Underdrive Pullies?
Thread Starter
Melting Slicks
Joined: Nov 2001
Posts: 2,793
Likes: 58
From: God's Country The Old Dominion
Underdrive Pullies?
Do underdrive pullies give any gains? Are they hard on the engine?(mine has 90K) If they are a decent mod who makes a good set? How hard are they to install and how expensive? :chevy
Team Owner
Joined: Dec 2000
Posts: 90,675
Likes: 304
From: SE NY
Cruise-In II Veteran
Re: Underdrive Pullies? (Too Slow '90)
With only the underdrive crank pulley installed I noticed the engine revs up faster but saw no increase in trap speed due to other issues at the time. With accessories on at night at idle (700rpm) I only see about 11.5 Vdc. You've got mail on the HP to expect.
It's actually easier on the engine with less parasitic drag.
March makes a 3-piece pulley set, though I've not yet installed the alt overdrive pulley. Cost was about $125.
The crank pulley is easy to install; the alt pulley requires an impact wrench. You will also require a shorter serpentine belt.
It's actually easier on the engine with less parasitic drag.
March makes a 3-piece pulley set, though I've not yet installed the alt overdrive pulley. Cost was about $125.
The crank pulley is easy to install; the alt pulley requires an impact wrench. You will also require a shorter serpentine belt.
Safety Car
Joined: Jun 2000
Posts: 4,870
Likes: 25
From: Long Island, NY
Re: Underdrive Pullies? (Too Slow '90)
The pullies are not hard on the motor at all.
The crank underdrive pulley will help your ET's ever so slightly.
The bad point is that you will have a lower battary voltage at idle.
Vic
The crank underdrive pulley will help your ET's ever so slightly.
The bad point is that you will have a lower battary voltage at idle.
Vic
Burning Brakes
Joined: Dec 1999
Posts: 765
Likes: 11
Cruise-In I Veteran
Re: Underdrive Pullies? (Vic'89)
The bad point is that you will have a lower battary voltage at idle.
Vic
Vic
[Modified by lowflyer, 1:14 PM 1/6/2002]
