I think the timing is very close - it was too far advanced last fall so I retarded it a bit this spring. Maybe it needs to go a bit further.
I have not yet adjusted the valves - it seems to me timing gets set before the valves. I'll double check the timing with a vacuum gauge, change the gas, set the valves and report back.
To be clear, this is a Chevy 216 which came stock in Canadian GMCs. Thanks to all.
