Correct temperature range

[socalife]

I just swapped a m50b25tu into my e30 and i was wondering where the temperature needle should sit because i have a electric fan hooked up to a misc. button and i usually keep it on which leads the needle to be around the first white mark after the blue. Is that ok or does it have to be in the middle

[tytypetersen]

Depends on which thermostat you used. If you have a 80 degree thermostat, like what the m20 ran stock, then the needle should be in the middle. But if you used the m50 stock thermostat, which I think is 88 or 90, then the needle will be around the 3/4 mark.

And when wiring a fan through the radiator temp switch the fan should come on a hair after the halfway mark. Are you able to turn the fan on/off manually? Because I would wait for the temp to get to the halfway point at least. Because halfway is already colder than what a stock m50 would run anyway(if your running 80 degree thermostat).

[socalife]

I dont know the car was previously a 316i, with a m40 and on my build list i didnt read thermostat anywhere. Anyways what are the effects of running a cold engine

[efficient]

Running rich all the time ^

[Cephas]

I dont know the car was previously a 316i, with a m40 and on my build list i didnt read thermostat anywhere. Anyways what are the effects of running a cold engine

I dont know for sure on an m50 but for an m20 you would be operating in "closed loop" mode from the ecu.

[M3PO]

That's too cold. It should be near the middle.