Im in the process of tapping the intake and plenum
threads .. they were alil beat up by the previous owner
and I want to ensure that the runners seal nicely.

I wanted to confirm the thread size of the aluminum
intake and plenum ..

my best guess is a 5/16th or 3/8ths fine thread
or is it metric ??

am I hot, warm or cold??

 

8mm by 1.25. When I modified my plenum and runners for increased air flow I rechased all the threads with a bottoming tap. On some of them I was able to deepen more and use a longer bolt. Hope this helps you out. Allen

 

It sure does !!

thanks alot, the aluminum threads on my intake are
pretty beat up .. and dont wanna risk chewing it up
even more than it already is

the plenum I could probally leave alone, but Im a fan of
thoroughness, and will be rechased

why is metric on top of an american motor anyway??

thanks alot allen,
youve helped me out more than once!!