RS2 Cooling System

[Rusty]

I've noticed that over and above the different water pump pulley, there are other differences between ABY and ADU cooling systems. These include a different routing for the header tank hose, which goes to the turbo water feed (why is this) and also a restrictor that sits near the thermostat, whose function seems to be a matter of debate. Anything else?

http://www.s2forum.com/forum/showthread.php?t=3612

[Rusty]

Is it worth the extra £60 to go to RS2 rather than stick ABY?

[Veg]

The header tank pipe feeds to the engine side of the thermostat rather than into the bottom of the radiator. I suspect it is to condense any potential steam before it gets to the thermostat operating like a swirl tank. I suspect the cooling system operates a little harder in an RS2 hence the pump spinning faster and cavitation might occur hence the need for some form of condensing

[UrS4boy]

The header tank pipe feeds to the engine side of the thermostat rather than into the bottom of the radiator. I suspect it is to condense any potential steam before it gets to the thermostat operating like a swirl tank. I suspect the cooling system operates a little harder in an RS2 hence the pump spinning faster and cavitation might occur hence the need for some form of condensing

Umm...good try. I can imagine the possibility of cavitation but the possibility of steam needing condensing, I can't buy. The system is under sufficient pressure that the coolant can't boil, i.e. change from a liquid to vapours. That and the thermostat is 87C, well shy of the 100 C needed at atmospheric pressure and way less than the 121C needed to boil at 2 bar (1 bar relative).

http://www.engineeringtoolbox.com/boiling-point-water-d_926.html

[rj scotty]

Our cars are not prone to over heating in my experience, i doubt the rs2 system is worth the extra money in the real world

[macspring]

Our cars are not prone to over heating in my experience, i doubt the rs2 system is worth the extra money in the real world

I would tend to agree, my fried S2 avant driven in summer city traffic never went outside the normal operating temperature range even without it's auxiliary radiator.

The only difference being the second speed of the radiator fan cut in a lot more than previously when the auxiliary rad was fitted.

If I was unsure of my cooling system, I'd flush it in all of the different sections with a hose, whilst the thermostat is removed from the system and then replace the thermostat with a new Beur 87 degree one, testing it in the kitchen before fitting it with a new rubber seal.

[mcandmar]

I can see the advantage of the pump setup as it will increase coolant flow through the head where it matters, but unless your doing high speed autobahn runs or track days i wouldn't bother with it. The different header tank plumbing, and from memory something was also different with the after run pump setup was always a mystery to me. One does have to question their expertise in such matters as Porsches were still air cooled in the mid 90's

[s2driveruk]

Flush the system and for £160get a new behr radiator and I reckon you will be just fine. Having recently changed mine, it does seem like temperature control is better and the fan isn't kicking in as much, probably less scale etc to reduce efficiency. Also use a decent, premix coolant so there is no use of tap water and it won't scale up as quick either

[Veg]

In the real world I doubt there is much in it but those fellas at Porsche must have had a reason

[macspring]

One does have to question their expertise in such matters as Porsches were still air cooled in the mid 90's

Well observed.

[Rusty]

Car has no overheating issues but if there's room for improvement and I'm replacing the lot anyway, then it's £60 exta 15-20%. I'll look at getting a large core radiator although my rad was replaced less than 10k milesvago. Good idea about filling with deionised water; other option is waterless coolant.

[Error404]

One does have to question their expertise in such matters as Porsches were still air cooled in the mid 90's