I replaced the stock airbox on my GST with a k&n and I've noticed that since then the car seems to run a little hotter and cause the fan to kick on more. Today on my way to work I parked and noticed the temperature going up past where it usually does (usually the needle is just below the halfway mark, on this occassion it was about 3/4), so I turned on the heater and popped the hood so that it could get some cooler air than the stuff being heated up by the exhaust manifold and turbo (I dont have a heat shield).

The car only overheated on me once before after some hard driving on a really hot day. Is this kinda normal and a reason to get an aftermarket fan or should I start trying to troubleshoot ?

If the latter, is the first step just getting a new radiator cap ?

Thanks for your help everyone !

do the little/inexpensive things first, like the rad cap and/or flush and take it from there

The stock coolant gauge is crap at knowing what's really going on. Also guessing your car is running hot based on the fans isn't a science either. The only real way to know what's going on is getting an aftermarket gauge or engine management and logging your temps.

It has been hot!... like already said get a new cap and flush out the fluid and run 30% coolant 70% water

It has been warmer the last couple days. Another thing, if you were actually over heating your fans wouldn't cycle, they would just stay on.

Most aftermarket electric fans do not work as well as the stock unit, btw.

Thanks for the advice, everyone ! I'll pick up a new radiator cap and flush the coolant this weekend and maybe even drop some of that water wetter stuff in as well.

I'd put heat shields on but the upper won't fit since I have an aftermarket exhaust manifold. I might get at least a lower at some point though.

put the stock mani back on, and put a shield on it. Or rig some sort of wrap or shield.