any ways to save gas?

Scarrell · Post by **Scarrell** » Thu Apr 27, 2006 10:38 pm

you could put it in nuetral at a stop light.. some say that saves a little gas.. but who knows.. driving slow and not being in a rush ofcourse will help...

Jonathan · Post by **Jonathan** » Thu Apr 27, 2006 11:08 pm

You have to improve the efficiency of the engine, basically. That would be a higher flowing air filter, MAF/MAP, upgraded exhaust, head modifications if you were crazy about it. You have to keep the engine in it's most efficient range as well. An engine will get the best gas mileage around it's torque peak, but unfortunately with the current trend of spinning anemic 4 bangers to extremely high RPMs, your peak efficiency is typically far above the point where aerodynamics becomes a large factor. Basically, the aerodynamics of the vehicle will hinder gas mileage more than the engine's efficiency would help it. That's a lot of the reason that displacement can help you get better gas mileage, to an extent of course. It's also the reason that most of the older 80s 4 cylinder vehicles got the same or better real world gas mileage than today's equivalent vehicles.

Realistically, though, gas mileage is dependant primarily upon weight. Next is aerodynamics, then you have the engine. That's assuming the engine isn't designed to be a high performance fire breather. You can't overdo power and you can't underdo power. Too little power and the engine stresses so hard that you hinder mileage. Too much power/displacement and the engine will consume more fuel than it needs.

Post by **GlassWolf** » Fri Apr 28, 2006 12:22 am

Scarrell wrote:you could put it in nuetral at a stop light.. some say that saves a little gas.. but who knows.. driving slow and not being in a rush ofcourse will help...

How do you figure?
In gear, the car sits at a lower RPM than in neutral at idle when stopped.

Mithrandir · Post by **Mithrandir** » Fri Apr 28, 2006 4:29 am

I need get like 80 more hp out of my sunfire, cause it works fine with one person driving, then 2 is sucks a little more 3 it starts breathing heavy and getting chest pains and 4 it has a heart attack or figure a way for it to make more torque and hp at lower rpms lol

Post by **GlassWolf** » Fri Apr 28, 2006 10:39 am

supercharger

lotas · Post by **lotas** » Fri Apr 28, 2006 1:16 pm

Aren't car engines like 17% efficient or some insanely low number?

Post by **GlassWolf** » Fri Apr 28, 2006 5:24 pm

about 85% if I recall if you're talking VE on a n/a engine.
You can actually achieve over 100% VE with forced induction.

ridr4lif · Post by **ridr4lif** » Fri Apr 28, 2006 5:47 pm

Im not trying to argue with you Glass, but i did a quick search and found this on "how stuff works.com"

The efficiency of a gasoline-powered car is surprisingly low. All of the heat that comes out as exhaust or goes into the radiator is wasted energy. The engine also uses a lot of energy turning the various pumps, fans and generators that keep it going. So the overall efficiency of an automotive gas engine is about 20 percent. That is, only about 20 percent of the thermal-energy content of the gasoline is converted into mechanical work.

Ryan from Ohio · Post by **Ryan from Ohio** » Fri Apr 28, 2006 5:52 pm

Nitrogen in your tires

THats the latest fad around here at Belle Tire

Mithrandir · Post by **Mithrandir** » Fri Apr 28, 2006 8:05 pm

GlassWolf wrote:supercharger

find me one for under a grand