Flex-A-Lite Monster Electric

[NVR FNSH]

I have run fanless on my '79 CJ-7 (304 V8), '78 GMC 2wd 1/2 ton 350/350 and '85 Toyota 4wd P/U (22RE 4cyl & 5spd) and not been able to document any MPG improvements. At steady state highway speeds the mechanical fan/clutch is not a big drag on the engine. I suspect any MPG gains would be found in surface street stop/go traffic but that is so variable it's hard to properly document any changes in MPG and determine the actual cause of the change. The only times I've had any problem running w/o a fan was in bumper/bumper traffic... .



I have also run dual electric fans on my CJ-7 while trying to sort out a cooling system problem. The electrics cooled the engine wonderfully - especially at Pismo Dunes. Just turn them on and leave them on - they pull the same amount of air at all times.



Biggest advantages of no fan or the electrics was the complete lack of noise and quicker warm-up.



Brian

 

[RHARVEY]

I would like to see what the difference would be on my 97 5 speed with 10k hung behind it pulling a 6% @ 90* temp outside. Coolant temps climb when I start using the hp going up long grades. Most of the pulls the temps will climb to 208*(fan clutch lock up temp) and it will either stay there or drop back some. But I have seen it go on up to 215 or a little higher. . Sure would like to keep things cooler. I have even looked into a custom aluminum radiator to see if that would help...





Rick

 

[MCummings]

my towing conditions must be quite different than his.

You don't know Scott very well do you :-laf



Scott has long passed the "$ per HP" consideration.



I have electric fans on my 12V, but it's a race truck, and doesn't pull. However, my 24V needs teh mech. fan 'cause I know it needs it.



It was 116* today the fan sure was roaring after even a brief stop in traffic.



I guess my reasoning to leaving the fan in place is a good working a/c system, and yo won't know when you have to have an insane fan. (stuck in mud, jockeying a trailer, etc. )





Merrick

 

[hammersley]

OK if these really saved FUEL and made more HP Don't

you think that due to the huge cost increases of diesel - the Class 8's would be all over electrics of some sort??? And they don't have the room problem we do! I mean a tenth of a MPG is BIG for them!

 

[NVR FNSH]

Don't a lot of Class 8's run an electric clutch fan like the Horton? Besides, I doubt a Class 8 is sensitive enough to the relatively minor power consumption of the fan to see any increase in MPG.



Brian

 

[MCummings]

When that lock-up clutch hits, you can see a huge drop in power with those trucks, Especailly in the older models with a too aggrgessive fan.



The '03 + trucks ahve a lock-up clutch type fan. It's somewhat of a half breed, but does it's job really well.



Merrick

 

[BigBadDodge]

Got them in, they work great installed a manual overide switch as well to turn it on at 100% when I hook to the sled. Next is the electric water pump then I can turn the motor off and have the fans and water pump circulating water through the block to cool her down between pulls Good thing I bought that HD-205-Amp alternator



BBD

 

[Jim Fulmer]

Same concept the drag cars use. That type of setup works great!



Jim

 

[bmoeller]

Don't a lot of Class 8's run an electric clutch fan like the Horton? Besides, I doubt a Class 8 is sensitive enough to the relatively minor power consumption of the fan to see any increase in MPG.



Brian

Never seen an electric clutch on them. Only viscous and the air operated clutches. Mostly Horton clutches that I have seen.



An air clutch is the only way to go on a Class 8. Most have a switch for manual or automatic engagement.





One thing I notices with the diesel fans. They said not to exceed 18,000#.



Correct me if I'm wrong, but, don't the 3rd gen truck have electric clutches on theirs?

 

[pwerwagn]

This isnt directed toward you scott, as I know your intentions differ from what most of this thread has lead to... .



I have elec fans on my 74 dodge, and noticed no difference in power, or mpg. It is a huge draw on the alt at low rpm, though. It is kind of a burden when winching, even at 2000+ rpm... . so I usually turn them off. They do help when loaded at low rpm, like below 2000 while pulling out a camper from the sand and stuff like that.



Just FWIW, someone on this forum tested fan and no fan at the 600hp level and only saw a 4hp difference (I think it was 4).