suggestions on timing on 70 340, programmable ignition

So how much boost is it capable of generating? The engine is really closer to 9.5:1 with those pistons and open chambers. So you should be ok. The cam is not what I'd use for a supercharged application. WAAAYYY too much overlap. That being said, I'd say sart with an initial timing figure of 10°, bring it up about 10°/thousand rpm beginning at 1000, with a max total of 32. Start from there and see what it likes.