When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
Looks more like an overflow than surge. Difference is overflow is just that. Surge is high spot in cooling system and part of the systems' coolant flow path.
Only flow of reflow tank sees is burping of high pressure coolant when things get hot and then as cooling happens vacuum draws fluid back in to radiator.
I'd ask:
1. What is the high point (where air will collect when filling)? If radiator then you just need an overflow. 13 lb cap would be good.
2. If the surge tank will be highpoint you'd use a higher pressure cap on radiator and 13 on surge tank.
3. Another consideration... Where will you attach steam vent? This needs to be within pressurized system. Overflow tank is not pressurized... Just atmospheric
This is very simple and covered here on countless threads. A search on steam vent will have you reading for hours if you choose.
If the radiator tank and pressure relief cap are the high spot, I'd only install an overflow. It is exactly what I did and works great. I used an overflow from a Sububran and bought it new on Amazon for $15.
If there is another high spot in your system, that won't work. I'd then install a surge tank.
As for the inline steam vent, it works great. I built one with 1 1/2" AL tubing and a -6AN male bung that I welded to the tube. See photos. Or you can buy similar from Jagsthatrun.com
I use the vintage air heater controller inline in one of the water heater lines. Pay special attention to the water flow and directions on your heater controller valve. Some of the valves only work in one specific direction.
In that case you would just eliminate the surge tank and use the heater in and heater out ports of the water pump as depicted in the diagram to go directly to and from the heater core.
6 Common C5 Corvette Failures and What's Involved In Repairing Them
Slideshow: From wobbling harmonic balancers to failed EBCMs, these are the issues that define long-term C5 ownership and what repairs typically involve.
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph
Slideshow: A modern Camaro transformed into a retro icon, this limited-run "Bandit" build blends nostalgia with brute force in a way few revivals manage.
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked
Slideshow: Cadillac didn't just crash the high-performance luxury vehicle party, it showed up loud, supercharged, and occasionally a little unhinged...
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes
Slideshow: A one-off sports car that looks like a vintage Italian exotic-but hides a C6 Corvette underneath-just sold for the price of a new mid-engine Corvette.
Please explain cooling system... 
