disagree on this one Philbert mate. I have a big rad core as do a couple of my mates who run decent power. They have all still had probs at some point, e.g. I had to slow up at Silverstone Ford Fair.

Temps are controlled much better with the turbo coller fitted as the superheated water normally just goes straight back into the tank then round again into the main system.

This way it goes back in with a good deal of heat knocked out of it. tbh I was suprised how well these worked in their cars and plan a custom one for my 500.