Underdrive Pulley insight ...
Thread Starter
Cruising
Joined: Apr 2009
Posts: 11
Likes: 0
Underdrive Pulley insight ...
I read about the new pulley (HARMONIC BALANCER / UNDERDRIVE PULLEY for: LS1 / LS6 / LS2 / LS3) and its benefits. Does it really help with performance? Is there a wrong way to install it? How hard is it to add the locking key during installation? Is there anyone out there that might have some important information or insight about this new pulley or the installation involved? I found it in 2 different places, it looks like the cheapest place so far is Corvette Central @ $214.95
Thread Starter
Cruising
Joined: Apr 2009
Posts: 11
Likes: 0
The underdrive pulley's actual description is "HARMONIC BALANCER / UNDERDRIVE PULLEY for: LS1 / LS6 / LS2 / LS3", I plan on putting it on my 02 Z06. Just wondering if anyone has used it and what they thought about it, its pro's and con's...
Burning Brakes
Joined: Aug 2006
Posts: 1,217
Likes: 5
From: Stark County Ohio
Personally, I feel that a smaller diameter outer pulley section that you have with an under-drive pulley provides LESS ability to dampen (absorb) crankshaft vibrations.
Another consideration is the possibility of under powering the generator (alternator) on a street driven vehicle. To a lesser degree the water pump may not work as efficiently under some conditions..
Many run under-drive pulleys with no ill effects. Your choice.
I would advise that you pin the crank using the ATI fixture. This method utilizes the keyway found in most aftermarket balancers.
Pulling the rack is the bitch; the actual pinning process is simple and straightforward.
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Another consideration is the possibility of under powering the generator (alternator) on a street driven vehicle. To a lesser degree the water pump may not work as efficiently under some conditions..
Many run under-drive pulleys with no ill effects. Your choice.
I would advise that you pin the crank using the ATI fixture. This method utilizes the keyway found in most aftermarket balancers.
Pulling the rack is the bitch; the actual pinning process is simple and straightforward.
--
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
I have a POWERBOND 25% underdrive damper and have ZERO negative issues with it. I also have a 240 ish duration cam and it dampen fine and have no charging system voltage issues. My idle is set at 890 RPM. I also used the ATI Pinning kit. FANTASTIC pinning kit! I also used the ARP damper bolt to secure the damper to the crank. If your going to pin the damper to the crank, make sure that you purchase a damper with a key way machined into it. The stock OEM damper DOES NOT have a key way!
Changing the damper is not a difficult job if you have ALL the proper tools and can understand the procedures. Its involved but not impossible!
Changing the damper is not a difficult job if you have ALL the proper tools and can understand the procedures. Its involved but not impossible!
