What do you guys use for a water pump pully when you use the sbc 8" balancer on a Chevy 250 6cyl? Looks like with the larger balancer it will interfere with the WP pully. I want to be sure and have what i need before having machine work done on the balancer..Jerry

I would think you need a smaller than stock size pulley for the W.P.
As a guess, stock size damper is 6.750" you are going to an 8" so, you would need to go down to a size of approx of 1.25" smaller on your W.P. pulley,note: this will speed up your W.P & all your accessories will spin faster also because of the 8" damper.
It won't be 8." exactly because you are going to machine grooves into the damper,so , say, 7.75" - 7.50" or so.

If you do not want to go to the trouble of changing too much, I would think a S.B.C., 6.750" damper will still work, & better than the stock L6 damper, & this way, you would not have to change anything else.

I personnally have not used one, but I would use a SBC one over a stock L6 one.
I never ever had any stock L6 dampers worth a BEEP, going over about 5000 RPM.

If you have an 8" damper already, as a close guess, I think you would need a W.P pulley about 5" - 5.5" OD to clear the 8" damper

MBHD

Thanks,..just about what i had worked out in my measurements. I will just have to start sorting through pulleys to find one that size that will line up with everything..Was in hope someone here had already done all the leg work !!! Getting LAZY in my old age.

I'm using a Streetdampr on my stroker. I shortened the hub to tuck it close to the timing cover. Next time I'll bore out the crank gear instead.

Another way: I'm using a single groove sheave bolted directly on the front face of the damper and an altered water pump sheave to line up. This requires work on accessory brackets to get everything to line up and it also decreases clearance to the radiator. It's not together but I can take a photo of the pieces if you want. I think the sheave was originally a '60s BBC power steering crank sheave. It's flat with no dish.

I personally would like to see pics of that.

I posted photos in my Nova project thread.