skatepony

hey guys......i bought a set of billet under drive pullies from cj pony parts at a swap meet near me probably about 2 years ago and didnt put them on my car(88 gt) until last week.....anyway now after i put them on i havent really felt so much of a differenece, i havent brought it to the track yet though, the other day i measured them for the hell of it and the water pump and harmonic balencer pullies are the same size and the alternator is actualyl bigger then stock...did i get ripped off or is this normal?????

impure

i think you got ripped dude. i dont know cause i dont know much about the underdrive pulleys. plus you should be able to feel the hp and torque diff. but its the same as a bike sproket and a chain i would think. i mean the smaller sproket the less harder it is to turn and the bigger the sproket the harder you know. maybe i am retarded but thats what i would think

clienterror

You got ripped, the one at the crank should be LARGER and the one for the alt and water pump should be SMALLER.

impure

yup its for sure. i just talked to my dad and he said that the crank pulley should be thirty percent smaller than your waterpump pulley

clienterror

You sure? If the crank was smaller than stock it would make anything on the accessories belt go faster causing more parasitic drag on the engine. If you got a bigger crank pully it would make them rotate slower lowering the parasitic drag.

Then you want a smaller on the alt/water pump so it over drives them which makes it back to stock rotation because your slowing them down because they crank pully slowed everything down.

92hatchLX

Can you really even tell a difference with u/d pullies anyways?

Blue Oval

the alt and water pump should be bigger, and the crank should be smaller than stock. since the alt (and water pump) pulley is bigger, it turns the alternator less, and the smaller crank pulley turns the belt slower

nitr0x99

wow every post so far is like completely contradictory to the post before it [:@]

impure

oops sorry i f$@#ed up. ya i meant that the water pump should be 30 percent smaller than the crank pulley. sorry for the confusion

Blue Oval

yea but i think mine is the right one