Thread: spitfire six

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Hi, What is the displacement of the engine? I recall that the '49 Chrysler was no slouch as a flathead straight six before they went to the Firepower hemi. I recently saw a picture of Smokey Yunick on one of the threads here tuning a Hudson flathead six, so maybe with dual carbs and a split exhaust (homemade) or a custom header and a slight head-shave you would have something that can move along and maintain the nostalgia of a "time machine". Still it depends on the state of the engine at present. If it needs a full rebuild you have to decide between chasing parts or a SBC replacement where parts are far more available. I guess I am trying to say that I still like restored cars in good shape as yours seems to be and if the original performance was "adequate" it is still an interesting car (with hydraulic brakes!). On the other hand if "adequate power" is 300 H.P. then it's time for a modern V8.

I have a "Motors Manual" that goes back to 1935 and it lists the '39 Royal-6 as 241.5 cu. in. with a C.R. of 6.50:1 (low!) and 100 brake H.P. at 3600 rpm. The '50 Royal-6 was rated at 250.6 cu. in., C.R. 7.00:1 and 116 brake H.P. at 3600 rpm. That gives some idea of what to expect with boring and raising C.R. without headers or dual carbs, but it looks like 150 H.P. might not be easy to achieve with only bolt-on improvements. Still I am reminded that my Chilton's manual for Corvettes shows only 165 H.P. for the '76 350 cu. in. (a bad year, but that's my engine before rebuilding).

Don Shillady
Retired Scientist/teen rodder