stangdude81

I stopped to look......ok, drool.....over a Shelby GT at a dealer the other day and noticed something funny. While looking at the performance additions, it appears the only real power adders were a Ford performance pack of an intake, tune, and FRPP Stingers out back. This should bump it up to what I figure to be around 330hp at the flywheel, give or take. When I looked at the sticker, I noticed there is an EPA mandated "GasGuzzler" charge of $1000. Is this possibly why Ford has the GT's tuned down to 300hp? What is the justification for having this surcharge for purchasing a vehicle which has so little gas consumption difference from a basic GT?

hammeron

https://mustangforums.com/m_2882173/tm.htm

it's a great question

SonicBlue05GT

just curious, but why wouldn't it get better gas mileage since it breathes easier?

timothyrw

uh.... what was the question again?

i got diverted to break.com

RodeoFlyer

doesn't it come with the drag pack? - 4.10 gears?

EmperorOfChicken

nah, power pak and handling pak, comes with 3.55s.

05gtdriver

It's because the combined mpg(city+hwy avg. divided by 2)is less than what's determined as acceptable fuel mileage(I believe over 21.5 combined mpg is not considered a gas guzzler). The Shelby GT's combined mpg are not up to this level and is subjected to being taxed, but only $1K, the GT500, with it's worse combined mpg, is taxed $1,300. Although the GT's combined mpg is 21(for stick cars), so why aren't we being taxed?

Black GT

You are on the right track, but your equation is wrong (too simplified).

This is the equation used to determine the gaz guzzler tax: (1/(.495/City MPG + .351/Highway MPG)) + .15

With the equation, a Mustang GT with 17 mpg city & 25 mpg highway would have a combined fuel economy of 23.32 mpg. This is above the minimum of at least 22.5 mpg, hence no gas guzzler tax.

Also, the mpg values used in the equation goes by the EPA published value, which may or may not be the same as other published values.

05gtdriver

Thanks for the correct info Black GT, I knew it was something in that direction, but was taking a stab at the methods used. That formula is pretty intricate, huh?

Drew47000000

I think its safe to say in most cases, whenever you gain horsepower you will pay for it by using more fuel. Im not sure this works for every scenario, but it just makes sense that if the car is producing more output power wise it must be burning more fuel to produce it...
[sm=bounceybounce.gif]
On another note, has anyone noticed the headlight switch on the shelby GT's. It still pulls out like our GT's do to activate the fog lights. But the Shelby GT's dont have fog lights, so what happens when you pull on the switch?? I would kinda think that ford just reused the same switch from the Mustang GT, but why wouldnt they have used the V6 light switch without fogs? Is it because shelby just buys the GT's straight from ford then does there mods and doesnt worry about the light switch?