mods increasing gas mileage
02-12-2006, 11:27 PM
#11
2nd Gear Member
Join Date: Feb 2006
Location:
Posts: 302
RE: mods increasing gas mileage
02-13-2006, 12:56 AM
#12
4th Gear Member
Join Date: Nov 2005
Location: Michigan
Posts: 1,235
RE: mods increasing gas mileage
I've noticed an increase in gas milage with each bolt on I got. Bone stock was 15-16mpg. Now with all my bolt on's and before 4:10's I was getting 22mpg in the city. Now w/ 4:10's I'm hitting 19-20mpg...
02-13-2006, 01:04 PM
#16
3rd Gear Member
Join Date: Jan 2006
Location: Deerfield, VA
Posts: 674
RE: mods increasing gas mileage
Gas mileage and mods is a tricky question. The only one I agree with for sure, is the UDP's, I expect maybe a 1/2 mpg gain. As for CAI and plenum I can't tell much of a difference, meaning that I haven't lost any mileage. I did at first, but that was due to romping on the car more. Once I settled down, my mileage picked up. Now as far as the added air increasing mileage, No. For instance in winter, air is colder, more dense, it requires more fuel for the proper stoichometric rate of 14 to 1. Yes you gain more power, more fuel, less mileage. The same is true modding the induction system, more air, more fuel, more power, less mileage, the MAF sees to that. The only way you might keep the same mileage is to drive easier, use that extra power to accelerate the car without revving it. If I want mileage (with stock gears) I shift at 2500 rpms, takes self-control but you will get decent mileage. My best mileage always is in summer, when I'm not burning excessive fuel warming my engine, and the gasoline formulation seems optimal. I got 30 mpg stock with my car on the hwy in summer. I hope to get 28 with the mods this summer, right now, in winter, driving easy, I'm getting 25, but so is our 4cyl Escape too. The Escape usually gets 29-30, in the summer too. My feeling is if you tune with a hand-held tuner, thatb probably would have the biggest effect on fuel economy.
John
John
02-13-2006, 03:02 PM
#17
4th Gear Member
Join Date: Aug 2004
Location: Philadelphia, PA
Posts: 1,654
RE: mods increasing gas mileage
Mods that will help gas milage (even if mildly)
1.) Weight reduction (Rotating weight makes the most difference)
An aluminum driveshaft
Lightweight smaller wheels
Two-piece light-weight rotors
A light weight clutch, flywheel, pressure plate (especially one with a smaller diameter)
General weight reduction such as lighter seats, or removed seats, remove the spare tire/jack, etc...
2.) Belt drag
Electric water pump
Underdrive pulleys
Convert to non-power steering (manual rack)
Turn off your A/C
3.) Aero Dynamics
Some splitters should help the car move better with less drag or lift.
4.) Transmission/Gears
Some transmissions have really small ratio overdrive gears which increase gas milage.
Swapping out your rear gear for one with a little less pickup may lower your highway RPMs and increase milage BUT, it might also make the car a pig around town and actually worsen the gas milage (since you'll have to downshift to go anywhere).
5.) Fluids and friction
I've heard some people have noticed some gas milage benefits from using high end fluids in their transmission, differential housing, and engine.
6.) Engine rebuilds
Higher compression and lighter weight engine components should increase gas milage.
7.) Computer Tune
This is really important. Having the right tune and Air/Fuel tables is extremely vital to gas milage. Running too leen will cause unsafe engine problems and a loss of performance. Running too rich will also hurt performance and it will kill gas milage. The same goes for timing. Too much = engine problems, Too little = worse gas milage.
The tune also dictates other important factors like your idle RPMs and the shift points for automatics.
8.) Heat soak
If your intake temps are too hot, you'll end up with performance and gas milage issues. This is why heat extractor hoods and Cold Air intakes might actually have a benefit.
9.) Spark plugs and ignition
If your plugs don't fully ignite the air/fuel mixture, you're sure to experience a loss in performance and miles per gallon.
It may be worth while to check them for fouling or upgrade to better plugs. There are some products like a plasma-booster which are meant to help you burn the mixture more thouroughly.
As far as most exhaust and restriction stuff is concerned, remember that your fuel injectors will provide additional fuel for any extra air that moves through your engine. This does not improve gas milage but rather just provides better power potential. Most fuel efficient cars do not flow very well because more air = more gas = worse fuel economy.
Things that hurt gas milage:
Boost and any low end torque/hp killers like long-tubes or cams.
Gears will hurt highway miles/gallon
Overdrive crank pulley, 200 amp alternators, and weight will all hurt
A final note:
Driving habits have quite a bit to do with this as well. Keeping off the throttle as much as possible, maintaining lower highway speeds. Driving in higher gears (lower RPMs if you've got a manual). Letting off the throttle and coasting into a stop sign or red light. Don't leave the car idling for long periods of time. Don't use the A/C unless you need to. Keep power consumption down.... All of these factors along with regular maintenance will help you get the best gas milage your engine has to offer.
1.) Weight reduction (Rotating weight makes the most difference)
An aluminum driveshaft
Lightweight smaller wheels
Two-piece light-weight rotors
A light weight clutch, flywheel, pressure plate (especially one with a smaller diameter)
General weight reduction such as lighter seats, or removed seats, remove the spare tire/jack, etc...
2.) Belt drag
Electric water pump
Underdrive pulleys
Convert to non-power steering (manual rack)
Turn off your A/C
3.) Aero Dynamics
Some splitters should help the car move better with less drag or lift.
4.) Transmission/Gears
Some transmissions have really small ratio overdrive gears which increase gas milage.
Swapping out your rear gear for one with a little less pickup may lower your highway RPMs and increase milage BUT, it might also make the car a pig around town and actually worsen the gas milage (since you'll have to downshift to go anywhere).
5.) Fluids and friction
I've heard some people have noticed some gas milage benefits from using high end fluids in their transmission, differential housing, and engine.
6.) Engine rebuilds
Higher compression and lighter weight engine components should increase gas milage.
7.) Computer Tune
This is really important. Having the right tune and Air/Fuel tables is extremely vital to gas milage. Running too leen will cause unsafe engine problems and a loss of performance. Running too rich will also hurt performance and it will kill gas milage. The same goes for timing. Too much = engine problems, Too little = worse gas milage.
The tune also dictates other important factors like your idle RPMs and the shift points for automatics.
8.) Heat soak
If your intake temps are too hot, you'll end up with performance and gas milage issues. This is why heat extractor hoods and Cold Air intakes might actually have a benefit.
9.) Spark plugs and ignition
If your plugs don't fully ignite the air/fuel mixture, you're sure to experience a loss in performance and miles per gallon.
It may be worth while to check them for fouling or upgrade to better plugs. There are some products like a plasma-booster which are meant to help you burn the mixture more thouroughly.
As far as most exhaust and restriction stuff is concerned, remember that your fuel injectors will provide additional fuel for any extra air that moves through your engine. This does not improve gas milage but rather just provides better power potential. Most fuel efficient cars do not flow very well because more air = more gas = worse fuel economy.
Things that hurt gas milage:
Boost and any low end torque/hp killers like long-tubes or cams.
Gears will hurt highway miles/gallon
Overdrive crank pulley, 200 amp alternators, and weight will all hurt
A final note:
Driving habits have quite a bit to do with this as well. Keeping off the throttle as much as possible, maintaining lower highway speeds. Driving in higher gears (lower RPMs if you've got a manual). Letting off the throttle and coasting into a stop sign or red light. Don't leave the car idling for long periods of time. Don't use the A/C unless you need to. Keep power consumption down.... All of these factors along with regular maintenance will help you get the best gas milage your engine has to offer.
