Hello all, long time lurker, first time posting.

I have a L20A engine that I am currently rebuilding and I have some questions I am hoping someone can help me with since there’s not a lot of information on the earlier engines in the US.

First, my problem is the original E30 cylinder head was missing and all I was able to obtain was the E31.  It’s my understanding that the E30 had smaller valve(s) and a smaller combustion chamber.  I think the E30 was 36-38cc and the E31 is 42.5?

My second issue is, the original pistons were garbage, and I can’t seem to find factory replacements. I have been looking at the KAMEARI light weight street pistons (SP-L20401-79) that are 79mm. I understand that I would need to go to a full floating rod to utilize these. I was looking at the CXracing L24 rods which are 133mm long like the L20a rods.

My questions are, possible valve interference with the engine block due to the small boar and the oversized E31 cylinder head valves.  Next, low compression ratio due to the higher cc head and the new pistons.

Any advice on this situation would be much appreciated.

Links for the rods and pistons below:

Pistons

https://www.kameariengineworks.co.jp/4-catalogue/2024.8.7-English-cataloge-v4/E0011.pdf

Connecting Rods

https://www.cxracing.com/ROD-L6-1330x6?srsltid=AfmBOoq1seHAZKHRIzfi8Ty5q1oPRFdG1V-m7n75OsCHTH5WlRE-H_q4i8Y

I happen to have a complete E30 head that I have never been able to sell, quite a niche market for sure. I’m in Western Canada, send me a PM if you want to discuss getting it to you.