The hose at the back of the engine more then likely could have been rubbing, I split a hose twice until I hit the shit out of the firewall!
I had loads of issues with cooling, whilst drifting mind, but slower traffic was a issue. I ran my fan on below 45mph, but normal driving its fine and sits just over half and a constant.
How much of the standard bodywork do you have infront? Its not a pretty picture as I was halfway through the work but this is what i did to mine, all the front apron I cut away so the whole radiator was exposed
I then put 10 holes in thermostat and havent had an issue since with the cooling, only whilst drifting or stationary traffic it creeps a little. But hard/track driving its fine.
Im going to step up to one of these soon as it fits on the existing mounts
http://www.mishimoto.co.uk/mishimoto-bm ... 99-02.html