Cobra4B

I know many jump on them when adding a cam, but how much do they slow down the water pump and is this a bad thig on a tracked car?

Or, does the pump still have plenty of flow?

Any tuners/racers care to comment [cough]Lou [/cough]


LGM (added if lou searches)

Gary2KC5

More HP good for track car, no problemo with coolant pump.

VetteDrmr

Actually, I thought underdrive pulleys were best for a track car. Kept revs down on power steer and water pumps, alternators, etc. I could even see where too high revs could cause a WP to start cavitating.

No down side that I can see.

Have a good one,
Mike

LG Motorsports

We have been using the UD Pulleys since the LT1 cars in the early nineties. In fact, in 93, the first year we ran the New(new back then) Fourth Gen Camaro, we could not finish a race weekend without changing the power steering pump because they ran too fast and burned up.
So we came up with our own UD pulley for the Camaro (quickly copied) and that solved the problem. We kept it hidden during 93 so our competitors would burn pumps up every weekend.

On the Corvettes it is not as bad but it is still desirable to slow the pump and alt down. And there seems to be no down side even when street driving with all the bells and whistles blowing.

So from our perspective, the UD pullies are a good thing for street or track.

Also just to put it into perspective, we slow our World Challenge Water pump down even further than any UD pulley would. At 7400 rpms the water pump would cavitate for sure if it was not slowed down.

Thanks
Lou G