John, peak torque happens at a pretty low RPM, your SBC will be happier at a higher RPM shift point. We shift our Heritage JrFuel about 1,000 RPM higher [ 9800] than what our dyno chart showed peak HP 8800 rpm, [ peak torque is @ 6800 rpm]. Now as far as shifting higher so the engine doesn't drop below peak torque, unless you have some kind of problem and have to shift early [ tire shake ?] your engine will drop after the shift to where your converter flashes at [ true stall]. We can shift at 9200 or 10,300, and it still drops to 8600 rpm. We run allot of 7.0's @ 186-189 mph with a 4.88 gear and 31x12x15 GoodYear.
I wish my dyno guy could run it up higher than 9,000, because of our higher shifts, the hp does drop some from 8800 to 9000, but only 6 hp. Between 8100 and 9000 the hp only gains and loses 6 hp on the dyno chart.
BTW, I always look at the RacePak run for the converter flash rpm, it's a good measurement of increase-decrease hp for my tune-ups. More power = higher rpm flash. Lower flash I went the wrong way.
Kinda think of your converter like a slipper clutch, more power = more slippage.
If you are looking for more power [ Dah, who's not looking for more hp, unless you bracket race] call your cam guy for a better cam for your application, and tell him the rest of your engine combination, so he can advise you the rpm he should grind your cam for.
Cam and converter changes will give you the most increases in performance, unless you have the wrong slicks.
Have fun, I hope this info helps.
Jon
