Just picked this up this morning, it's a bespoke item for my 1928 Chevrolet tourer. I've got some builders in at home doing some alterations, although they aren't technical car people, they were all over this billet crank when I unwrapped it.
Had something similar done for my Austin crank by the same people where they just increased the weighting when they made this crank last year. The difference in the engine's smoothness at 5000+ revs is really marked.
Hope they know what they are doing - remember reading a report on aftermarket "improved" cranks for Rover K-series cranks that were out of balance and much much worse than OEM - at time I was working for a company suppying machinery to clean the OEM cranks during manufacture.
Happy not to have the patina (and the ovality) on the front main. That "missing" step on the front is because the original belt pulley was a press fit, and that was all that holds the helical timing gear in place. The new crank is drilled and tapped 7/16 UNF at the front so that a cap screw can retain both.
The flywheel flange is much deeper than the original so that a lip seal can run against the diameter. For that reason, the tapped flywheel holes are blind. The original motor's main bearings were splash fed, so there was no oil seal at the rear. The big ends had dippers that scooped up oil at the bottom of the stroke. That's OK when the motor has peak power (according to the manufacturer) developed @ 2800 RPM; I'm not wishing to turn an old touring car into a dicer, but it is going to have to be able to cruise at motorway slow lane speed to be safe in today's road conditions. The crank has been drilled for pressure feed and has narrower big end journals to accept "off the peg" EN19 rods with shell bearings rather than the original white metalled rods which were well known to fail on standard motors in period. I'm sure purists will decry these and other discreet mods I'm making to the car, but in my experience, purists don't use their old cars very much.
love it......
Had a place in Longbeach, Calif that made a V16 crank for a place where I worked.......from billet steel.....the old 1 broke in 1/2.......
when I took the old crank the w/shop was amazing......the guy that owned the place said it was a "BIT SMALLER" than what they normally work on....
out of interest that was nearly 45 years ago and the cost was $1,200.......soooooo cheap.......
hope we get to see the finished car.......
have fun