What are some modfications that will increase MPG?

[Popinski]

Forgive me if this isn't in the appropriate forums; I didn't know if it belongs to the maintenance or automotive general.


What are some modifications that would increase MPG and gain HP at the same time?

All I think of is:

-A good synthetic oil

-A good Tranny oil

-K and N Air filter(or equivalent)

-Free flowing exhaust.

 

[oilboy123]

I would say good synthetics front to back, proper air pressure. A clean non K&N air filter.

Free flowing exhaust would be an expensive modification.

 

[ionbeam22]

Proper tire pressure.

 

[Popinski]

Expensive or not, I would like to know.

I really don't consider proper tire pressure as a modification because that is basic owner's responsibility.

 

[dwendt44]

Ah, but most owner's manuals list tire pressures that are 'comfy' rides.
Mine are recommended for 30 psi; I run 35/36.
A slight gain in mpg and the tires last longer too.

My experience only: If you look at a pile of used tires, most show signs of underinflation.

 

[getnpsi]

Another nod to inflating 10-15% over sidewall number.

Buying a vacuum gauge or a scangauge can give immediate feedback to show the operator there are gains to be had in just driving style alone. the scangauge also lets you get a baseline and then you can modify your vehicle and see if there are improvements. Just timing signal lights on my habitual routes puts my city mpg about the same as my highway numbers in the Ranger.

 

[Quest]

shed some body weight (I'm not joking, consider how much a typical driver weighs)

Q.

 

[rpn453]

Reducing the minor losses in your exhaust system will improve fuel economy if you keep the diameter the same. But usually the diameter increases with exhaust modifications, so it would depend on whether the decrease in minor losses overcomes the loss of fuel economy from tuning the exhaust for higher power output.

The air filter should not affect fuel economy on a modern car unless it's very dirty.

 

[Turk]

There's an absolutely HUGE, detailed thread on this about a year ago - do a search!

 

[KrisZ]

Synthetics won't increase horese power, and to have more horse power you have to add more fuel, horse power and fuel economy just don't go together, if you increase one, you will decrease the other.

All the CAI and performance air filter manufacturers would have you believe that it is possible, but don't fool yourself.

Good maintenance regiment will keep your car in best shape possible and will return best possible mileage, that is the safest bet.

Now, if you really need more power, the best compromise will be a turbocharger, but again IT IS A COMPROMISE. If you stay off of boost the car should have good fuel economy (ex. on highway), and will have plenty power once you hit that boost (at the cost of fuel economy).

 

[Cup of Joe]

Stop rushing everywhere and drive slower.

 

[ZZman]

I don't know about horsepower and mpg but most mpg gains can be achieved by careful planned driving style.

 

[duaneb9729]

TaterandNoodles has the right idea, the best way to increase MPG is to adjust the nut behind the wheel.

That being said, i did buy a scan gauge about a year and half ago, and its a nice tool to help increase your mpg. I use mine to track daily MPG's, and it becomes a contest to see if i can better yesterdays "score". For myself it has ingrained some better driving habits, although i thought i was perfect before! smiles!

 

[JakeR22]

As far as physical modifications to be made to the car, basically nothing.

 

[CharBaby]

I use Cruise Control all of the time now. Not only do I get better MPG but, I reduce the chances of getting speeding tickets which are very costly these days. I remember when a speeding ticket cost about $50.00 in fines and maybe your car insurance would go up a bit. Now, speeding ticket fines are closer to $200.00 and your car insurance goes up for life.

 

[ARCOgraphite]

Install Narrower highway tread tires, a good alignment, and keep that tailgate up - open tailgate does not make an aerodymnamic difference on the highway and is a safety hazard to other drivers. Accelerate up to an efficient speed )45-50mph)quickly and into overdrive, and when there, keep the throttle opening as small as possible. Anticipate red lights so you will be rolling when they turn green again. If you are going to drive SLOW on the interstate - stay out of the passing lane(!!!), and get out of the way of long haul truckers if in the centre lane - these guys have a job to do and dont care about your fuel economy.

 

[BrianWC]

A word about cruise control, it may be best for fairly level roads. But on hills it can cost some gas mileage over non-cruise driving.

A Scangauge II is helpful if you have no stock instant mpg gauge. But, truthfully, unless you're considering an ongoing series of mods and want to gauge their effectiveness, the Scangauge can get superfluous. It took me all of maybe 2-3 weeks to figure out that for me and my driving, highly inflated tires, not relying on cruise on hills, lowering interstate speeds, and coasting for much longer distances up to stop signs were about the biggest practical changes I could make that didn't cost money.
After that, the Scangauge became a very expensive OBDII reader.

 

[froggy81500]

Originally Posted By: getnpsi
Another nod to inflating 10-15% over sidewall number.


you shouldn't exceed the sidewall number. the door tag number is another story. that is usually a compromise between fuel economy and comfort. My door tag says 30 or 32 but I run mine at 40. Max sidewall is 44 on these comfortreds. Better mileage with the higher tire pressure. Where it becomes a chore is when it starts getting colder out like right now, where large drops in ambient temps affect tire pressures. a 10*F drop usually nets a 1psi tire pressure loss.

 

[lexus114]

Originally Posted By: froggy81500
Originally Posted By: getnpsi
Another nod to inflating 10-15% over sidewall number.


you shouldn't exceed the sidewall number. the door tag number is another story. that is usually a compromise between fuel economy and comfort. My door tag says 30 or 32 but I run mine at 40. Max sidewall is 44 on these comfortreds. Better mileage with the higher tire pressure. Where it becomes a chore is when it starts getting colder out like right now, where large drops in ambient temps affect tire pressures. a 10*F drop usually nets a 1psi tire pressure loss.
Holy......

 

[StevieC]

Here is my list:

1) Synthetic in everything possible
2) Cooling system is clean and up to date on its maintenance
3) Proper tune up's with wires/plugs
4) Air filter that is free flowing. I like Amsoil EAA filters
5) Limited idling / warming up
6) A Top-Tier Fuel that doesn't contain Ethanol (if possible)
7) A Clean fuel system that is treated every 6 months with a PEA based cleaner
8) Regular use of a UCL like MMO or Lucas to keep the fuel system lubricated and help to seal piston rings during combustion.
9) Proper Tire pressure
10) Not carrying around weight that isn't needed. This could be junk or extra bench seats that are removable (like in a van)
11) Driving properly, doing the speed limit, taking off normal from a light and keeping rev's below 3K RPM
12) 20wt oil in your engine if OK'ed by your manufacturer
13) Minimizing your trips / routes by planning ahead and doing things in an order that saves you from double backing.
14) Prewarm the engine and/or oil with a block heater and/or an oil pan warmer 2 hours before going out in colder weather.
15) Keep your car clean and waxed/polished. This will limit wind resistance slightly.
16) Try not to run electrical accessories that aren't needed to reduce strain on the alternator which creates load for the engine.
17) Use your vents instead of your windows when going above 35MPH. Use your A/C above 50MPH for cooling if vents aren't enough. Open your windows any other time.