what belt to use with underdrive pulley?

[jgx421]

Ok, I need to understand a couple things. First, electric fans. I want to know if you need a different belt when you get electric fans and how to take off the old clutch fan. Next, underdrive pulleys. If I were to put pulleys on my 4.3 what belt do I use? And if I were to have both e-fans and pulleys, what kind of belt would I use then? I'm confused about how that works so any info would be helpful.:thumbup_1

[trusconi]

e fans you leave the pulley because you still need to turn the water pump.

[BigMoney]

Yeah e-fans don't have any effect on your belt size. As far as a belt for the pulleys goes, when I had the March Performance underdrives (never installed them, so I can''t know for sure) It said to use a 91" belt. Some folks say a 91" belt is too small and you need a 92" belt. Other folks have been able to find a 91.5" belt, and that seems to work the best.

[russ_2004_85]

Yea the belt has to stay for the water pump. Now i got the sts pulleys. And from what I understand gator belts are the best. Only good year shop will havethem. Check sts.com. See if the belt size is there. I've had mne on for 2 years. No problems

[87wildside]

The pulleys should tell you what belt or how much shorter.

[12sws27]

The instructions on a March pulley kit will suggest a size. If it isn't quite right you'll have to return it for a size smaller/larger. I have noticed that there is some pulley that must be a little bigger on my 98 then on my 00. When I put my S/C (requires different size belt) on the 00 I had problems with the belt provided in the blower kit. It was a bit to big. So I bought a smaller belt. Later on when I got my 98 and put the S/C on it, I couldn't get the smaller belt on it. So still having the belt that came with my Wynjammer I tried it. It fit perfectly on my 98 and didn't slip like it did when I used that same size on my 00. So I assume that somewhere (99 or 00?) GM changed the size on one of the pulleys. My guees is it's either the Idler or tensioner pulley. Anyways, I figured I just put there out there.

[jgx421]

Alright fellas, thanks for clearing this up for me. I was wanting to switch to E fans for this HOT south Texas heat. It's also my understanding that changing to e fans will free up a few ponies, which sounds good to me, so this looks to be my next upgrade. Again, thanks fo sharing your useful knowledge with me.