speed-up water pump(smaller pulley) whos got these?

[cadipacer]

Got the gas flow solved thanks to everybodys help!!!

NOW focusing on the cooling,,, I want to increase low RPM speed
of the water pump.. maybe it will aid in the running a bit cooler at the idle and at red lights/stops. Has anybody done this with proven results, if so what application was it taken from in the CAD -line,,, or used aftermarket items..? Is this a "AL " item?

[lux hauler]

You can either get a FlowKooler water pump or FlowKooler also makes a disk that rivets to the impeller of a standard pump. AL sells the FlowKooler pumps......I'm not sure if he has the disks or not. If he doesn't, Summit does.

[Al from MTS]

I'm not aware of any aftermarket reduction pulleys for the Cad.
You can find what your looking for used. Cad's that had clutch fans had the factory HD cooling option. The waterpump pulley is smaller and the crank pulley larger to speed up the pump. Was fairly common to find this stuff on the 1977-1979 425's.
If the engine has a direct drive fan it won't have that pulley set.

[STDog]

Cad's that had clutch fans had the factory HD cooling option. The waterpump pulley is smaller and the crank pulley larger to speed up the pump. Was fairly common to find this stuff on the 1977-1979 425's.
If the engine has a direct drive fan it won't have that pulley set.

So can you just put the smaller pulley (from a clutch fan engine) on the pump keeping the original crank pulley( from a non-clutch fan)?
Would the fan& clutch be needed, or is the non-clutch fan ok?
Any I dea how much shorter the belt would need to be in this setup?

[cadipacer]

Thanks again for the advise,,, and tips,, Now this weekend I'll be a hunting for those Caddys /425 w/ clutch fans / heavy duty cooling..
IF any body has a set ,, let me know.. Ill post a ad as well

[Caddycarlo]

what makes you think speeding up the water pump means more cooling?

[cadipacer]

The only real reason to speed up pump.. is to duplicate the Factory idea of heavy duty cooling in terms of max movement of water IF indeed would /could be a small factor in the hotter engine at a idle(heat soaked), I have a alum rad now with 2 - 10" puller fans(2500cfm) I'm installing a 16" pusher fan now, along with above idea,, and notching two- 2"x9" slots in the underside of hood allowing heat to escape at the cowl, plus staggering the fans I have now to better cool all the horizontal cores not just the same ones twice, so I'm looking at ALL aspects to run cooler..
Thanks PHil,,, ( my car is a low buck ride) the pics you sent are very nice I only see this nice of a set up at shows!!!

[curtis73]

what makes you think speeding up the water pump means more cooling?

It doesn't necessarily. You have to have the right speed and caddys do tend to be a little slow on the pump. More cooling can happen by decreasing the pump pulley size by about 20%. Any more than that is probably too much.

GM designed them like all of their other pulley ratios but since Caddys are so low-revving, the RPM range of the pump is a tad slow. The same problem exists with Olds 307s from the 70s and 80s.