replaceing the viscus fan wit electric one

[austin360]

hello all was getting back to my 325 sport was gonna remove the viscus fan and put electric one was wondering how do you wire it up to make it come on when it needs to and what type of fan you would use and would you change the rad to a bigger one any help on this would be great ...oh and im only intrested in taken it off to reduce the lag on the pully as the engines cooling is ok as well

[daimlerman]

Viscous is far more efficient than an electric fan,why change it if it's not broke?

[Rav335uk]

Keep the viscous on, it doesn't draw that much of the engine.
We M30 boys have to have a electric fan, but the amount of times i keep blowing fuses is not funny.
Here's a link anyway.

http://www.aaroncake.net/rx-7/efaninstall.htm

[Brianmoooore]

Any drag removed from the water pump pulley will be replaced by drag on the alternator pulley! Electric motors don't run for free.

[murran]

if the viscous is working its the better than any electric fan. it doesnt really take any power from the engine that youd notice and electric fans still produce drag thru loading up of the alternator when they cut in. for the most part a viscous is unloaded and simply idiling, you could stop it with a newspaper!!
bigger rad? unless your running some sort of huge turbo application, producing much more heat, you dont need it.
if the system is healthy, its more than up to the job of keeping things from overheating.

ive put a cooler thermostat in mine, 80 degrees insted of the 88 standard 325i one and im running an e21 25 year old rad with standard viscous fan. still keeps a 325i engine happy while drifting bouncing off the rev limiter........