I have run several of these with ZERO problems.
I have never actually heard of anyone breaking one.
Yes there have been failures where people have welded the flange to the T location, but that is a "unrelated" issue and good solutions exist to prevent that.
Your stories would be appreciated.
Les:
the only failures i am aware of were due to a poor weld on rear flange ...your process of shrink fitting the flange should eliminate this issue ...please post pictures and an explanation of your process ...you had emailed these to me several years ago ...always an optimist...gene french
Les:
the only failures i am aware of were due to a poor weld of the rear flange ...your process of shrink fitting should eliminate this problem ...please post pictures and an explanation of your process ...you had sent me pictures several years ago ...always an optimist...gene french
what happened ! twice ?
Gene
Yes my shrink fit process has proven trouble free. The other option is to move the block the needed 5/8" forward on the pan. Not a terribly difficult option either
So it appears that a properly installed A crank might be fairly reliable
Les,
The only breaks I've heard of are at the welds, as others have stated. I've always wondered though, why does Scat even bother to make a Model A crank if they're so indestructible?
I've run a full length "A" crank in my Racer (see profile) with a BB RAJO for over 20+ years & have several thousand pretty snappy miles on her - no problems here !
Jerry
I can understand the attraction of having a counterweighted version. I've bolted on counterweights to one. I've also installed a Model C crank turned to A size (it was REALLY rusty but cleaned up nicely at the smaller size) with the integral counterweights
That's true Les.
Les,
Several years ago, some one at the San Diego Big 3 swap meet had in the back of a P/U a T engine with the pan removed having a broken model A crankshaft that did not fail at the flange. Both Art Wilson and I seen it. Art may remember more details where it broke...think it was between #1 & 2 Throw. That's the only A crank that I have seen that broke in another area than the flange.
I have had a welded flange fail in my T speedster, but In all fairness, a weld that crappy would have broke by lookin at it funny. I have also seen a flange come off in a stock A motor before.
The only non flange failures have been an A ground to T journal size... Broke at a rod journal. And a full length A in a '27 Chevy 4 hill climber... Broke at a rod journal... In all fairness this crank earned the break!! There is a limit to every design, and this motor was beyond it!! 528 feet of pavement on a 10 percent grade... 85 mph!! If I had to estimate hp, I'd say bout 150.
For the most part if the weld is done right, there is nothing to worry about. I push my car hard, and have for years. And so have many others I know. I won't be trading in my welded crank any time soon, and will probably shorten, weld, and install many more.
Kevin
Thank you for the good complete information. I had a welded one that ran for a number of years. It pulled hard to 4200-4500 rpm. The car was capable of 100 mph. I sold the car and heard ( but can't verify) that the weld eventually broke. I've now adopted a method of shrink/taper fit the hub with no failures
Again thanks for the response