davidfromphoenix
New member
I too am APR K04 and track very hard on road courses. If its warmer than 70*F outside, temps will get to 240+ very quickly, usually meaning I have to back off, and hopes for good times that day go down.
I have heard of others running a 70/30 mix of dist. water and coolant, but the owners manual states you should not run less than 60/40 dist. water and coolant. I was going to do a full coolant flush (to remove the possibility theres air in the thermostat as the radiator has been removed a few times now) and swap to that, as well as add water wetter.
Will report with findings
I have the exact same setup with the exact same problem - my Mk6 GTI w/K04 gets to 240+ very quickly on track, even on very cool mornings (albeit, I live in AZ). I've got an an auxiliary oil cooler installed inside the engine bay with its own fan, which makes almost no difference for coolant temps on track - go figure. Wish our US GTIs came with oil temp sensors, so I knew if it was helping.... anyway, from some consulting with a few "experts", including Ron Davis, who happens to be a friend of mine, I've got three routes I'm considering at this point to solve this:
1) upgraded main radiator **
2) finding a way to install auxiliary rads (like on the Golf R)
3) divorcing the coolant system from the oil system somehow, to stop the oil temps from affecting the coolant. Tryolsport recommended this when I talked with them, but didn't have a solution available anymore.
** My other issue is my GTI happens to be a CBFA engine, so upgrading the radiator guarantees a CEL, and nobody I've talked to believes they can work around it, besides Ron Davis, who is the most expensive.
Ron Davis also recommended ensuring I was getting optimal airflow to the radiator, including possibly damming air up into the rad, and to look for possible areas of low pressure to create vents to increase airflow. I don't know how feasible the former would be on a Mk6 though.
Anyway, just wondered if you'd had any luck since you last posted, including your change in mixture, water wetter ,etc... Also, if anyone with a Mk6 is interested in going in with me to have Ron Davis make a few world-class aftermarket rads for us at a reduced cost, I'd definitely consider that heavily...