Forum for competition engine enthusiasts. RIP Guy Croft 09/11/2020 - This forum will continue both as a source of information and as a memorial to Guy.
Below is a picture of the header tank that I have for the water system of my charge cooler.
All weekend I've been trying to lay out the system in suitable positions around the car, and it seemed that the easiest place to fit the header tank was in the front of the car where the spare wheel used to live.
It dawned on me today that the over flow pipe on this header tank needs to be the highest point in the water system. Am I right in thinking that if its lower than any point, gravity will fill it and overflow the tank, and cause air pockets in the system?
I dunno why your tank has an overflow, it doesn't need one - the system won't get hot enough for the water to expand or boil and give any problems, it just needs a sealed system. Blank it off and yes, it will overflow unless it is at the highest point! I would expect it may leak regardless anyway as it has no valve visible on it.
True that it would be nice to have it at the high point in the system, but as you say, not always possible, just add some bleed screws at any high points.
I'm going to rethink my layout to get this at a high point so it gives some ease when filling the system, and will also blank off that overflow pipe as suggested.
The tank must be the highest part of the system. If not, there is no point having it.
The small port on the top is not an overflow, its part of the system, usually used as a self bleed port. You would use a pressurised cap on this tank. The cap will let coolant overflow if needed.
I dont believe you need this tank. Its overly complex.
Thinking about it, I guess I could bleed the system just from the bleed pipe on the radiator by raising a bleed tube from it., much the same as when bleeding the stock coolant system.
I think I'll now look to installing the system without it if thats the case.
The more water you have in your system, the greater cooling capacity it will have.
It is difficult to design a system that meets your needs as your needs are so diverse! For circuit work where you are constantly on boost you need a big rad and plenty of water, for drag/hillclimb use you can get away with loads of water and no rad, water takes on heat many many times more effectively than air, but getting it to give up its heat is the difficult bit.
Really all you can do is to set up the system the best you can and do some testing with temp probes, both before and after the CC unit in the air and in the cooling water then adapt the system accordingly, if your set-up is a one off this is all you can do, there is no way to accurately predict what is needed or what will happen in the many different situations you will come across.
yes you're absolutely right. I was thinking this morning about where to get temp probes and gauges from to run some tests once its running this system. I think I need to concentrate on getting the system set up so it works. Must make that the priority. With a bit of luck it will work well enough to enable Phill Lanes to do the set up and tuning. Then if needs be I can make adjustments to the system.
An area where chargecoolers excel in is on the rolling road, simply connect the CC pipes to the tap and run cold water through it, instantly cures any hot intake charge temp problems distorting the setting up and results!
