[nikellty]

Here are some pics any one else have those holes in their intake manifold as shown in the last picture?

[BBFcapri]

Everyone with factory heads built after the A.I.R. pump was invented has them. if you want to plug them go to the parts store and ask for thermactor plugs. they are trheaded on the inside for accessory mounting if you put them on the front.

hope this helps!

[Ivy66GT]

Those holes should not be in an intake manifold but in the head near the exhaust ports; isn't that an exhaust pipe I see in the last picture?

All air pump cars with heads cast in Cleveland (CF on intake manifold in picture #2) starting in '66 had such holes for an external air line from the air pump. If you can find anyone selling those plugs new I would be amazed. Most just buy an appropriate bolt at the hardware store to plug the holes.

[Dave]

Yep, for the rear ones, just use a 5/8"-11 bolt/setscrew. If you need the ones in the front with the internal threads, they can be had at a Fastenall store for about 30% of other places. I just got package of five for $15.
Dave

[nikellty]

picture #7 is NOT my engine...sorry!

[BBFcapri]

Originally Posted by Ivy66GT

Those holes should not be in an intake manifold but in the head near the exhaust ports; isn't that an exhaust pipe I see in the last picture?

All air pump cars with heads cast in Cleveland (CF on intake manifold in picture #2) starting in '66 had such holes for an external air line from the air pump. If you can find anyone selling those plugs new I would be amazed. Most just buy an appropriate bolt at the hardware store to plug the holes.

Trick Flow® Small Block Ford Thermactor Plugs - SummitRacing.com

they are actually pretty easy to find, the problem most people have is not knowing what they are called...

[66Sprint200]

Ivy66GT, my 66 200CI has the holes and they are technically in the intake manifold. They are in each of the little indents and they go right into the combustion chamber on mine. They were already plugged when I got the car.

[Ivy66GT]

Originally Posted by BBFcapri

Trick Flow® Small Block Ford Thermactor Plugs - SummitRacing.com

they are actually pretty easy to find, the problem most people have is not knowing what they are called...

As I said above - I am amazed they are for sale. Those don't really look much like an original, at least not the early ones, since the Ford part had a hex bolt head on them and a tapered lower end which I think mates to a tapered seat inside the head. I am doubly amazed since a 50 cent bolt looks more original than their $8.50 part.

[Ivy66GT]

I can't say much of anything about the 6 cylinder since its been decades since I have touched one. But they had the exhaust and intake manifolds on the same side of the head. The V8s are a cross flow head and the T/E holes are on the exhaust manifold side of the head which is about 5" away from the intake manifold. Since its a 70s engine its not exactly like any that I have even owned. Some of the heads used an external air pipe and some had a internal air passage cast into the head. #10 picture may be an end view of one of the internal plumbed systems. The more I look it the more I think that is an end shot of the head, the blue edge of the valve cover is above and there is a set of tube headers on the right side. The heads have a freeze plug on that front corner.

[BBFcapri]

Originally Posted by Ivy66GT

As I said above - I am amazed they are for sale. Those don't really look much like an original, at least not the early ones, since they had a hex bolt head on them. I am doubly amazed since a 50 cent bolt looks more original than their $8.50 part.

funny thing about thermactor plugs, they are not the same thread as a $.50 bolt. they are pipe thread. if you are going to do a job, you may as well do it right the first time.

[Ivy66GT]

Re-reading that ad, those Summit parts aren't even plugs although they somewhat claim to be. They are to reduce a 5/8-11 threaded hole to a 7/16-14 hole. Either of those are NOT pipe (tapered) threads but standard UNC bolt threads.

Since I think the picture above is of an end hole in a head, not a hole above an exhaust port, the required plugs may well be different.

[Ivy66GT]

Here is another source for the plug and it does seem to be a true plug although odd with internal and external threads. They also have a link to compare them to the ones from Summit. A disclaimer is given that not all heads may have the same thread.

http://www.store.partsdinosaur.com/product1521.html

An original Ford plug like I am talking about looks like this:

DSC Motorsports - Part Details

These are for a 390 which might, or might not be a different thread. The shape is the same as that used on the small block Ford.

[nikellty]

installed 2 plugs.
now just waiting to turn it over....

[BBFcapri]

Originally Posted by Ivy66GT

Here is another source for the plug and it does seem to be a true plug although odd with internal and external threads. They also have a link to compare them to the ones from Summit. A disclaimer is given that not all heads may have the same thread.

SBF FORD Cyl. Head Smog Port Plugs (Thermactor)

An original Ford plug like I am talking about looks like this:

DSC Motorsports - Part Details

These are for a 390 which might, or might not be a different thread. The shape is the same as that used on the small block Ford.

i have never seen the ones for the 390 before in the bottom link, that is good to know.

they thread the inside so you can use them when you mount accessories on the front of the engine. you are right, they are not pipe thread, but if you ever get a chance, look at one side by side with a bolt. the threads are cut deeper. they are a weird thing, but i will always spend the money since the most you could possible ever need is 4.

one time i bought a pair of heads for a 5.0 i was building in the 80's (my first or second) and the heads the machine shop swapped out with my old ones had the plugs in the same end. i put them on and one bank was plugged in front (like they should be) ad the other head was plugged in back. took me a while to figure out my exhaust leak on the passenger side front corner!!

i had not istalled any accessories yet, and the bolt for the alternator threaded into it.

anyway-

good luck with your car!