underdrive pulleys
Drifting
Joined: May 2003
Posts: 1,529
Likes: 2
From: Lakeland FL
I have had one for at least 5 years. The only problem is that the voltage being charged under load is a little lower but that is about it. It should get you a few extra HP so I say it's worth it
if you have to do it anyway.
I changed mine out when I installed the cam it was a no brainer since the whole front end was apart anyway
I can't remember what brand mine is but I think they are all about the same check around.
if you have to do it anyway.I changed mine out when I installed the cam it was a no brainer since the whole front end was apart anyway
I can't remember what brand mine is but I think they are all about the same check around.
Thread Starter
Drifting
Joined: Aug 2007
Posts: 1,495
Likes: 0
From: Homer Glen IL
I have had one for at least 5 years. The only problem is that the voltage being charged under load is a little lower but that is about it. It should get you a few extra HP so I say it's worth it if you have to do it anyway.
I changed mine out when I installed the cam it was a no brainer since the whole front end was apart anyway
I can't remember what brand mine is but I think they are all about the same check around.
if you have to do it anyway.I changed mine out when I installed the cam it was a no brainer since the whole front end was apart anyway
I can't remember what brand mine is but I think they are all about the same check around.
Melting Slicks
Joined: Aug 2000
Posts: 2,900
Likes: 2
From: Green Cove Springs FL
ASP here, I noticed the car seemed to rev a bit quicker and maybe a bit of gained power. Nothing I could feel on the butt dyno though.
The stock harmonic balancer does have balancing weights on it, no matter what people or the manual states. GM says each part (flywheel, crank, harmonic balancer) is supposed to be "zero balanced".
I've only put maybe 6k miles on my car since changing mine. There have been reports of people shredding bearings after putting some hard miles on with one of these, so just be aware of that. If you search deep enough on this site and a certain tech forum you can find those posts; however, I imagine it's a very small percentage.
There's also ATI's super damper, but I'm not sure if it's an underdrive or not.
HTH
The stock harmonic balancer does have balancing weights on it, no matter what people or the manual states. GM says each part (flywheel, crank, harmonic balancer) is supposed to be "zero balanced".
I've only put maybe 6k miles on my car since changing mine. There have been reports of people shredding bearings after putting some hard miles on with one of these, so just be aware of that. If you search deep enough on this site and a certain tech forum you can find those posts; however, I imagine it's a very small percentage.
There's also ATI's super damper, but I'm not sure if it's an underdrive or not.
HTH
Thread Starter
Drifting
Joined: Aug 2007
Posts: 1,495
Likes: 0
From: Homer Glen IL
ASP here, I noticed the car seemed to rev a bit quicker and maybe a bit of gained power. Nothing I could feel on the butt dyno though.
The stock harmonic balancer does have balancing weights on it, no matter what people or the manual states. GM says each part (flywheel, crank, harmonic balancer) is supposed to be "zero balanced".
I've only put maybe 6k miles on my car since changing mine. There have been reports of people shredding bearings after putting some hard miles on with one of these, so just be aware of that. If you search deep enough on this site and a certain tech forum you can find those posts; however, I imagine it's a very small percentage.
There's also ATI's super damper, but I'm not sure if it's an underdrive or not.
HTH
The stock harmonic balancer does have balancing weights on it, no matter what people or the manual states. GM says each part (flywheel, crank, harmonic balancer) is supposed to be "zero balanced".
I've only put maybe 6k miles on my car since changing mine. There have been reports of people shredding bearings after putting some hard miles on with one of these, so just be aware of that. If you search deep enough on this site and a certain tech forum you can find those posts; however, I imagine it's a very small percentage.
There's also ATI's super damper, but I'm not sure if it's an underdrive or not.
HTH
Le Mans Master
Joined: May 2006
Posts: 7,874
Likes: 253
From: Hillsboro OR
I opted for a PowerBond 10% UD pulley when I did my H/C. The only "downside" I can notice is that the voltage (read on the DIC) at idle is now 13.6V, instead of 14.2V. That is only at idle though.
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