Like a dummy, I tapped out the threads for the heater hose fitting in my small block aluminum intake with the wrong tap. What would be the best way to fix? The fitting now screws all the way down with no interference fit and I`m afraid it will leak even with pipe tape.

Is it flat enough that you could consider thread sealant and a copper washer?

Not sure I will have to take another look at it.

You can partially weld it up then drill and re-tap with an NPT tap. Or just try and use the next largest NPT thread tap and do something unique with the hose fitting.

Buy a brass reducer bushing at the hardware store with the correct inner & outer pipe threads.

Sounds like he might have used a regular thread tap instead of NPT.
If there is enough meat on the intake you could take it to the next size NPT and install a brass reducer bushing to get back to the right size.

Almost sounds to me like he used an NPT tap but went too far on the taper and the fitting might not start to bite until it's bottomed out.

some years ago i used a epoxy type repair where you put it on the threads screwed it in then unscrewed the fitting and waited for it to setup,i used it on a stripped ford brake caliper,i cant remember the exact name ,but it was something like thread renew,etc,etc
it worked great seems like you had to put something on the good threads first so they would release after it was screwed it before it cured,its been a few yrs back ,my memory is pretty spotty in my old age

what about JB welding it in there permanently? I've JB welded fittings into the cooling system for cooling routing mods & No issues.

Yes, I used a regular tap. The epoxy will probably work and I will look into it. I will look into the brass bushing idea too. I have to dig the intake back out. After I messed it up I put it away and now I think I`m going to try and use it. Thanks for the helps guys.

They sell NPT thread repair kit's,

https://www.mscdirect.com/browse/tnpla/94204013?cid=ppc-google-New+-+Threading+-+PLA_seJ7a6JRI___164110843911_c_S&mkwid=seJ7a6JRI|dc&pcrid=164110843911&rd=k&product_id=94204013&gclid=EAIaIQobChMI_M2v04P63QIVEdbACh3AJAK6EAQYAiABEgLNY_D_BwE

I'd just try to in weld the fitting in place

Welding a steel fitting into an aluminum intake would not work very well.....

True, but they make aluminum ones too

JB weld. NPT common plumbing iron fittings into alum tcover. solid as a rock.

Please don't use black iron fittings on your mopar small block. You make us all look like hillbillys. IMO

Nothing wrong with mopar cooling systems, so you don't have to "make it better"

This will be out on the dirt track so it'll all be good. The hood will not be popped unless I win & get teched.

Aren't worried about weight? Even worse if your going to use it racing IMO. Sorry.

Actually that is a VERY valid point.

RR, why not a short chunk of heater hose, rather than all those fittings ?