I'm thinking of installing a set of underdrive pullies on my 85 GT. Are they everything they are advertised? And if I am using a high capacity water pump, will I be defeating its purpose by slowing it down? Any opinion would be appreciated.

 

Not worth them! When I bought my 91, the guy had them on there, i pulled them off right away, the 3 hp is NOT worth the dim lights and warmer than normal temps IMO!

 

use a cooler stat and a flex light fan then a light weight PA hi po alternator use a respectable full pulley set not jus the crank pulley
and they can be good for as much as 2 tents useing the properset also use billet or alum pullies not shizzy steel
remember one bolt on is not going to make a car that muh faster you have to build the entire package wich is what people forget pullies are worth less on a stock 210hp 302
but said engine with heads cam intake exhaust and a decent carb really benifits from such

 

yeah i picked up some on my 86. dont know if i picked up much power but with the lighter aluminum(sp) pullies the engine reved noticibly quicker. had a high flow W/P and alternator. so never had a problem with dim lights or overheating

 

Yea you need the right ones don't want them to under check Steeda or Unorthodox Racing. Light weight helps also. :geek:

 

i had march aluminum pullies. great quality. much lighter than the stock set