Ok, so the car does not have a heat riser on the exhaust manifold.

I have some baffling between the top of the shroud and the radiator support. There is nothing on the sides but a 1/2" gap that could be filled I suppose.

The pressure buildup is from steam not exhaust gasses as this hose blowing event only takes place with the engine off.

The new water pump does not have a cast impeller, and as far as the distance between the plate, it is what it is, not sure how to get it closer.

The car has always run hot,I have just put up with it, but I am on quest to resolve this problem once and for all.

I thought the new plate would solve the problem.

I am leaning toward the 4 row upgrade.

$400

Trying to avoid spending this but it might be money well spent.