SBC question ..what size bolt? (1 Viewer)

[Bennett]

dumb question...
Anyone have a small block Chevy on hadnd that can confirm the size of these spark plug heat shield cover bolts..? see yellow circle.

I tried 1/4 " and they would not fit.. first couple threads took but got tight fast.

I am wondering if there is a different thread pitch needed?



thanks

 

[llih]

I am going to guess 1/4 or 5/16.

 

[Plowboy]

The bolts are 1/4x20, 3/8 long