How to install the balancer hub?

[TraceZ]

I'm looking at a balancer hub for a LT1 and dont understand how to install it in the proper position.

I used the search feature and found instructions to put the #1 cylinder at TDC and the install the hub with the arrow at 12:00.

The problem is that I dont see an arrow on it. What gives? It has a hole in it on one side, but no arrow.

[Rob B (shoebox)]

On the hub, there is no arrow, but you should see a line cast into it that is for the same purpose.

[TraceZ]

Ok, I've got the hub in my hand right now, but dont see anything I would call a definite line cast into it.
It has 3 fingers protruding from it, each with a bolt hole in it. There is a different casting irregularity between each of them. Here are pictures.

[Rob B (shoebox)]

Yours is a little different than mine, but the top pic, with that little hump looks like what I am talking about. Look inside the hub and see if the shadow line of where the crank key would be, matches up to that hump in the 12 o'clock position (crank at #1 TDC).

The hub spokes are not symmetrical and I am pretty sure that the ones where the distance is widest between them is where the mark should be for indexing it straight up.

[TraceZ]

Ok, I used a marker and extended the mark from the keyway around the outside of the snout. This is how it sits in the cam gear. It ended up that one of the casting marks lines up perfectly with the dot on the gear. I drew a black line on the mark to highlight it. It looks right to me!

[Rob B (shoebox)]

That's looking right to me.

[fastTa]

Tracy, Thunder Racing makes a crankshaft hub with a keyway. I would highly reccomend using one of those since the stock LT1 crank already has a keyway itself. Reinstalling a hub with just an impact wrench wil usually be OK, but why not do it right and not trust a simple press-on fit for reliability. There is a short and long version of the crank hub. You will need the long one.

Another thing is that on an LT1, there is no harmonic balancer, just a crankshaft dampner. So the position of the cranshaft hub is important due to the casting chracteristics, but the relative position of the actual dampner pulley is irrelevant.

Keyed is the way to go.

http://www.thunderracing.com/catalog...vid=4&pcid=239

[TraceZ]

Thanks for the pointer Kevin. i'll make sure I get one of those. Sucks I spent time cleaning this one up.