Should I pull the emissions system from this car?

Question:

I need some advice on whether or not to remove the factory installed Thermactor Emission System from my 1966 Mustang with a 289 cid, two-barrel carb engine. This car was built in San Jose, California, in March 1966 but it now resides in Michigan, where no emissions controls are needed for that model.

My main concern is that the air pump puts air into each head to each exhaust port. Will I harm the valves if I plug off these ports? The distributor vacuum is not used and according to a label the timing is set at 1-degree BTDC.

The car is in excellent condition with only 37,000 miles. I would like to put the engine back to stock without the emissions controls. I would appreciate your input as nobody around here has had any experience removing these emissions controls.

Answer:

I’m somewhat surprised that nobody you’ve spoken with has experience removing the emissions components from a vintage Mustang. As you probably know, in the good old days this was quite commonly done. Maybe you’re hanging around youngsters who weren’t there in the good old days!

The answer to your question is no, removing the air pump and plugging the holes with normal pipe plugs will not damage the valves.

The function of the air pump was simply to inject “fresh” air into the exhaust gas to cause a chemical reaction that reduced the amount of harmful emissions. Removing the system will not impact engine function, longevity or performance in any noticeable way.

I believe that the emissions system on your car was installed only on cars destined for initial delivery in California. That, combined with the fact that so many of these systems were removed over the years, makes them rather rare today. If I had your car, that you say is in excellent condition with only 37,000 miles, I would not remove the system.

At the most, I’d remove the belt that drives the air pump and leave everything else in place. If you do choose to remove the system I highly recommend saving it because someone will probably want to reinstall it in the future.