Under-Drive Pully or Not?????

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Nov 23, 2007 | 05:18 PM

#21

Mike Ward

Race Director

Joined: Jul 2001

Posts: 15,892

Likes: 42

Quote:

Originally Posted by gkull

Ya, maybe in a stock low rpm motor. Once you start exceeding 6000 rpm or in my case 7000 rpm stock heavy clutch fans are ineffective, hp robbing, and probably down right dangerous

A stock clutch has no idea what HP your motor makes or what the red line is, nor does it matter. They came as standard equipment on LT1 and Z28 motors which rev as high as yours.

The fan/clutch assembly absorbs less than 1 HP when it is freewheeling. Most modern types unlock at speeds over 2500 rpm.

If your engine is revving over 2500 RPM and consistently needs benefit of a fan, you have other cooling problems that need attention.

Dec 13, 2007 | 06:45 AM

#22

Fonz69

Pro

Joined: Jun 2007

Posts: 688

Likes: 1

From: Stevens Point WI

I am looking for a set of pulleys and brackets for my 69 vette

Motor BB 540 Dart

Have power steering

Have dewitts radiator with dual fans

Will be using hooker side exhaust

Anyone sell a kit?

Anyone have any used complete setups?

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