Mustang intake hole help

[Teal68]

Hey all,
I'm going to put a mid 80's Mustang intake on the engine in my wife's Bronco, and am curious how to deal with extra hole at the carb mount. I dealt with the same thing on a 350M many years ago, and I remember it kept burning gaskets right there. I can't remember how I fixed the problem. Got any ideas or first hand experience?
Thanks,
Tyler

Pic with arrow pointing to the hole:

 

[gick70]

Put a phenolic spacer under carb, and mill a aluminum key in the spacer where the egr slot is situated!

 

[jckkys]

Ford intentionally made a slot there to be difficult to seal. The best fix I know of is using the original EGR spacer here;https://www.ebay.com/itm/NOS-1984-1...001745?hash=item5b528d1591:g:4XsAAOSw259cUgVF. The holes in the back of the EGR spacer can be blocked with an EGR block off plate. The EGR spacer to intake gasket is a special heat resistant type here'https://www.ebay.com/itm/NOS-1984-1985-FORD-MUSTANG-5-0L-4BBL-CARBURETOR-GASKET-E4ZZ-9447-D/163905460989?epid=1227923994&hash=item262986dafd:g:K2oAAOSwAvJW~nXI. The EGR spacer is cast iron.by the mid '80s Ford knew aluminum eroded.

 

[frenchy]

There pretty proud of that plate,$149.00 seems a little high to me. I dont have a cure for your problem but would think theres a cheaper solution.

frenchy

 

[Teal68]

Thanks for the suggestions. Unless Gick's solution works it seems like just buying an aftermarket intake is much more cost effective.

 

[blubuckaroo]

Are you using factory or aftermarket heads?
Most aftermarket heads aren't delivered with the exhaust rail drilled out, and most engine builders don't drill them.
In that case, the exhaust will never make its way up there.

 

[gick70]

I had the same issue and it worked for me!

 

[Teal68]

I had the same issue and it worked for me!

Your phenolic spacer was wide enough to hold the plug in, or was the plug a tight fit?

Or.....are you saying your heads made that hole a non-issue?

 

[Teal68]

Are you using factory or aftermarket heads?
Most aftermarket heads aren't delivered with the exhaust rail drilled out, and most engine builders don't drill them.
In that case, the exhaust will never make its way up there.

I have factory GT40P heads. Do you know if they are drilled?

 

[blubuckaroo]

I have factory GT40P heads. Do you know if they are drilled?

I don't think the "P" heads needed the Thermactor rail. They're probably not drilled, but you should take an air hose and check for sure that yours aren't.

 

[SHX669]

If I remember correctly I used the EGR spacer but plugged off the outlet.

 

[ericwilkison]

I ran into the same issue, PO had just stuck the carb on top. It covered most of the hole but about 1/8" or so was still exposed. Just enough to cook the carb and boii the fuel.

I picked up an egr spacer from pick-n-pull off of a 70's F150 and grabbed the longer mounting stud also. Ordered a new set of gaskets for under the spacer plate and EGR. Then made my own egr block off plate at home. Works quite well. Although I did have to get a different air cleaner because the added height.

 

[jckkys]

I've got an EGR spacer I could give you for the shipping costs. I used the ebay auction for an easily referenced image. Kind of surprised anyone would think I'm recommending buying that one. The junk yards have a lot of them for very little cash. Anyone can do the same ebay search. Here's one for 35 bucks buy it now;https://www.ebay.com/itm/NOS-1984-1...923994&hash=item262986dafd:g:K2oAAOSwAvJW~nXI. The point is, that this is the only reliable fix for the slot in the carb mounting pad.

 

[jckkys]

There seems to be some confusion in differentiating between the exhaust cross over that heats the floor of the intake manifold, and Thermactor (air injected into the exhaust ports). All Ford heads and many after market heads are cast with exhaust cross over. Air injection ports in the heads cylinder was introduced in '75 and is in most small block heads. Surprisingly my '96 GT40 heads from an Explorer were not drilled. Thermactor has nothing to do with EGR, that takes exhaust from the crossover and introduces it into the air/fuel mixture from the carburetor.

 

[Teal68]

I've got an EGR spacer I could give you for the shipping costs. I used the ebay auction for an easily referenced image. Kind of surprised anyone would think I'm recommending buying that one. The junk yards have a lot of them for very little cash. Anyone can do the same ebay search. Here's one for 35 bucks buy it now;https://www.ebay.com/itm/NOS-1984-1...923994&hash=item262986dafd:g:K2oAAOSwAvJW~nXI. The point is, that this is the only reliable fix for the slot in the carb mounting pad.

Thank you for the kind offer sir!

And...Thanks to everyone for their suggestions. It triggered me to ask the owner of the intake if he happened to have the spacer. He does, and he is including it with the intake.

 

[blubuckaroo]

There seems to be some confusion in differentiating between the exhaust cross over that heats the floor of the intake manifold, and Thermactor (air injected into the exhaust ports). All Ford heads and many after market heads are cast with exhaust cross over. Air injection ports in the heads cylinder was introduced in '75 and is in most small block heads. Surprisingly my '96 GT40 heads from an Explorer were not drilled. Thermactor has nothing to do with EGR, that takes exhaust from the crossover and introduces it into the air/fuel mixture from the carburetor.

It all depends on the exhaust rail. That's common to both "Thermactor" and EGR. Both use the exhaust rail.

 

[jckkys]

You'll have to explain what you mean by an exhaust rail. The EGR gets exhaust gases from the intake manifold exhaust cross over that runs under the floor below the carb to heat and vaporize liquid gasoline. This exhaust comes from the #2 and #7 cylinder exhaust ports. I don't see anything that can be called a rail there. The Thermactor or air injection forces ambient air into the heads through a hole (rail ?) bored the length of the head and connected to individual holes in the exhaust ports.

 

[blubuckaroo]

You'll have to explain what you mean by an exhaust rail. The EGR gets exhaust gases from the intake manifold exhaust cross over that runs under the floor below the carb to heat and vaporize liquid gasoline. This exhaust comes from the #2 and #7 cylinder exhaust ports. I don't see anything that can be called a rail there. The Thermactor or air injection forces ambient air into the heads through a hole (rail ?) bored the length of the head and connected to individual holes in the exhaust ports.

Thanks for correcting me. I had both of the systems connected in my mind. %)

So #2 & #7 have two holes bored in their exhaust ports? One for the Thermactor system, and one for the exhaust heat riser/EGR?

 

[Broncobowsher]

Thanks for correcting me. I had both of the systems connected in my mind. %)

So #2 & #7 have two holes bored in their exhaust ports? One for the Thermactor system, and one for the exhaust heat riser/EGR?

The exhaust port to intake is just heat riser/EGR supply.

The Thermactor is air injection into all the exhaust ports. This is done either through a passage on the ends of the heads that has a port that drops into every exhaust port, or done externally on the exhaust manifold. These are independent, even isolated systems.

 

[jckkys]

The #2 and #7 exhaust ports have a smaller port cast into them that goes to the intake manifold gasket surface while the larger portion of the exhaust port goes to the exhaust manifold. The intake side port can be seen as an oval shaped hole dead center of the intake gasket surface of the head.