Rep Power: 863

Some more love I picked this up from summit racing.

Part Number: FLU-650221
Engine Balance: External
Balance Style: 50 oz. imbalance
Safety Rating: SFI 18.1
Degree Markings: Yes
Degree Marking Range: 50 BTDC to 10 ATDC
Outside Diameter (in): 6.625 in.
Harmonic Balancer Material: Steel
Harmonic Balancer Construction: Fluid
Harmonic Balancer Finish: Black zinc chromate
Mounting Hardware Included: No
Quantity: Sold individually.
Notes: Additional timing/degree marks at 90, 180, and 270 degrees.

 
Rep Power: 753

Check with your engine builder that your bottom end was balanced to 50oz, I'm assuming it's got a stock dampner on the snout.....
SS