I designed a surge tank last week and had my local machine shop fab it up for me. It consists of a billet upper neck with a 1/8″ NPT port for a -4 overflow line. On the upper front a -8 weld-on XRP double o-ring port that leads to the top side of the radiator. A weld-on -4 AN nipple at the top side for the steam ports. Then at the bottom left two -8 weld-on XRP double o-ring ports for a pass-thru from the heater core to the front inlet port on the water pump:
All of the lines mocked up:
I got off my ass and finished the heater core setup the other night. I cut the hard tubes down as far as I could and still allow me to get some 5/8″ heater hose onto them securely.
As you can see I basically cut them down to the rib on the tube:
I then simply sanded down the tubes so they were basically smooth:
This is how they mate up to the backside of the machined bulkheads in the car:
Some simple heater hose and temporary hose clamps… it’s done. I will ditch those nasty hose clamps for the final install and use some XRP Ensure Clamps.
I also mocked up the radiator hoses:
I will be doing a surge tank for my high point in the coolant system. I will be running the steam ports into the top side of the tank, looping the output heater hose through the bottom of the tank and then into the front port on the water pump. Since I have never done a surge tank before, I do have one question if anyone can confirm it: do I absolutely need to run a port from the top side of the surge tank to the top of the radiator?
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