Overflow tank recommendations?

[Cannoball888]

I'm looking for an aluminum or stainless steel cylinder overflow tank for my '65. I see that Summit has a slew of them, but I'm not sure which one I should get. Do all of the designs allow coolant to be returned to the radiator when the engine cools? Is there a difference between an overflow tank and a catch can? What is the practical difference between vented and nonvented? What is circulating and noncirculating? Also, what is the minimum size allowed by the NHRA? I appreciate any help with my newb questions.

 

[66HertzClone]

In order for the coolant to be returned to the radiator you will probably need to replace the radiator cap. Check your current rad cap, it needs to have two rubber seals in order for the coolant to return to the radiator. The smaller inner seal rests against the smaller opening in the rad neck, this is the pressure seal, it opens when there is enough pressure to move it off its seat. The coolant then moves thru the hose to the overflow tank. The second rubber gasket seals against the outer ring of the radiator neck.

After the engine is shutoff and the coolant cools, the contraction of the cooling fluid creates a a vacuum in the radiator, this pulls the coolant back into the radiator. This action will not work if the outer seal on the rad cap leaks air, or if the end of the hose in the overflow tank is not submerged in the coolant.

The plastic tanks at summit are just catch tanks, they may not work as a recovery tank since the inlet is at the top of the tank. There is a drain at the bottom of the tank, no tube or way to keep the inlet tube submerged in the coolant. I used a tank and cap from here for my recovery system. http://www.kanterperformance.com/html/overflow_tanks_-_universal.html



When I installed my aluminum radiator I used AN4 braised hose to connect the rad and tank together. The inlet on these tanks is on the bottom, so the suction returns coolant back into the radiator. I even purchased one of the smaller tanks and am using it as a washer fluid tank.

 

[Cannoball888]

Thanks. I just ordered one from kanterperformance, and a cap too. It was a better deal than anything Summit had. Most of Summit's tanks of the same dimensions were more expensive, and they don't even come with mounting hardware.

 

[brianj5600]

I use this one http://www.jegs.com/webapp/wcs/stor...irect&categoryId=21525&parentCategoryId=10127 The natural color is see through enough you can tell how full the system is.