Log in

View Full Version : Underdrive Pulley?


alamantia
02-03-2008, 10:03 AM
In researching a cam for my car it was mentioned to me that since the crank pulley must be removed its a good idea to purchase an underdrive pulley. Has any experianced and charging or cooling issues using an underdrive pulley in their LSX vehical? I would imagine on a hot day in traffic there may be some overheating issues. Has anyone had any problems with this or are LSX vehicals void of thses issues?

WildBillyT
02-03-2008, 10:13 AM
Personally I think that they aren't worth it in most cases. There are better ways to make power.

edpontiac91
02-03-2008, 10:43 AM
I have one on my 350 1991 Formula. It's one those things that is supposed to give you an EXTRA 5 hp. Yeah right. If I really believed ALL the claims for every item that I bolted onto my engine I should have 538 hp by now! :shock: The car runs fine, no overheating or charging issues, but I would have to assume that you should have a GOOD battery to start off with, and not plan to have six 500 amp speakers and your A/C going full blast in a 2 hour traffic jam.

98tadriver
02-03-2008, 11:17 AM
i had the UD pulley on my car, it caused no issues whatsoever.

ins0mnia24
02-03-2008, 11:41 AM
I changed mine because at W.o.t. my belt would slip on occassion which seems to be common on LS-1's
I did my research and got a Powerbond 25% u.d. pulley, it is SFI approved and they also happen to be the supplier for SLP except that they sell for alot cheaper under the Powerbond name
I daily drive mine and never had a problem with anything

jeff wilson
02-03-2008, 03:40 PM
theres no downside, just alot of money... ive got an ASP

ar0ck
02-03-2008, 06:04 PM
I've had one on my Lt1 for a few years and I noticed power surges at idle with the stereo on. I might have had a bad battery but I did notice I had charging issues, and at the time I was daily driving.

Now with the new motor I have a Fluidamper Crank Pulley with a new battery and I no longer have any surging issues or un-explained power loss!

Mike Something
02-04-2008, 02:03 AM
Have a 25% ASP on my LS1, I think it let's my car rev up alil quicker, I wouldn't boast about any big HP gains tho. No problems at all w/ charging/cooling. I could only see it being a problem if you have a big audio system in your car.

JSPERFORMANCE
02-04-2008, 07:12 AM
it is worth it just to have a better SFI approve dampner..

01SS
02-04-2008, 07:05 PM
When i got my new cam i did the underdrive pulley installed at the same time. I have not had any overheating problems in traffic or otherwise. I was also told that the UD pulley wont really make more horsepower but drop about a tenth of quarter time. Not sure how true that is because I also am never going to this mechanic ever again.