I'm running 10.7:1 on my 383, and set the timing to 10-12 degrees initial and 36 degrees toal by 2800. You should run at least 93, and set your timing to keep from detonation.
MSD also makes a timing control for under $100, that way you can adjust your timing up to 15 degrees inside your car. Plugs into your distibutor.
That way, when you are ready to play, add good gas and set up the timing a few degrees. When you go back to street, back it down. Cost is high at first, the inital $100, but can save you motor parts later.
I plan on ordering one.
hope this helps.
383 Speed-O-Motive stroker kit with Speed Demon 750, RPM intake,Proform HEI dist.MSD6a box,World Products Sportsman II heads, ported and polished with 2.02/1.60 valves,64cc,TRW forged pistons with 10.7:1 compression, Comp Xtreme 284 cam,Crane pushrods, Comp Cam 1.6 full roller rockers,ATI damper, 40 series Flowmasters, 4.11 gears with TH350 and 3000 stall.Powertrax NoSlip Locker