(ENGINE) identifying what these holes are for
 

https://cimg1.ibsrv.net/gimg/www.rx7...39b1a4bfda.jpg
https://cimg2.ibsrv.net/gimg/www.rx7...d81a235f3b.jpg
Its a 12a from 1978 that i just rebuilt, i have no clue what these 4 holes are for the first picture is the exhaust side. The second picture is the sparkplug side.

also I did not get the chance to disassemble this 12a my grandpa did :/ but anyways, ive also read through the haynes manual thoroughly and can't seem to find a section on these bolts or what goes there

It's a throwback to the early 70s. Probably to be backwards compatible for motormounts in a chassis we didn't get in this country. They lasted up to the nitrided R5 irons like what you have there. Later irons didn't have them.

so should i pluge these or should i leave em, more geared towards plugging them but not too sure
​​sure

Plug them? Why? They don't lead to anywhere.

plug them as in thread a bolt in, and on the exhaust side one of the holes leads to the flywheel id prefer dust and dirt not get it yanno. The other 3 are dead ends

ok