jerm4472

hey guys, im a ls1 rookie and im learnin the ropes. Could someone explain to me how an underdrive pulley works and gives more power? thanks

MX6.0

Belt driven accessories take power to turn. By decreasing the diameter of the crank pulley 25% you are effectively reducing the amount of times it has to turn the accessories per revolution of the engine. Doesn't make a huge difference in power but it all adds up.

SippiSpeedhawk

iTrader: (21)

It's not worth it to do it alone. The only reason I decided to use one is because the motor was already out and apart.

ssdeuce74

iTrader: (2)

they had a deal goin for 210 pulley belts and new bolt i did it in 30 mins and car was 2mph and 1.5 tenths faster in the 1/4 and 1.5 mpg gain. i got the powerbond i believe, if you can get the RIGHT PULLER and do it yourselve it's absolutely worth it. contact Scoggin Dickey Parts Center thats where i got it from. this is on a camaro don't know what platform your got.

mike c.

iTrader: (1)

It is worth it alone. We installed one at the track and did back to back runs some years ago. the car gained just over a tenth. use the asp pulley. it's lighter,great quality and i had one on my ls1 and 402ci with no issues ever. i have ran close to 9's on one with no issues and will run 9's when i get back to the track...i hope. my bud has ran one on his ls1 and 383ci with no issues ever. If it's out of stock,call asp them selves and wait for it. The power bond is easier to get,i got one and sent it back and waited for the asp to get in stock.

vettenuts

iTrader: (4)

I personally would not use the ASP. There have been a number of timing chain failures linked to the ASP. Weight is not the critical factor and you have the remember that first and foremost this is a harmonic damper.

38DD2436

Summit racing now carries ATI UDP with air conditioning. $437.

1badeagle

iTrader: (9)

I run the ASP on my car and 0 problems so far.

Undertow74

iTrader: (45)

Same here, ASP pulley with ARP crank bolt.....easy install 0 issues. Now, when i get my new setup i Might drop the cash on a ATI superdamper, but thats alota cash for a pulley

Stippy17

iTrader: (5)

I'm running an ASP ud pulley with no problems. I haven't had the car back at the track to see how well it helped, but it should drop about a tenth in the 1/4.

vettenuts

iTrader: (4)

There is a strong correlation between the ASP and broken timing chains. Here is a link to one, and you will see Katech is noting the same issue. Not trying to dig at anyone, just want to pass on information so you guys can make a decision on your component as I would hate to see you have major issues. (Note that linke below is one of a number of threads on the subject and that Eric D who posted in the thread also works for GM).

Link