will a supercharger increase gas mileage?
- posted
18 years ago
will a supercharger increase gas mileage?
That is a little vague, but yes it can. It can also cost you fuel mileage if not set up properly. You wont save as much as you spend on the supercharger though. Clay
No, it will decrease mileage, i.e., worsen fuel economy. Added horsepower from a blower comes at a price.
Why?
I understand that the blower increases air in the engine causing a better explosion with the same amount of gas. Is that not the case?
If I drive my truck the same as I do without a blower will it have better mileage with a blower?
No its not the case. If the amount of fuel is not increased the fuel air ratio will be way to lean.
Whitelightning
So does MPG stay about the same then for the same type of driving?
Usually it will get worse. What kind of supercharger are you asking about? Belt driven or turbo.
Al
It could increase, but not to likely. Horsepower/torque need to be enough at cruise RPM to keep the engine from lugging too much. If you are always working your engine hard, the addition of forced induction could increase power output enough so your engine wont work as hard. Therefore your economy could increase a good bit. If you want to add it to a daily driver, chances are strongly against any increase in economy.
No because the blower takes power even if not in use.
When in use it packs more air into the cylinder, therefore more gas can be injected too, resulting in more power.
Where it works nice is in mountain driving. Pulling over a 13000 foot mountain pass where the air is very thin you can get performance that is near that of sea level but at a price of more fuel consumption.
Forced-induction driven by the belt is a Supercharger. Forced induction driven by the exhaust is a Turbocharger. He's asking about belt-driven...
Expanding a little on what Whitelightning said, the air:fuel ratio for gasoline engines is pegged at 14:1 (I've kept it at integers). This is also called the stoichiometric ratio.
Whether or not you turbocharge or supercharge, which increases the charge/volume of air being forced into the engine, and with the ratio being "pegged" at 14:1, hence the fuel figure will also increase to maintain the ratio (manually or electronically measured/metered).
The supercharger requires horsepower to compress air, not to mention the parasitic losses involved.
If you need Ooomph! to accelerate, tow or climb, the supercharger will give that to you, but, again, it comes at a cost.
Franko
superchargers are belt or gear and/or belt and gear
look at it this way. a super charger is belt driven. it is driven by the motor to spin a fan that forces air into the intake. it aactually takes horsepower to create more power. a turbo charger works off of your exhaust. using already moving air, cooling it down, and forcing the cooled air into the intake. it dosent take anything power wise to create mass amounts of horsepower. a turbo will give you very good gas mileage. a supercharger will not. you also have to look at what kind of power you want. a supercharger will give you all kinds of torque and low end power, good for going through the mountains or four wheeling. a turbo will give you power on the top end, wich is good for hiway driving and towing. they make both turbo and supercharger kits for the 350. personally, i would turbocharge my truck before i supercharge it. its "free" horsepower.
nothing is free...a turbo costs HP as it does cause a significant amount of back pressure on the engine. a turbo doesn't cool anything, actually it heats the hell out of the intake charge. the aftercooler/intercooler (if so equipped) is what cools things back down.
-Bret
A supercharger robs power and lowers fuel economy any time your manifold pressure is low. Such as at cruising speed. I say this because a supercharger only adds pressure (greater then the normal 1 atmosphere) to the top side of the throttle plate. Making this pressure takes power. All of that power goes into heating the air unless you open the throttle to let that pressure push extra air and gas into the engine to make power.
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