I am wanting to know what the max recomended HP rating is for the following drives:

A standard B1
A B1 XZ
A B1 XR

I have about 625-650 HP per side, and have B1 XZ's..... I'm concerned. How concerned would you be? Thanks.

I'd run what you got.

XR gear quality over the last few years
has been marginal....I've went through
4 or 5 sets in the last 4 years with
less power than you're running, and on a much
lighter boat.

I've had the teeth chunk out a couple times,
had a tooth break off once, trashing the
whole upper, and had a gear crack and
split the cone off of the gear on the same
drive I replaced the complete upper on.

you should look into konrads with a 38 theres room for trannys or do the ace package and you don't move the motors.

I still like B-Max a direct bolt on and alot cheaper. I run 720 HP with no problems. I could break a Bravo by hitting the trim button. Kept spares. It got stupid.

I think you'll be fine with the XZ's as long as you're easy coming on plane and good on the sticks in LOTO wash machine. Frequent lube changes(25hrs) will help and will also catch any possible problems before they become major problems.

BTW, 600sc's were mated to regular Bravos before the XZ/XR's.

I ran 725 hp on XZs for three years with no problems, I had drive showers and took it easy getting on plane.