EDIT: You posted your power/weight while I was typing.

I don't know what power/torque and weight you have, but at over 3200 pounds and 1.2x sixty foot times, I think my combo is getting high (but not awesome...).

5 clutch front drum with Alto Red Eagle clutches
5 plain steels
0.075" clearance
Griner valve body at 165 psi

3.8 lever, dual spring servo (old style), ie trying to avoid 2-3 overlap which can hurt the clutches.

I have hundreds of passes on this clutch pack. I would have to add up several logbooks and see exactly when I put these Red Eagle's in, but it could be 600 passes. The last time I had it out for inspection was 240 passes ago and the frictions and steels were excellant.

1993 Daytona, 5.50 at 130mph (1/8) 1.19 sixty ft (PG). Link to 572 B1 - Part 1