View Full Version : 351 Indmar Exhaust Manifold

05-11-2010, 02:37 PM

I know there are plenty that have cleaned up their Exhaust Manifold Plug threads using a tap. I need to do this and was curious if anyone knows the size of the Tap that needs to be used.


05-11-2010, 02:57 PM
I believe it is 3/4" NPT (pipe thread)

05-11-2010, 03:04 PM
Depending on the level of corrosion, a small stiff metal brush works well and is likly less expensive, particularly if already have one in your toolbox. A round brush such as the type used to prep copper pipes before sweat fitting seams like it would be perfect.

05-11-2010, 03:21 PM
yeah used a wire brush but didnt work completely on all, so just going to use a tap for a clean cut. Thanks all!

05-11-2010, 03:54 PM
I believe it is 3/4" NPT (pipe thread)

This is the right size. I know for sure because I did mine this year.