Get a timing light. Be careful and pay attention to your base timing. I broke the nose off the starter on my 70 with too much base timing (advance seized up at full timing. Next time I tried to start it it kicked back).
Not saying ignition is why its stalling, but you may have another problem with your timing now not helping things.
With 190 psi and a stock cam, you may want to try better fuel than 100LL as you start addind timing.