Hey guys i have a spare 16v and 20v motor lying around minus 20v head,and plan on doing a twin carbed conversion with the 16v,however because i have looked at the 16v motor warrant sheet it failed on a few of things for the motor (excessive smoke and whatnot) and my mate being an engine rebuilder would the the 16v head bolt straight up to the 20v block or is there little variations.my mate says if the 16v block has to be used it will cost a lot more as the 20v motor was my sisters and it was the oil rings that let go only.any help with this would be much appreciated thanks.

I did not do the work myself, but my AE82 had a 20v silvertop block with a 16v bigport head. The engine ran fine & only died when an oil cooler line blew off, it lost pressure & a crank bearing died. Get your engine builder to double check oil/coolant passages & it *should* work okay.

I assume you would be urnning 16v pistons as well?

I found 20v pistons inside when I stripped the motor down, did make me wonder what the compression ratio might have been like.

Flycuts wouldn't have been ideal either...

There were no marks or damage on either the pistons or the valves that I could see. Cylinder head is fine, aside from needing the usual needing new valve stem seals. I haven't done any measuring, but I'd dare say if the block/head were skimmed/shaved at all things would've gotten messy very quickly.

 

If you go quoting valve sizes off the top of your head, I will freak out just a little. :P

Done many times, I think the only trick is to use a head gasket that matches the head. Hit up SamQ.