electric fan temp switch/sensor

[Nacho-RT74]

whats the best place and which one ? A friend of mine wants to mount an electric fan with double speed. I know the water pump housing provides places where we would be able to mount the switch/sensor, but is that the best place or better try to modify the rad to mount it ?

Beside that, only switches/sensor we have found are really low rated for high speed to what I think is normal on a muscle car ( around 85º Celcious ) and even lower if we think Mopar engines work hot. Working temp is normally noticeable ABOVE that and would make keep working the fan allways on high speed... which one would be the best to the car ?

400 4 bbls.

[Plumcrazy]

I would try to get it as close to the outlet side of the thermostat as possible.  That's where the water will be the hottest.

[Nacho-RT74]

Yeah I thought that. Hosing provides two more outlets at a side of heater outlets.

but wich one ? we are only able to find 4 cilinders Fiats switches by the moments, and all are 4 cilinders with low rate temp. Taht would make ALWAYS work at high speed

[Steve P.]

Natcho, I don't quit understand. You only need the fan on when sitting in traffic or when the T-Stat opens. Why do you need off plus 2 speeds?  On and off is fine..

Also I would mount the switch in the radiator as the fan only needs to be on when the fluid in the radiator is above your set temperature. You will read more heat longer at the T-Stat housing than at the rad. especially when driving highway speeds...

[Nacho-RT74]

my buddy doesn't use T-stat... they were removed on all cars here and PROBABLY never were mounted from fac, living in a tropical country. I "re"installed on mine thought

well is not really my bussines, is a guy here ( chebby guy ) who is selling the double speed fan to my buddy with a 73 Charger. We are thinking on several options. If was me I would install also a double switch and fan speed and if was posible would it be low speed at 80º Celsious or so and high speed at 110º Celsious or so.

BTW he will eliminate the fan clutch and fan itself, just will keep the pump working with belt, sorry I think forgott to mention that. that's the reason why the double speed.

[Steve P.]

I guess that is a way to do it. I would just run a 160* Stat and the clutch fan. The clutch only really steals power when the radiator is hot and releases when it's not. Some electric fans will pull so many amps that the alternator is running hard all the time eating more power and mileage.. Also the wiring on our old cars is not designed for the extra pull of amps. Why stress something for literally no gain?? I could understand if it were 500 + HP sitting in traffic for a long time or an add on fan on a tow vehicle..

For me it would be a t-stat and clutch fan.. Just my .02

[Nacho-RT74]

I preffer also the original fan with clutch and T stat, but is what he wants ( the chebby guy fill his head with stuff ) and I'm just trying to help on what he wants.

anyway, the wiring won't be a problem, I'm dealing with that on his car and making the rebuilt job and upgrades . he already have a newer alt.