Flywheel on a b

Its a solid chunk of steel that has holes drilled in it for balancing.  I'm not sure what internal vs external balanced means.  The crank has no counterweights on it that I'm aware of.  Turning 1800 or 2,000 no load, I'm not sure it's as critical as the 383 stroker pages I read trying to figure out what the terms mean.

AaronSEIA

Never saw a 4.3L V6 with a big weight on one side. The 4.3L Chevy V6 is internally balanced just like a sbc. They're basically a 350 V8 with two cylinders missing off the rear. I had a Carbureted 1985 vintage 4.3 in my 29 Model A P/U, I have a 92' vintage 4.3 in my 31' Model A Vicky, and a 97' vintage counter balanced shaft Vortec 4.3 in my 67' Nova Wagon. The Vortec is still internally balanced between the crank and the hamonic balancer. The balance shaft is a weighted shaft located in the lifter valley of the engine and spins in the opposite direction of the crankshaft to offset the vibrations that are created by the inconsistant power stroke angles over 360 degrees of crank rotation. Doesn't have anything to do with the crank balancing.  They all can use a 6" sbc 350 harmonic balancer on them. I believe the counter balance shaft engines started around 1995-on. What's cool about the 4.3 is you can use all sbc parts on the front of it. That's what I have on all my cars. Pulleys, pumps, balancers etc.   HTH

Steve@B&B

Musta' read your post wrong. I thought you were talking about the crankshaft having a weight on one side. You're refering to the flywheel having a weight. Thats a flywheel balance weight. I have those on all my flywheels also. Still has nothing to do with the crankshaft and harmonic balancer.  All Chevy flexplates line up one way on the crank. Some cranks on the older sbc's had a dowl pin. Install it, slide the torque converter up to it and bolt it up. I've been using the same flywheels for years with my 4.3's. They work fine on my vehicles.  Should be a nice install in your B. I like the idea!  I'm a B guy, and a 4.3 guy. Go for it!!

Steve@B&B

Ahhh! But the 400 small block with its 4 1/8" bore and special counterbalanced crank had a special stepped harmonic balancer that was ONLY used for the 400 sb.  Now your talking peaches from apples.  Not sure about the BBC. I wasn't a BB guy. If you're going to use the B flywheel, then I would have it balanced as an assy with the crankshaft rods, pistons, & balancer. If you're going to use the flexplate with an Auto Trans behind it, then you wouldn't have to do anything. I have plans on installing a Mercruiser 160 4 cylinder in my WC with A/T after I retire when I have more time to "play"....  Good luck and have fun doing that install!!

Steve@B&B