Thread: Greetings from the UK

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Tech1, probably so since usually the cams of those days really emphasized low rpm performance. I too have a "Motor's AUTO REPAIR Manual", copyright 1951, which covers most American cars from 1935-1951. Our new friend has not told us yet how many spark plugs are in the head of his Pontiac. There were two engines in 1948, a 239.2 cu. in. six cyl and a 248.9 cu. in. eight cyl. No torque values are given but the six was rated at 93 H.P. @ 3400 rpm and the eight was rated at 107 H.P. at 3700 rpm. Probably the H.P. peak was past the torque peak but we can use the formula:

H.P. = Torque x (rpm/5252)

to calculate the torque. For the six that would be about 144 ft. lb. at 3400 rpm and for the eight it would be about 152 ft. lb. at 3700. Since it is relatively easy to get 300 ft. lb. of torque from a SBC 350 that is a good reason to consider that option. By contrast the stock '48 Ford flathead put out about 175 ft. lb. of torque around 1900 rpm from a 239 cu. in. engine, although that fell off to about 140 ft. lb. around 3500 rpm. I don't see any mention of the rear end ratio in the Motor's Manual. I can only recall two Pontiacs from back at that time. One was the "sedan on a Woody frame" my buddy built and another was a '48 convertible. As I recall the convertible could hold up to six cheerleaders with the top down and the owner really flogged the engine, but I doubt if it could keep up with the many '41 Ford 59A flatheads of that era because the luxurious body was on the heavy side! Well, again If I had that car I would just wash and wax it and add dual pipes with chrome tips and a CD player and just enjoy cruising.

Don Shillady
RetiredScientist/teen rodder