Interesting replies, thanks guys. I'm ordering a Koyo R-core radiator... if this doesn't solve it, I'm not sure what I'll try next!

 

well the thermostat in those cars are very restrictive and can start cavetating i have a 350z and i have tp and a pop charger and mine never get much over 230 be sure you dont have any air bubbles. Let your car idle for a bit and turn your heater on full blast if its hot then you most likely dont have any bubbles but if its just warm or even cold and gets warm when you rev it up you have a bubble. On our APS TT it has a koyo rad and it still over heated with 30% coolant and water wetter we had to remove the thermostat to make the car not over heat. Good luck hope it all works out.

 

I know this thread is old but wanted to add my 2cents. When I was running my OEM radiator and overheating at the time, I tried coolant/distilled + water wetter and my car still overheated I don't think water wetter works very good if you're driving your car hard. After getting a larger radiator and a fan kit no issues also using a 50/50 coolant water mix.

 

100% water + Water Wetter works for me too.

 

Evian and wetter