Okay guys I had a very scarry experience today. I bought the reducer bushing that WP told me to do and When I screwed it in to the sensor slot, it cracked of flush with the heads. Thankfully (thank god) that I was able to get it out with an extractor. I don't think im going to go that way again.

My question is, does GM make a senser that has 1/2" threads rather than the 3/8" threads I got right now??

 

2 things.

Bushing was brass, right? Sounds like you overtightened it. Use teflon tape/paste, and install it snug not tight. If you really want a sensor with 1/2 thread, you can probably find one for a different application but you will need to look yourself for sure. Standard Ignition has a great parts listing book that lists the important information you need to know in most cases. Best I have seen as far as a relatively easy to access source.

 

Which sensor?

If you need a temp gauge sensor, get one for an older vehicle, like a 79 Z28 350 or something. The holes in all heads were ½" pipe until the 305 "light" heads IIRC. If you need a fan switch you may be out of luck, unless Hypertech or some other aftermarket source like that offers one.

I am using the brass bushing in the 186 heads for the fan switch in my 83, no problems.

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"So many Mustangs, so little time..."

 

Actually, places make ADAPTERS so you can still use the stock temp switch. email or contact johhny hunkins (editor of GMHTP) and he had to do this for his trick flow heads. he could let you know. they might even have them at a parts store. just find a brass fitting that is 1/2 and had a thread in of 3/8, that should work.

 

I had to Shave the brass fitting down for the fan switch to get it to go in flush with the block.


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Black 90 IROC, L98, A4, 323 gear. SuperRamed 406 in the works!

 

Auto parts stores dont't have 'em but I picked one up from home depot in the plumbing section.