Harmonic Balancer Decision
Thread Starter
Burning Brakes
Joined: Feb 2004
Posts: 924
Likes: 2
From: Kearneysville West Virginia
Harmonic Balancer Decision
I have a 70 350/350 I am rebuilding. The original harmonic balancer is toast, as the rubber is shot. I can have the original balancer rebuilt for $122. It is 8" in diameter and 1 7/8" wide.
I bought a replacement balancer from Advance Auto for much, much less, but it is only 1 3/8" wide, and the rubbber does not seem to be as thick. It is a Proform 66511. My concern is, will this replacement balancer function as original and protect my engine?
I bought a replacement balancer from Advance Auto for much, much less, but it is only 1 3/8" wide, and the rubbber does not seem to be as thick. It is a Proform 66511. My concern is, will this replacement balancer function as original and protect my engine?
Drifting
Joined: Dec 2005
Posts: 1,360
Likes: 3
From: NORTHEAST
I have a 70 350/350 I am rebuilding. The original harmonic balancer is toast, as the rubber is shot. I can have the original balancer rebuilt for $122. It is 8" in diameter and 1 7/8" wide.
I bought a replacement balancer from Advance Auto for much, much less, but it is only 1 3/8" wide, and the rubbber does not seem to be as thick. It is a Proform 66511. My concern is, will this replacement balancer function as original and protect my engine?
I bought a replacement balancer from Advance Auto for much, much less, but it is only 1 3/8" wide, and the rubbber does not seem to be as thick. It is a Proform 66511. My concern is, will this replacement balancer function as original and protect my engine?
I use the GM 6-7/8 balancers on my performance engines for years with no problems,
Le Mans Master
Joined: Jun 2004
Posts: 6,231
Likes: 65
From: Seattle WA
St. Jude Donor '14
I'd just buy a new basic dampner; they're relatively inexpensive and fine unless you need SFI certification. You'll likely get a lot of valid debate on the size of the balancer, but an 8" is fine. The smaller, lighter dampner like the one you bought reduces rotating mass...but it doesn't have the same dampening capacity as the old iron duke. You noted you were rebuilding the engine - is it being balanced?
The "economy" line of dampners are from Pioneer or Dorman; this is typically what you'll get at your local parts store. The only problem I've ever seen with one was a too-tight fit on the crank snout on one of the Pioneer balancers - we got creative with a rod hone and opened it up a touch and it was fine. I've got many of these out there with many thousands of street miles with no issues.
http://www.summitracing.com/parts/PIO-872003/
http://www.summitracing.com/parts/RNB-594-121/
You can certainly spend more - your call
The "economy" line of dampners are from Pioneer or Dorman; this is typically what you'll get at your local parts store. The only problem I've ever seen with one was a too-tight fit on the crank snout on one of the Pioneer balancers - we got creative with a rod hone and opened it up a touch and it was fine. I've got many of these out there with many thousands of street miles with no issues.
http://www.summitracing.com/parts/PIO-872003/
http://www.summitracing.com/parts/RNB-594-121/
You can certainly spend more - your call
Last edited by billla; Jan 13, 2012 at 12:45 PM.
Drifting
Joined: Dec 2005
Posts: 1,360
Likes: 3
From: NORTHEAST
I won't use them on my engines but I know of some shops that have had issues just do a google search on those balancers.
I build some high end engines and prefer the ATI balancers on most of my builds and I have the measuring and honing equipment to fit balancers with don't have to farm that stuff out LOL.
You might check with NAPA as I have seen their balancers and they look like the same company that makes them for GM, And they are priced right as well.
I build some high end engines and prefer the ATI balancers on most of my builds and I have the measuring and honing equipment to fit balancers with don't have to farm that stuff out LOL.
You might check with NAPA as I have seen their balancers and they look like the same company that makes them for GM, And they are priced right as well.
Drifting
Joined: Jul 2006
Posts: 1,259
Likes: 154
From: Deplorableville Nebraska
I have the same engine as you. Had to replace the balancer 4 years ago, and after lots of searches and opinions, settled on a pioneer part #DA-3502 standard, not HD. Also not made in China.......
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Drifting
Joined: Jul 2006
Posts: 1,259
Likes: 154
From: Deplorableville Nebraska
Le Mans Master
Joined: Jun 2004
Posts: 6,231
Likes: 65
From: Seattle WA
St. Jude Donor '14
When in doubt, take a weekend project and replace it...good time for a cam swap
Drifting
Joined: Feb 2005
Posts: 1,879
Likes: 38
From: Los Gatos CA
I am a stickler for originality. I had mine rebuilt by Dampner Doc. They also degreed the dampner. I think I paid $90, but that was maybe 10 years ago. Just another option...
http://www.damperdoctor.com/
http://www.damperdoctor.com/
Thread Starter
Burning Brakes
Joined: Feb 2004
Posts: 924
Likes: 2
From: Kearneysville West Virginia
Thread Starter
Burning Brakes
Joined: Feb 2004
Posts: 924
Likes: 2
From: Kearneysville West Virginia
I am a stickler for originality. I had mine rebuilt by Dampner Doc. They also degreed the dampner. I think I paid $90, but that was maybe 10 years ago. Just another option...
http://www.damperdoctor.com/
http://www.damperdoctor.com/
Thread Starter
Burning Brakes
Joined: Feb 2004
Posts: 924
Likes: 2
From: Kearneysville West Virginia
Drifting
Joined: Jun 2010
Posts: 1,781
Likes: 15
From: Oxford Ohio
I would not trust those chinese balancers if you like your engine.
I use the GM 6-7/8 balancers on my performance engines for years with no problems,
Same here. I just don't trust the metal quality with the Chinese stuff. Realy don't like the machining of their parts.
I use the GM 6-7/8 balancers on my performance engines for years with no problems,
Same here. I just don't trust the metal quality with the Chinese stuff. Realy don't like the machining of their parts.