Wrong size harmonic balancer?

[C101971]

So I think I made a fool of myself but I'm here hoping to understand fool myself. I bought a new harmonic balancer for my 71 c10 350 motor cause the old one was wobbling pretty bad. I failed to read the whole description and found out I bought a gen 1 350 harmonic balancer so it's smaller than my factory one. In theory no big deal, everything is timed and running good but if ever or when I need to change something timing related I'm kinda hooped.

So I was more curious if anyone knows if there are timing marks out there to accommodate for people like me who have made this mistake? I know I could just buy the correct one but a timing mark is cheaper than a balancer. Been looking around with no luck and I figured there has to be one, the marks would be in the exact same spot, just closer to the balancer. Right now I have an inch of space, maybe more, from the balancer to the marks.

It can be done changing the timing but it won't be accurate.

[jocko]

I think you mean you bought a Gen II motor (i.e. 1992+ LT based) damper for your Gen I 350, yes? Believe some Gen II dampers were 6.75" and original truck 350 dampers were 8". Or it may just be that some vehicles got the smaller damper, regardless of Gen. But trucks generally had the 8" I believe. Not aware of anyone that makes a compensating timing mark for this. Understand the concern about timing accuracy, but your old pointer is 9/16 further away from your timing marks than you old damper setup - so I don't think you'd be "that" far off setting your timing as long as you are sighting your timing light and eye line of sight directly at the extended crank centerline. The dampers "should" be interchangeable otherwise as both are internally balanced engines.

Having said all that, it would drive me nuts and I'd return it for an exchange of the correct diameter one or a refund.

Also consider the fact that not all dampers across all years were marked at 0 deg in the same place relative to the crank keyway - another reason to get the correct one for the year motor/vehicle combo. But if you have the old damper, you can at least compare to see if the zero mark on the damper is in the same relation to the crank keyway.

[C101971]

Originally Posted by jocko

I think you mean you bought a Gen II motor (i.e. 1992+ LT based) damper for your Gen I 350, yes? Believe some Gen II dampers were 6.75" and original truck 350 dampers were 8". Or it may just be that some vehicles got the smaller damper, regardless of Gen. But trucks generally had the 8" I believe. Not aware of anyone that makes a compensating timing mark for this. Understand the concern about timing accuracy, but your old pointer is 9/16 further away from your timing marks than you old damper setup - so I don't think you'd be "that" far off setting your timing as long as you are sighting your timing light and eye line of sight directly at the extended crank centerline. The dampers "should" be interchangeable otherwise as both are internally balanced engines.

Having said all that, it would drive me nuts and I'd return it for an exchange of the correct diameter one or a refund.

Also consider the fact that not all dampers across all years were marked at 0 deg in the same place relative to the crank keyway - another reason to get the correct one for the year motor/vehicle combo. But if you have the old damper, you can at least compare to see if the zero mark on the damper is in the same relation to the crank keyway.

Everything is Mark to mark on both balancers, yes I meant gen 2 balancer on a gen 1 motor. Re looked at the packing slip and it did say a gen 1 balancer so maybe they sent the wrong one

[jocko]

I think there may have also been some smaller dia Gen I balancers, but not stock on our trucks. If they knew your application was for a 71 350 truck, then they sent the wrong one.

[Bigdav160]

No way to get a LT balancer mixed up with other SBC's. It's a separate hub with bolt on balancer made for a belt.

Vortec balancer? That might be a DIY project with balancer tape and a piston stop.

[roboticjunky]

Camaros, Firebirds, and Corvettes had a smaller harmonic balancer. Probably because they revved higher than the truck motors. I had a 87 Trans Am and the balancer was smaller than my 87 V10 (aka K10). Both had stock 350 engines.

[72LB]

As stated Gen 1 engines had two balancers 8" and 6 3/4". If you have a 6 3/4" you will need a timing tab for it, bolts to the timing cover.

[C101971]

Originally Posted by 72LB

As stated Gen 1 engines had two balancers 8" and 6 3/4". If you have a 6 3/4" you will need a timing tab for it, bolts to the timing cover.

Yeah that's what I think happened, they just sent the wrong one. A timing tab off a 350 with the smaller balancer should just bolt up to mine though right? I don't see why it wouldn't

[Rickysnickers]

Yes, it should.