Topic: Engine heads

[Mudder]

I'm not sure if I'm missing something here, but why won't a 22r head work on a laser block 22re? I know why it doesn't work the other way around because of the domed pistons which would contact the valves. Now I'm specifically talking about the 81-84 22r which have the same piston diameter and same overbore. I also know there is a difference of .190" between the two blocks, but the 22re pistons sit flush. I also know the 22r cylinder head is 3.290" tall while the 22re head is only 3.130", but even with that in mind all you'd need is a long timing chain.

Is there something I'm missing as to why everyone says you can't put a 22r head on a 22re?

[H8PVMNT]

I think the timing chain is the real issue.  Cam timing would probably be all whacky, which could be fixed with an adjustable gear.  The early head could be machined I suppose.  Not sure if the timing cover is different depth or not.

Other than maybe putting a 20r head on a laser block what would be the point?

[jimbo74]

there are 2 different styles of 22r...... their is the early version and the 22r laser block version

[Mudder [OP]]

And that change was 10/84. I only ask because I'm looking to drop the compression ratio in my 22re for a turbo and doing a head is a lot easier then doing pistons. I believe I have the early 22r but I'll have to double check the door plate on my truck. I can tell you all my EFI stuff bolts to the 22r head.

[H8PVMNT]

Those flatter pistons should drop compression for sure.

[Mudder [OP]]

The truck was produced 12/83. So if we assumed that the old 22r I pulled was the OEM engine it'd have the non laser block for sure. The engine in there is a laser block engine. I also know the exhaust ports are different but I doubt that'd have an effect on a turbo. I'm just not sure what I'm missing since everything I've read says the 22r head won't work with a 22re block. All the holes on the bottom of a 22r head are the same as a 22re head it seems.

[:)bestgen4runner]

The early engine has a different deck height. They are not interchangeable.

http://www.lcengineering.com/LCTechPages/techpages/TechNote48.htm

[arlindsay1992]

If you put an early head on a late block the cam chain will not fit, it's not long enough. In my younger years before knowing the difference I bought a used engine to fix up my late model 22RE. I cleaned and redid the head all up, bolted and torqued it down before finding out about the differences.

[arlindsay1992]

Also, don't confuse 22R vs 22RE with early vs late engine. R/RE just determines if it's carbed or EFI the heads are the same for each. The heads are not the same for early vs late engines.

[Mudder [OP]]

Also, don't confuse 22R vs 22RE with early vs late engine. R/RE just determines if it's carbed or EFI the heads are the same for each. The heads are not the same for early vs late engines.

Actually mid '83 you can bolt an EFI manifold to it. The earlier 22r's 80-83 you can't unless  you tap for holes. And 20R heads you can't either unless you get a custom head. As for my question the reason why you can't is because there will be a different centre for the cam to crankshaft. We already had discussed about the different heads and I mentioned them in my initial post. And H8PVMT did answer the question I just didn't read his post correctly.