All Small Six Thermactor missing, any issues?

[gserafini]

So my mustang is a '66 200 that I found out has the code for originally having a thermactor system built in San Jose. I am remembering now when I got the car when I was 15, my dad and I removed the thermactor because it was missing some pieces and not working. Totally forgot about this. Never even thought about it again and I don't believe we did anything else to the car except pull that unit. Are there any issues this could cause? I read somewhere about plugging holes for it but definitely didn't do that 15 years ago. What improvment would this do? And is the PCV system affected by this?
I had an exhaust shop install headers for me when I was like 17, so I don't even know if they plugged those holes or did anything while they had the manifold off.
They also made a dent in the wheel well in order for the headers to fit....instead of just bending one of the header pipes....didn't care at the time but now i'm bummed they did that. I digress ha

 

[TrickSix]

I don't know much about the Thermactor system. But as it injected air into the exhaust ports, there must be openings into them. Those holes have to be plugged or else you'd have six big exhaust leaks. Are there any funny looking plugs in your head's exhaust runners next to the intake log? What's the head casting number? Post a pic. If you do have a thermactor head you might want to get a different one, the Schjeldahl brothers don't like them!

 

[Frank]

Yeah, ditto to TrickSix above: if the system you're describing is an air injection system into the exhaust, then where ever it entered the system, it's plugged or you'd have an intolerable exhaust leak. There's no downside to it's being removed. It is not associated with the PCV system.

 

[gserafini]

Got it that’s what I’m worried about but having a hard time telling if I have an exhaust leak, should be pretty noticeable. I’ll add some photos here

 

[gserafini]

Sorry having a hard time getting good engine code photo I can try again later

 

[DON]

Looks like you have headers. The ports would have been on the original exhaust manifold. You should be fine

 

[DON]

Got it that’s what I’m worried about but having a hard time telling if I have an exhaust leak, should be pretty noticeable. I’ll add some photos here

It would be noticeable, sounds like a whezzen tic tic tic. Although if it was on all cylinders, it would be pretty noisy. I have never heard one from all cylinders

 

[gserafini]

Looks like you have headers. The ports would have been on the original exhaust manifold. You should be fine

Oh that makes sense, sweet! Thanks!

 

[gserafini]

It would be noticeable, sounds like a whezzen tic tic tic. Although if it was on all cylinders, it would be pretty noisy. I have never heard one from all cylinders

Hmm I hope I’m not the first on all cylinders haha

 

[TrickSix]

Got it that’s what I’m worried about but having a hard time telling if I have an exhaust leak, should be pretty noticeable. I’ll add some photos here

In your fourth picture here, just above the C6DE-6090 on the intake log, I see two hex heads. The dark one above the 6090 looks like a head bolt. What's the shiny one above the C6DE? A plug for a Thermactor port maybe? Are there five more of them along that area? The pics don't show that part of the head clearly. The handbook seems to state that the part numbers are the same for Thermactor and non-Thermactor heads. But they say to avoid them, so they must be different. I wonder if the air injection ports are machined in later and aren't actually in the exhaust manifold.

 

[TrickSix]

Okay, I spent a couple minutes on google while eating breakfast. Saw mostly 289 pics but I didn't look long. Ford actually made a hex-head plug for the ports when a Thermactor system was removed. The "injectors", not sure what they're called, were pressed into the head, and protrude into the port. That's why they are frowned upon for performance applications. Pull your headers off and you could probably see them way up in your exhaust ports. Maybe they could be machined out with the head removed, and a nice flush ended non-protruding plug made up so as to not disturb the exhaust gas flow.

 

[sixtseventwo4d]

Most likely you have a header gasket that has split; they simply don't hold up to time. With the engine running and the air cleaner off, squirt or dribble a minimal amount of trans fluid into the carb; not too much (about a teaspoon), you don't want to stall it or foul the plugs. Watch around the header flange for smoke and poof- there's your leak. Having someone with a work glove hold a rag against the end of the tailpipe will help show all the leaks when smoke-checking. Do this outside so you don't smoke up the garage.

 

[78_200_C4]

So my mustang is a '66 200 that I found out has the code for originally having a thermactor system built in San Jose. I am remembering now when I got the car when I was 15, my dad and I removed the thermactor because it was missing some pieces and not working. Totally forgot about this. Never even thought about it again and I don't believe we did anything else to the car except pull that unit. Are there any issues this could cause? I read somewhere about plugging holes for it but definitely didn't do that 15 years ago. What improvment would this do? And is the PCV system affected by this?
I had an exhaust shop install headers for me when I was like 17, so I don't even know if they plugged those holes or did anything while they had the manifold off.
They also made a dent in the wheel well in order for the headers to fit....instead of just bending one of the header pipes....didn't care at the time but now i'm bummed they did that. I digress ha

It sounds like your 66 Mustang is a California Emission model 200 with a centrifugal-vacuum advance distributor.
My wife drove a 1966 San Jose Sprint six 200 Mustang coupe that I maintained for 14 years.
Removing the thermactor + air pump in the old days could make the 66 CA emission Mustang fail a valid Smog inspection if the licensed inspector did his or her job properly. Before we sold our modified CA emission 66 Mustang I installed an earlier 170 head. I knew that the local smog inspectors either didn't care or didn't know the difference between a 66 Federal emission 200 and a 66 California emission 200. Back then (1980's) the California BAR didn't care about smog inspections. It took the feds to make the BAR into what it is today.

 

[78_200_C4]

Here is a thermactor head showing that the air is injected into the head not the exhaust manifold.