I am getting my new shortblock ready for heads and intake and cam and after doing some invetory I have 2 balancers sitting there and they are different sizes. The one is 6.25" and I beleive it is original to the 327 in my 68 camaro, I have the original engine still in the car. The other balancer which is 8" came with my new shortblock which is out of a 70 truck or something. I want to use the short water pump so which size balancer should I use? I eventually will buy an aftermarket one but for now which one? And also what motors used the 8" balancer and which ones used the 6.25" balancer?

Thanks, Erik

You know, I was wondering the same thing for my 67 327. Not sure if an 8" balancer can be used with my current pulleys (PS, Crank, etc) as I think that there will be clearance issues and not sure if the smaller balancer will do the job.

Erik,
I believe the the 327 came with a 6.25 and truck prepped 350's came with a 8" to help with the torque when hauling.

Paul,
I'm using an 8" on my mouse, no adverse effects with reguards to pulleys. Just have to make sure that the timing cover is made for an 8" for the correct year motor.

So the balancers are interchangable. just get the 8" for a 350 of the same year as your 327 with the appropriate timing cover.

I had to do a little bit of cutting on the PS pulley to make it clear the larger balancer when I switched. You can see pics here... (lower pic)

http://www.geocities.com/boodlefoof/page16.html

That's kind of how I had it figured....I wonder if the Z28 PS bracket would clear the 8" balancer???

8" = better and more stable at higher rpms. Great street or endurance damper.

6.25" = light weight and compact. Great on drag race type, short burst applications.

My vote is for the 8", unless it will be drag raced. Stay away from Fluid types if you can......I myself would consider an ATI unit.

I use an 8" steel balancer on my 383, I also have a short water pump. There are no problems with the pulley system as a result of the large balancer.

Just make sure that which ever balancer you decide to use has a timing mark that works with your timing chain cover. There have been a couple different timing tab locations over the years and the balancers were marked to match.

Was the short block balanced using either one? If so, use that one.

I know that they are supposed to be neutral balanced and theoretically swaping should not make a difference, but why chance it if one was used in balancing the engine. JMHO.

No, it shouldn't have been! The balancer or f/w/f/p should NOT be specifically balanced to a rotating assembly b/c then they are dedicated to only it AND can't be swapped to other units like regular balanced stock pieces can..

pdq67

What's wrong with fluid dampners? I thought that they work better for a wider range of harmonics (not that I know anything though).

Sorry, what I meant is that the assymbly was specifically balanced to/with the balancer. The machine shop (should) always requires the flex plate and balancer when they balance the rotating assembly. If one of the 2 he has was used when balancing the engine, he probably should stick with that one (although it probably won't make much difference if they are swapped).

Paul, The Fluid type balancers, although you have pointed out 'FluidDamper' has had problems with certain steel crankshafts. More specifically but not limited to, cast steel crankshafts.

The problems are from a specific harmonic which naturally occurs in both the crank and the balancer seperately. The end result is, a broken crank snout......and from there......who knows.

Wow Tom, thanks for the info. I just thought that the fluid type balancers were a neat product. I didn't realize that they could cause problems.

I still haven't bought a balancer for the 67 327/275....I guess I'll look into an 8" ATI unit.

Honestly, since my 67 will be all stock I guess I could just go with the stock type small balancer....I'm still undecided....