New underdrive pulley!
Thread Starter
Instructor
Joined: Apr 2009
Posts: 242
Likes: 1
From: Pictou Nova Scotia
New underdrive pulley!
I am going to order a underdrive pulley for my 99 FRC. I understand that the original isn't keyed or pinned. Is it necessary to pin or key the new balancer to the crank? I can assure you there will be not turbo or supercharger in my future. Just basic bolt-ons.
Burning Brakes
Joined: Nov 2006
Posts: 989
Likes: 8
From: Chino Ca.
When I installed my PowerBond pulley I pinned it, for the piece of mind.
I sleep very well at night
Mine was perpendicular.
I have since removed the pulley and re-installed with no problem at all.
I sleep very well at night
Mine was perpendicular.
I have since removed the pulley and re-installed with no problem at all.
Race Director
Joined: Feb 1999
Posts: 19,659
Likes: 34
From: Lenoir City Tennessee
Ci 6, 8 & 10 Veteran
St. Jude Donor '05-'06-'07-'08-'09-'10-'11-'12-'13-'14-'15
Since the balancers are not keyed on, is there a wrong way to install the balancer? 
The reason I ask is I just pressed my underdrive balancer on when I was building the LS motor for my 70 and let it be.
The reason I ask is I just pressed my underdrive balancer on when I was building the LS motor for my 70 and let it be.
Tech Contributor
Joined: Jan 2007
Posts: 19,470
Likes: 1,171
From: Dyer, IN
More important on a C5 (depending if it's an auto or manual), if a stock balancer is used, etc.
Tech Contributor
Joined: Jan 2007
Posts: 19,470
Likes: 1,171
From: Dyer, IN
No biggie. You can always pull it back apart and pin it if it comes loose....right?
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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
The GM procedure for a MANUAL C5 is to mark the OEM damper orientation on the MANUAL Tranny crank and reinstall it in the same position. Remove the OEM damper balancing pins and position them in the NEW OEM damper. 
If you use an AFTERMARKET Damper,,,your on your own. I just installed my Powerbond damper and all was well!
I pinned mine for PIECE OF MIND and have NOT had any issues!
BC
If you use an AFTERMARKET Damper,,,your on your own. I just installed my Powerbond damper and all was well!I pinned mine for PIECE OF MIND and have NOT had any issues!
BC
Safety Car
Joined: Sep 2003
Posts: 3,558
Likes: 2
From: Cape Coral FL
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 if you key it 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
