I thought I would post this in the event it can help someone else with the same problem. Before modifying my car years ago I replaced all the stock brake components. The car then received a 400 sbc which only produces 10-11 inches of vacuum at idle. The brakes were horrible so I added a Summit Racing vacuum can a few years ago which helped a bit. The pedal was still hard and the car was difficult to slow down so this year I decided to add an electric vacuum pump, a CVR VP655. While not inexpensive I am happy with the results.
I ended up using a piece of steel cut to the size I wanted and mounted the pump to it, then secured it to the inner fender beside the charcoal can. The brakes are much better now and the car will actually lock the front wheels. It seems like a better baseline for future upgrades. The pump can only be heard when you key the ignition but not with the engine running. I think the brakes are getting better as I drive, I don’t think there was enough pressure before to even bed them in properly.
I ended up using a piece of steel cut to the size I wanted and mounted the pump to it, then secured it to the inner fender beside the charcoal can. The brakes are much better now and the car will actually lock the front wheels. It seems like a better baseline for future upgrades. The pump can only be heard when you key the ignition but not with the engine running. I think the brakes are getting better as I drive, I don’t think there was enough pressure before to even bed them in properly.