in arizona with our high temperatures, the 98,99 2000 model year e46's came with both belt driven fan on the engine and electric auxillary fan in front of the radiator for an assist or for the a/c, this is the way most of the automatic trans cars came, the manual transmission cars in some cases came with the electric fan replacing the belt driven fan. I seem to see almost every late model manual e46 this way. These seem to blow headgaskets and crack blocks here at a much higher rate than do the automatics with the belt and electric fans.
I suspect that when the fan fails and the car starts to overheat in traffic it happens much much quicker with the electric only fan cars, the belt driven fans seem to heat up slower since with a bad fan clutch it still moves some air and this gives the owner more of a warning time before the car cooks itself.
To me the slight gain in performance not having a clutch fan is not worth the potential risk when a electric fan fails. Also the aftermarket fans seem to fail at a much higher rate than do the factory fans.





Quote Originally Posted by nosdbmr
I am using a Greddy 14" Fan and as to installation it is very easy, it just depends on how you want to install it (switch turn on or sensor turn on). And as to the bore yes we be bored it .20 over so in mm I am not sure what that works out to but probably very similar. I deal with inches so??? For pistons I believe it or not had a custom made set of Wiseco Pistons made as they had never done any for the application that I was looking for. Same gasket for the head but like I said we decked the head, the only down fault with my motor is I cannot run more nitrous due to no one makes a chip that will allow us to retard the timing everyone wants to advance it with there chips. So I then had to put in an SAFC which allows me to do this. So if you are going to run Nitrous and the motor is built for it, spray away and you will love what the response is.