Terrible fuel economy
#21
12-03-2011, 02:54 PM
#22
12-04-2011, 02:05 AM
E-Fan - hands down... Relatively low initial cost and it'll give a solid 2 MPG and about 14 more HP free'd up at the rear wheels.
Tuners do a good bit for performance and a side benefit might be a small mpg gain, but the consensus is the PERFORMANCE tunes and 93 octane gas does better than the so-called "MPG Tunes" which all tend to de-tune the engine requiring more throttle for the same effect, thus negating any MPG gains they may otherwise provide...
BTW fellas - I have ABSOLUTELY no problem with debates or guys giving opposite view points on a subject. Hell, plenty of people don't agree with some of my posts. BUT it's gonna be done in a respectful way on this site with no bashing, name calling, taunting, etc. OK???
Tuners do a good bit for performance and a side benefit might be a small mpg gain, but the consensus is the PERFORMANCE tunes and 93 octane gas does better than the so-called "MPG Tunes" which all tend to de-tune the engine requiring more throttle for the same effect, thus negating any MPG gains they may otherwise provide...
BTW fellas - I have ABSOLUTELY no problem with debates or guys giving opposite view points on a subject. Hell, plenty of people don't agree with some of my posts. BUT it's gonna be done in a respectful way on this site with no bashing, name calling, taunting, etc. OK???
Do you have a little more info about the E-fan you speak of? I'm kinda curious about it and what it does. I'm fairly new to all these performance mods but trying to learn
#23
12-04-2011, 06:38 AM
3rd Gen Ram Moderator
I asked pretty much the same thing a little while back. Here's the C/P of Hammer's response, which answered my questions pretty well:
Clutch type fans are just pure-out inefficient. First of all the fact that they are driven by a belt off the crank means that a portion of energy produced by the engine must be used to drive the clutch fan. This means lost horsepower. Just simply removing the clutch fan with it's parasitic drag can free up as much as 25 HP depending on the vehicle.
This gives a huge benefit as far as fuel economy is concerned. Make more power at lower RPMs means having to give it less throttle. Less throttle = less gas used.
The big issue I have with clutch fans is that they spin in relation to engine RPM - the faster you go, the faster the belt moves, the faster the fan spins. Well think about it - the time you need the fan LEAST is when moving down the open highway at 75 MPH, when the wind is being forced thru the radiator by simple motion. It's when you are stuck in traffic on a hot day or crawling along off-road when you need the fan the most and with a clutch fan, these are times the clutch fan is barely moving. An e-fan moves air at it's rated capacity whether you are sitting still or doing 120 mph.
Realistically, on a Dodge Ram you can expect about a 14-18 RWHP gain with an efficient e-fan. MPG gains will depend on where/how you drive. Because a clutch fan is most parasitic at low RPMs when the engine has to work harder to move it, you'll typically see the most benefit from switching to an e-fan in city driving conditions. Expect about 2-3 mpg gains in city driving and a slight gain on strictly highway driving conditions.
As far as the type, there are two ways to go. Many guys save money by piecing together their own "kit" and start with a fan from a junked car such as a Ford Taurus or Lincoln Mark VIII.
Others purchase a full kit where everything you need is included in the box, such as the Flex-a-Lite 180 Extreme that I have. (The new FLex-a-Lite Kit is model 183 which replaces the 180 model). It's an extremely light fan with a very low AMP draw, so a larger alternator is not needed.
Their instructions are good and about the only place I deviated from them is that I kept my stock shroud and mounted the fan inside of it with screws thru the side. I felt this guided air over the radiator fins better...
Installation guide:
http://www.flex-a-lite.com/auto/183-99183.pdf
This gives a huge benefit as far as fuel economy is concerned. Make more power at lower RPMs means having to give it less throttle. Less throttle = less gas used.
The big issue I have with clutch fans is that they spin in relation to engine RPM - the faster you go, the faster the belt moves, the faster the fan spins. Well think about it - the time you need the fan LEAST is when moving down the open highway at 75 MPH, when the wind is being forced thru the radiator by simple motion. It's when you are stuck in traffic on a hot day or crawling along off-road when you need the fan the most and with a clutch fan, these are times the clutch fan is barely moving. An e-fan moves air at it's rated capacity whether you are sitting still or doing 120 mph.
Realistically, on a Dodge Ram you can expect about a 14-18 RWHP gain with an efficient e-fan. MPG gains will depend on where/how you drive. Because a clutch fan is most parasitic at low RPMs when the engine has to work harder to move it, you'll typically see the most benefit from switching to an e-fan in city driving conditions. Expect about 2-3 mpg gains in city driving and a slight gain on strictly highway driving conditions.
As far as the type, there are two ways to go. Many guys save money by piecing together their own "kit" and start with a fan from a junked car such as a Ford Taurus or Lincoln Mark VIII.
Others purchase a full kit where everything you need is included in the box, such as the Flex-a-Lite 180 Extreme that I have. (The new FLex-a-Lite Kit is model 183 which replaces the 180 model). It's an extremely light fan with a very low AMP draw, so a larger alternator is not needed.
Their instructions are good and about the only place I deviated from them is that I kept my stock shroud and mounted the fan inside of it with screws thru the side. I felt this guided air over the radiator fins better...
Installation guide:
http://www.flex-a-lite.com/auto/183-99183.pdf