Temperature sensor location
 

I have an offenhauser dual quad intake on my motor. Passenger side front has temperature sensor. Drivers side has just threaded hole. I’m assuming it’s the same size. I guess I need a plug there. What is best to use and what size? Yes I completely forgot and filled with antifreeze. Reminded myself for days and remembered when it stammered time flow out,ugh!!!
Thank you!

I want to say it's 7/8" Or possibly 15/16" It's a fairly large hole.

The tape-measure measurement of the hole is helpful, but not useful as-is. The hole will be pipe-thread. Pipe thread is measured based on the ID of the pipe, so the size of the hole has no relation to the markings on a tape measure. the nominal size of the hole will be much smaller than the tape measure indicates.

It's probably 1/2" pipe thread. Pipe-thread plugs are available at every parts house or home-improvement center in America. Given a choice, I prefer brass to steel; steel plugs tend to seize in aluminum manifolds. I've seen, but never used aluminum or stainless steel plugs. The last ones I bought were brass, and came from Amazon.

Allen- or "Hex" recess plugs tend to look nicer than the style that have a big hex "bolt head" sticking up out of them. They're harder to remove if they seize, though.

https://static.summitracing.com/glob...dl-8052_ml.jpg
https://www.summitracing.com/parts/edl-8052

https://static.summitracing.com/glob...21006-2_ml.jpg
https://www.summitracing.com/parts/sum-921006-2

Whatever plug you select, use some anti-gall thread paste as a sealer. My preference is Loctite/Permatex 592 "PST" (Pipe Sealer with Teflon) This stuff has a hardening chemical in it, somewhat like Loctite thread lockers. Wonderful sealer. Prevents thread seizure. Makes disassembly a breeze. Available in most any automotive parts store, but not likely to be found at Lowe's, Home Despot, etc.
https://www.amazon.com/dp/B0002KKTH2...v_ov_lig_dp_it

Thank you for the info guys!!!

X2, 1/2" pipe it is.