05/09/2025
What a beautiful piece this 1957 Chevrolet Bel Air is - numbers matched 283 CID with a 4 speed Muncie. The car had been sitting for around a decade, if not a little bit longer. One of the major concerns the customer had noted was a terrible rear main seal leak. Upon further evaluation, we confirmed that it was a rear main seal and we proceeded with removal of the rear main bearing cap for access. Upon removal of the rear main bearing cap we discovered that the rear main bearings had worn down to the intermediate bearing layer. Further evaluation had found that this was originally an automatic car; the crankshaft from the factory is different between an automatic and a manual. Doing the conversion required some Machining of the crank and a special pilot bushing. The Machining was done, but the pilot bushing that was utilized was the incorrect size, shaved down by hand, mushroomed into the crank and drilled open to accommodate the input shaft. Fortunately, the input shaft did not break and the engine's rear main bearing had taken the brunt of the force. Upon consultation with the customer, we landed on doing a full rebuild on the 283 and a tear down of the Muncie for evaluation (input shaft bearing was in quality condition and no damages to the gears) and reseal. The crank did suffer some damages and did require that the main journals be ground down .010. Assembly went very well. Initial ignition timing set at 10° BTDC and she fired right up in about one half rotation. After the break in procedure, she was taken out cruising and we slammed some gears for tuning. We also installed lowering springs on the front and rear, including tubular control arms and the stance is phenomenal now - see prior posts for some detailed work.
It was an opportunity of a lifetime to work on this beauty and we are grateful for that opportunity. Thank you!
For any and all Automotive needs, foreign or domestic, classic or modern, 4 Speed Automotive & Diesel is here to help.
-Brian
