You may want to redo the timing. I just had the same problem. I have a functional gt350 hood on my 65 and it got water all over everything. We started replacing things one by one dist cap, spark plugs, points, retiming, then an entire distributor and vaccum. It ended up just being that when we timed it my motor acted like the timing was to low so we advanced it and it runs exactly how it used to. All motors are different so timing varies. If not that you may want to check the fuel filter connected to the fuel pump, sometimes water gets trapped in it.