If anyone is interested I found that 91 and 92 Caprice taxis and police cars use a smaller diameter serpentine water pump pulley for additinonal cooling. It has a stamped series 10100791ACB
and E1 S1

Currently I'm using a march 2 piece billet steel underdrive pulley kit. Although I'm aware that any gains from the underdrive pulleys may be lost but I have no choice since I can't find a stock crank pulley for cheap


Anyway, I'll guess the caprice waterpump pulley is about 15% overdriven. Anyone have a more accurate percentage? When I find a proper belt size I'll keep you all updated.


Ed

 

im in the same boat dude. i have a march crank pulley i want to put on my car again, but the car starts to over heat cuz it doesnt spin the water pump fast enough - i need to find an overdriven water pump pulley but i havn't found one yet =\ march doesn't sell them, and i dont know anyone who does... i guess ill look for a 91-92 caprice in the junk yard or something lol

 

well I just got a belt and you'll have to route it as 89-92 instead of 88



Kelly Springfield 915k6

or

Dayco 5060915


I haven't come up with a GM part # for the small caprice waterpump pulley but I'll let you know.

BTW, the diameter of the caprice pulley is about 5 1/2 " versus the camaro's stock 5 3/4"

 

you know what sucks.,...i pulled a 91 caprice L03 mechanical water pump off about a week ago and tossed it aside in a jnk yard......

oh the irony...ill go back and see if i can pick it up if yall want

 

i wonder how much they'd charge me at the junk yard for just the pulley?

 

Why would changing to a smaller water pump pulley require changing the belt routing to the 1988 routing instead of the 89-92 routing?

 

maybe because it has too much slack in the belt/tensioner? i dunno...

id just go get a shorter belt.....what i did for my smog pump....just got crafty and figured out a new way to route it

 

Using the Smog Pump delete pulley lets you use the stock belt, avoid excessive belt flex, and retain the two bolts holding the belt support bracket to the block. If you run high rpms, you need this. But I'd still like to know the difference between the two serpentine belt routings, if anyone knows ... please.

 

I apologize for responding late people.

I've made a correction from a earlier post.

For the march 2 piece billet steel crank and Alternator

USE kelly springfield 915K6 or Dayco 5060915 They are the same size belt as a 2002-04 Chevy Trailblazer or GMC Envoy

The one I specified earlier (910k6) is a little too tight . I had to go back to the store and exchange it. Wanted it just right you know.

Route the belt from the smog pump, around the waterpump pulley and then around the crank to the powersteering

Also, for those who want to use the caprice water pump pulley with their stock crank and alternator pulleys, just purchase the belt used in the caprice (specify standard alternator)

 

this is great to use on a stock setup. mine cools ALOT better @ idle with the a/c on than it used to with the stock sized pulley. used to heat up @ idle. this on a completely stock 88', L98 serpentine setup.

any 91-92 caprice (with the new, rounder, & larger, body style caprice will have the same pulley.)

i have verified this by checking many patrol and non-patrol caprices @ pick-n-pull.

thanks for the heads up.

 

on e-bay there is a corvette water pump pulley for serpentine what has a 5 1/2 inch diameter pulley would that work. the item number is 7906424394

 

also when being used, on a completely stock setup (air pump still working), routed the 89'-92' way i used a 940K6 belt.

 

what if using a smog pump delete pulley and A/C delete pulley with a caprice water pump pulley, what way do you need to route the belt and what belt do you need