Car of the Week: 1956 Chevrolet Bel Air

By Raymond E. Moss

I purchased this 1956 Chevrolet Bel Air two-door hardtop new at Gene Jantzen Chevrolet in St. Louis, Mo., and it’s one of few — perhaps 12 — built specifically in the General Motors St. Louis plant for demonstration at dealers in the St. Louis area. I have seen three of the others. What makes this 1956 Bel Air special is its dual-quad “Corvette engine,” which was rarely installed in full-size Chevrolets that model year.

In addition to the dual carburetors, my car is equipped with a 3/4 camshaft. The carburetors are presently fitted with the small Corvette-type individual air cleaners, but I do have the original “batwing” air cleaner for it. It also has the same heads as the next year’s 1957 Chevrolet fuel injection engine with larger ports, hardened valves and dual ram’s head exhaust manifolds. My 1956 Chevrolet also has the dual-point lock spark distributor with centrifugal advance; there is no vacuum outlet plug on the intake manifold. It also has the standard three-speed manual transmission with close-ratio first and second gears and a 11-inch clutch with 3.70 gears in the rear end. The 265-cid V-8 has solid valve lifters, which appears especially uncommon. My car is further fitted with the standard radio, a heater and a padded safety dashboard. The cost of the car with the $242.25 “Corvette engine” was $3,178.92; with the added cost of financing ($375.54), I paid $3,554.54.
It has never been determined if this dual-quad “Corvette engine” was installed at the factory or by the dealer. However, I do not think it makes sense that a dealer would change an engine for just $242.25.

Trouble with my car started early. Less than 1,000 miles into driving it, the engine caught fire and the hood had to be repainted. The rear carburetor and electric windshield wiper motor had to be replaced. It caught fire a couple more times, but it wasn’t as big of a deal. After that, the car began consuming spark plugs. At 13,000 miles, I was on my 12th set of spark plugs. During that time, it also started overheating and the dealer flushed the system. This didn’t help, so I got out my $2 timing light. The pointer is supposed to hit on 9 degrees advance, but it was retarded 4 degrees. That means it was 13 degrees too slow. After putting it to the right setting, it never overheated again.
Back to the spark plug problem. The service department mechanics were also perplexed about this issue. I then approached the service manager, Bill Smith, with a proposition. If I could find the problem, would the dealer stand behind the good reputation of GM and pay for what it may cost? He said they would.

The first thing on my agenda was the forward carburetor. I removed it and that turned out to be the right move as three of the four holes in the intake manifold were pink from the ethyl gasoline of those days, and the fourth hole was loaded with “black velvet” (burnt carbon). Then I removed the whole manifold and the right head and quickly discovered the cause of the fire. The number two intake was seated on one side, but the other side was standing open about 1/8 inch and was pumping raw gas in and out of the chamber at the right and wrong times, creating constant fire hazards. The dealers stood behind their word and supplied all the gaskets and the new valve. That’s when the service manager told me those valves were not standard. They were specially hardened, but were also bigger and were the same heads that were on fuel-injected 283 engines.

By 1963, I decided the Bel Air was a keeper, despite its early problems. That year, I built a two-car garage so it didn’t have to sit outside any longer.

In 1971, the engine developed a rattle that I couldn’t find, and with 114,00 miles I pulled it out to rebuild it. The number eight piston was the culprit. I bored it .30 over, installed new Thompson drop-forged pistons and took .30 off the crankshaft. I installed a new 098 cam because I couldn’t find a new 3/4 bump stick. I also installed all new bearings and rebuilt the heads. I put it all back together myself, including the original solid lifters.

Since the engine rebuild in 1971, I have put about 15,000 more miles on the car and it’s only had three light spells in the rain.

It would be interesting to know how many of these dual-carbureted full-size 1956 Chevrolets are still in loving hands, because most were certainly lost to stock car racing and drag racing.

Tri-Five expert Bob Wingate believes there were less than 500 full-size dual-quad Chevys of all horsepower ratings built by all GM factories in 1956. He had one for sale years ago that was the same as mine. Interestingly, his car was also built in St. Louis.