Recently bought this ATI balancer as it is listed for all big blocks.

Putting this on the hemi in the road runner, which till now had a balancer that aligned with the 383-440 pulley set. I do have a double groove pulley on my alternator, and the belt went around the inner groove.

Now that it is on, it definitely needs the 69-71 hemi water pump pulley, as it aligns perfectly with the outer groove on my alternator pulley, which is the double groove pulley.

It is a thicker dampener, not as thick as a stock 69-71 hemi, so I didn't really think about it when I put it on.

There is also only one other ATI at Summit that was available, and it didn't list the thickness, so I just went with this one.

Anyone know what's up here? Or have an ATI part number of a dampener you have used?

Thanks!