it's usually cheaper to source a good block not to mention more reliable!

The Toyota block is a thin wall casting so the sleeve would be way thin, not good for dimensional stability in a turbo motor (staying round).

 

[cnewingham]

Sleeve's suck. I have seen some terrible sleeve jobs done before also. You can find 7m blocks pretty easy especially since everyone seems to be jumping on the 1jz wagon.

 

[bobtsgt]

I have a spare block laying around but I really didn't feel like paying $130 to have them go through it again just to tell me that the new one is screwed. Hopefully the scratches aren't too bad so I can go ahead and get some 20's. Thanks guys for the info on sleaving

 

[IJ.]

Bob: I'm using +20's in the Mule and it seems fine and a few people have posted that +40's are still safe.

If your spare block is stock bore it would be a lot better and cheaper to go that route than having the old one sleeved.

 

[Squid699]

toyota also makes 40s and 50s i think.

 

[figgie]

toyota also makes 40s and 50s i think.

actaully they make up to .06 over.. but that is REALY pushing it. After .06. The block is scrap metal as there is zero room for more Over bore after that.

 

[bobtsgt]

The only problem with the old block is I was told that it spun a bearing. But after looking at everything and the oil pan I didn't see any signs of metal shavings or nothing. I think I will just go ahead and get some 20's to help make a little extra power. Wouldn't that make it a 3.2L then?

 

[Bishop92t]

Last time I talked to Toyota they said they only made standard size and 20 over. Personally I wouldn't feel safe going over 40 over.

 

[figgie]

The only problem with the old block is I was told that it spun a bearing. But after looking at everything and the oil pan I didn't see any signs of metal shavings or nothing. I think I will just go ahead and get some 20's to help make a little extra power. Wouldn't that make it a 3.2L then?

ohh hell no. Not even close.

you MIGHt bring it up from 2995cc to 3013cc perhaps a hair more but that is it.

 

[Squid699]

Yeah, you'd have to stroke the hell out of it to get that sort of displacement

 

[bobtsgt]

Well the shop is going to machine it 20 over and see if the scratches come out. They didn't look pretty at all. Only one scratch that was the entire length of the bore. Hopefully this will take care of it. If so I'm gona get me some 20's. This thing is driving me nuts. I have everything here except the damn motor. Hopefully it will be up before July 4th

 

[Squid699]

the shop really shouldn't be boring out the block until you have the pistons you're going to use and the rings so that you can set the gap properly. Different pistons have different requirements for expansion

 

[bobtsgt]

Well I told him to go ahead and do it. Just incase it doesn't take it out I guess I can just go with 40 overs. It should work out. Plus he is calling up Toyota for all the info on the pistons.