'73 455 heads AIR delete

Hey all,

So I just realized that since my 455 is from a 1973 Rivera GS Stage 1, it would have came with the A.I.R. system. Sure enough I looked at the intake side and there are the A.I.R. holes. I know that TA sells a plug kit for the crossover, which I intend to get, but what about the holes on the intake side? I am going to be running an SP1 intake on this engine. Do I need to tap and plug those holes? Or can I get away with just the valley pan gasket and seal them that way? They heads have already been built and are ready to go on once the short block is together, so tapping and installing a set plug would require removal of the exhaust valves to ensure debris doesn't get in there. This route I would prefer not to go, unless I have no other choice.

Thanks for any and all help.

Scott

 

Thanks Larry,

I will have to check if the SP1 covers them. Sorry for the next question but what do you mean by plain plugs?

 

Haha, precisely. I figured a cup plug but wanted to make sure. Likely seal the plug in there with a high temp RTV to be safe.

 

I have a set of heads with AIR holes capped with the cup plugs. Never had any problems. My manifold covers them.

 

What size cup plug did you use? Also what intake are you running?

 

They were in there when I bought the heads. I never thought to check.

 

Well good news! I checked the SP1 with the '73 heads and it covers all the A.I.R. holes on the intake side. So it is going to just be some cup plugs. Do you guys think i should yous some sealent for the plugs? An high temp RTV or the like?

 

NOT RTV. Silicone in aerosol form is a lubricant. Do you want to lube those cup plugs, or seal them? RTV Silicone is the most over-used and mis-used automotive chemical.

I would use Loctite 271 or 242 or their equivalent. Any real gasket sealer would also be fine--Copper Coat, High Tack, Gasgacinch, Hylomar, etc. Another option would be Teflon (PTFE) pipe-thread sealer. Epoxy would also work.

Realistically, you should be able to put them in "dry" if the hole is clean, smooth, and round--but I like the security of threadlocker.

 

Dully noted and RTV is off the table

Since I will need Gasgacinch when installing the intake, I'll be on the look out for some of that.

I agree that they should just pop in there dry, with the intake covering them there really isn't anywhere for them to go. That being said Murphy is a real sumb***h and must have my voodoo doll. So a little extra security is welcomed

 

My 73 heads are drilled and tapped now including the heat crossover.
That put tremendous heat into intake and I had only 1 per side open before.
All aluminum heads do not provide heat cross overs so that is what I did w my cast iron 73’s.
They will still heat intake up I am sure.

 

Looks like the A.I.R. holes in the heads are 5/16ths in size. FreezePlug Factory has them in steel and brass, either material better for this application? They don't carry them in stainless unfortunately.