What size bolt is this?
 

Hey guys, got a quick question. I got my head ready to go and just need to plug this hole. Anyone know what size the bolt is and what thread pitch? I don't have anything to plug it.

https://www.miataturbo.net/attachmen...ine=1375575315

Also, should something be plugging this hole on the oil pump?

https://www.miataturbo.net/attachmen...ine=1375575315

No, i believe that lower one is for your crank angle sensor, which you don't have installed, but nothing needs to plug it if you truly don't need the sensor itself.

No idea what the rear head thread size is, sorry.

IIRC the rear is M14x1.50. The front hole is threaded for the timing belt covers, which you need to run if you expect to actually set the timing on the engine.

oops, wrong side for the crank sensor, so sav is right, that's a cover bolt.

I figured it was something like that (I had to strong-arm my cover back on since I spaced and put the balancer on first..). I just noticed the thing at the bottom of there that looks like it's plugging something.

The bolt for the back of the head is only half an inch long too, wtf. I cut a bolt to put in there but the threads were the wrong pitch and messed up a bit of thread, but I found a proper bolt for the hole and it's plugged now.

Same thread as the ECU coolant sensor?