What do you guys think about this.......

[doonjumper]

I was looking for an underdrive pulley set up and came across this website. It claims that they took a motor and put it on a dyno with it's original stock pully system. Then took the belt off and only gained 3 hp and the articles claims that they "rounded up" to 3 hp. If this is true then where are the manufactures getting the whole " gain 15 hp by using an under drive system". Here is the site. http://www.teamscr.com/pulleys.htm Scroll to the bottom of the page and read the "Horsepower story" Is the whole underdrive system just a bunch of crapola or am i missing something?

 

[CDA 455]

I was looking for an underdrive pulley set up and came across this website. It claims that they took a motor and put it on a dyno with it's original stock pully system. Then took the belt off and only gained 3 hp and the articles claims that they "rounded up" to 3 hp. If this is true then where are the manufactures getting the whole " gain 15 hp by using an under drive system". Here is the site. http://www.teamscr.com/pulleys.htm Is the whole underdrive system just a bunch of crapola? Am i missing something?

It's called exaggerating their claims.

By using a super light-weight, over-sized pulley set up; one can gain some HP.

How much? It varies from set up to set up.

Remember going to electric fan(s) and doing away with the clutch fan thereby gaining more HP? Same principle.

Less drag on the pulley system equals more HP to the rear.

 

[resurrected_jimmy]

the problem with underdrive pulleys is that they make your accessories less efficient, less power assist on the steering pump, not as much juice being put out by the alternator, and your water pump turns slower if you change them all out

 

[doonjumper]

It's called exaggerating their claims.

By using a super light-weight, over-sized pulley set up; one can gain some HP.

How much? It varies from set up to set up.

Remember going to electric fan(s) and doing away with the clutch fan thereby gaining more HP? Same principle.

Less drag on the pulley system equals more HP to the rear.

Yeah I get that, but thats a different story. You are actually eliminating a huge weight on the front of your engine. They are talking about just replacing pullyes. Go raiders!

 

[CDA 455]

Yeah I get that, but thats a different story. You are actually eliminating a huge weight on the front of your engine. They are talking about just replacing pullyes. Go raiders!

I edited/updated my post !

 

[CDA 455]

the problem with underdrive pulleys is that they make your accessories less efficient, less power assist on the steering pump, not as much juice being put out by the alternator, and your water pump turns slower if you change them all out

Yep, excellent point!

Getting more HP from the pulley set up is more for Street-driven drag racers.

 

[DesertDueler2]

All underdrive pulleys normally do is cause you car to overheat(well here in AZ at least). They also slow your alt down, so if you are running a bunch of lights or a big stereo than thats not good either. Your biggest way to free up power is electric fan and waterpump. I gained 20 rear wheel hp on my race car by doing this.(tested on a mustang II dyno). I was running the big 7 blade fan and the factory HD fan clutch so yours may be a little less but you get the point. Spend the money on at least the fan if thats the route you want to go. Or put nitrous on it and be set

Dan