car still vibrates and has hard start

did you do a compression test to verify the motor is good??

Roy

Is this a carb conversion? Are the jets dialed in?

Disconnect the brake booster vacuum hose from the intake and plug the intake
to see if that makes a difference.

Thomas

Yes I did do a compression test. When I replaced the intake manifold gasket I discovered that the exhaust manifold had a crack on it

Now what happens is that my brakes would go to the floor sometimes and I've just replaced cylinders, drums and shoes. I did bleed!