Need some advice on timing
 

I have a 1969 2.0L. Started life as an E, now has Webers on it. I'm having trouble determining what I should set the timing to. The distributor is a Bosch mechanical advance only. Should I be setting the timing dynamically and to what settings. Should I be making allowances for an E block with normal carburation. Would I be better off upgrading the distributor and to what.
Thanks

around 35° total seems to work ok for good bottom end power. the old hot rodder's method of advancing the timing until it causes pinging and then backing it off until it doesn't, seems to end up at around 35° total advance on most cars. kind of like guitar strings, low as possible without buzzing.