Is that the old R286 roller (286@.050, .750 lift)? I seem to remember the seat-to-seat was 332 or close to it...

The DC catalog had a pic of the cheater cam (.473 lift but 352/380 seat duration) and those lobes looked just about square.

One of the car mags had one lying around and tried it in a 340 or a 360... wouldn't idle below 1800.