Crank ccw design, and balancing article from Engine Builder

Published March 25th, there is a very informative article on CCW crank design, and proper methods for balancing race engines. It seems the subjects are much more complex than we may think.
Things like correct metal removal for balancing (not drilling!) and proper counter weight location and design . It got my attention, since i am now touching the 1,000 hp range, and stresses get worse the more power we make.
So IMHO no longer will just any crank will get the nod.
The question becomes, does my choice of crank maker employ rhe latest design, to minimize frequency issues, balance and stress issues? Every power level will have a little dfferent quality requirement. And real high horsepower and high rpm motors will want much better cranks in ways we may not be aware of.

All I am going to say is all of mine are billets. Two Bryants and one Moldex. in the past I have run Crowers with great results as well. IMO I cannot think of any company that produces a CCW that is not doing it "correctly". We run a Billet Scat in the Vette and it routinely seen 10,500+ RPM. The crank bearings in it have been there since 2009.

Good info, Al.Thanks. i was surprised to read what was said about the effects of drilling counter weights for balancing. At a certain stress level and rpm point it can cause frequency or vibration issues thatcan't be resolved, seriously eeducing the life of a motor. I assume guys who run comp eliminater level motors experiance this.

I would not be the least bit surprised if someone messed up a good crank with a crappy balancing job. I bought a car that had an engine from a big name Mopar engine builder and the crank had 12 slugs of Mallory in it. Needless to say its sitting on a shelf.

I think anything that is going to regularly see north of 8500rpm needs a billet crank, and the ccw design certainly adds stability. Nipping the 8k chip once in a rare while is one thing, routinely shifting and holding through the traps at rpm above that demands an investment in the crank department if you want any chance at long term reliability. Just my two cents

That, and stroke. I had a chance to buy a 4.75 inch stroke non CCW crank, and passed on it after hearing that they didn't fair well at high rpm/high horsepower. That is also the reason I have a nice 4.560 stroke non ccw crank on the shelf. Someday it will make a great torque motor combo, rpm of 6500 or less? That and my 440-1 heads ought to generate some decent power down low with 580 cubes.

Not the level you are discussing, but I like the way the shop that balanced my Callies 4.500" stroke crank did it. Less than 7500 rpm.

The shop said they turned the crankshaft counterweights a lot, so they only have small drill holes for final balance.
They didn’t have to touch the 4 inner counterweights (3.79” radius). They reduced the diameter of the front and rear counterweights about 1/4”; and then only needed one drill hole in the rear counterweight to achieve final balance. About 0.93” dia x 0.66” deep to the tip. They used a drill with a large radius, almost a ball end. They must have gone between the lathe and the balancer a few times to do this. IMO, this leaves more counterweight toward the center of the crank; reducing stress. From my estimates, the Callies crank was over 2500 grams before balancing.


572 CID B1 Build - Part 3. Crank Balance

I bought a old used forged steel KB Top Fuel fully counterweighted crank that had 4 cracks in it and sent it to David at marine Crankshaft CO in SO CA to fix it
I took it to Summers Machine in Battleground, WA last year along with Scat H beam steel rods Mopar size rod journals rated at 1000+HP, JE pistons and it ended up costing me a tiny bit under $1800.00 for the balancing, they said it took a bunch of heavy metal to balance it
I'll buy new stroker cranks from now on