If you're installing any cam, do yourself a favor and buy a degree wheel and check the cam against specs. I have degreed several stovebolt cams over the years from factory to Crower to Howard's and the only ones close to its spec are the original factory cams, not the stock repops. Back in the day McGurk ran dyno tests on a 261 with various mods and determined that more exhaust duration improved things with no other changes. Of course his McGurk 3/4 race cam was the best all-around compromise but the factory 261 cam, which he said in the same Hot Rod Magazine article, was the same part number as the Corvette cam came in a close second to his cam.
What I ended up with in my 235 is a Crower with more lift and duration than is probably optimum at 0.450 lift and 215 deg @0.050 lift. Same profile intake and exhaust. None of these is what the spec sheet showed. I advanced it 4 deg with a key which was as much as I dared due to intake valve/piston interference. I checked it with modeling clay then double-checked with a dial indicator after final assembly. I got the recommended 0.050 minimum.
My starting point for TDC was to use a strap and a bolt across #1 cyl to stop the piston, go back the other way to stop and divide the degree wheel readings by two. TDC found this way was not what the UC mark on the flywheel indicated. The flywheel was not original to the engine. UC mark is off by about 4 degrees IIRC.
Cutting to the chase the engine pulls hard at 2800-3000RPM but you better think about shifting down if it drags below about 2500. The fire sort of goes out. That said it will pull down to about 1400 and recover smoothly. FWIW this is a hotter cam than I would want if running a straight 4-speed SM420. I can run the engine between 2500 and 2900 right up through the gears. It works well with a 3-speed brownie or perhaps with a 2-speed axle. I never pull it over about 3300 and only then to make the next gear on a pull, so all that capacity above there is for naught. Not enough carburettor anyway.
1951 3800 1-ton "Earning its keep from the get-go" In the DITY Gallery 1962 261 (w/cam, Fenton headers, 2 carbs, MSD ign.), SM420 & Brown-Lipe 6231A 3spd aux. trans, stock axles & brakes. Owned since 1971.
