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16.8 MPG What the F#@!!


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not necessarily true. the vf40 spools very quickly and its very hard to stay out of boost even in city driving. while in boost, you consume as much fuel as a 5.0L engine since the stock boost target is around double atmopheric preassure which effectivly doubles our engine's diplacement. I know there is more to it than that, but for all intesive purposes, in boost our engine consumes fuel like a v8, if not faster. A slower spooling turbo would allow better city mileage since you say out of boost more at lower RPM.

 

 

hmmm....so if it spools quickly, then effectively this car should have zero to very little turbo lag, but people complain about it all the time here....

 

and if what you are saying is correct, then theoretically speaking, if a person driving an LGT lived in Manhattan and say only drove around Manhattan and the accompanying 4 boroughs and only drove in traffic-like conditions, then their turbo should have a very short lifespan.....correct?

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hmmm....so if it spools quickly, then effectively this car should have zero to very little turbo lag, but people complain about it all the time here....

 

and if what you are saying is correct, then theoretically speaking, if a person driving an LGT lived in Manhattan and say only drove around Manhattan and the accompanying 4 boroughs and only drove in traffic-like conditions, then their turbo should have a very short lifespan.....correct?

 

 

you talk as if the turbo wears out like brake pads. Turbos should last as long as the engine no matter how much you use them if maintaned properly. But you are mising the point. poor mpg in the gt is due to the difficulty of staying out of boost since the vf40 spools at 2500rpm or so. I dont know why people complain about lag. my vf40 lights up lightning quick, and i pay for it by getting 16mpg city during my commute to work from NJ to L.I.C queens. If i try really hard, i can keep it out of boost and get 19-20 mpg city, but it requires me to contantly control my throttle inputs and to shift early. The bottom line is the gt is made for performance, not fuel economy. 16mpg or less in city and stop and go traffic is certianly possible, and if you mod you car and dont tune for it, the mpg can get even worse. So it you want economy, dont get a car with a turbo unless its a diesel.

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^ Turbos work great for fuel economy but the economy comes from a different angle. A 2.5l engine weighs a lot less than a V8 or even a big 6. Also because it is smaller, weight can also be saved in chasis size. If one refrains from blasting from light to light and keeps the RPMs low, staying out of boost lets the engine perform like the 4 cylinder it is (though it does have lower compression which takes away some efficiency). What we can't get away from is the added weight and drive train losses caused by the AWD system.
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A slower spooling turbo would allow better city mileage since you say out of boost more at lower RPM.

 

+1

 

I've been averaging anywhere form 19.5-22mpg in 100% city driving with my VF30 which full boosts at 3300 compared to seeing 16.5-19mpg when I had my VF40.

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I'm seeing 21.3mpg over the last 300 miles (2 weeks). Some spirited driving as I'm learning the new car, but mostly mixed suburban & Stop & go with maybe 25% highway...

 

Edit: Just filled up my tank this morning and ran the true numbers on my last tank of gas. I got 21.59mpg. As I near the end of my break-in period gas mileage seems to be improving, but it might also be the K&N panel filter - LOVE the sound of that addition and it dampened the effect of the stutter as well!

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After 6250 miles on my '07 Spec.B (6MT transmission), I am at 21.0 MPG. That's with about 20% highway / 80% "spirited" suburban (mostly short-trip) driving. I drive it in S# mode almost always, and tend to accelerate pretty hard when traffic conditions permit.

 

No mods on this car, though I'll be snatching up the stage 1 AP as soon as it comes out, in an attempt to get rid of the damned stutter that the reflash didn't fix. :mad:

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Dude, you put on BIGGER WHEELS. That means for the same speed, they are turning slower! Therefore:

 

your speedo will read lower than before

your odometer will turn slower

any mileage calc based on odometer will be wrong

 

(Also the wheels might be heavier and tires might have more rolling resistance.)

 

I can't believe this thread is 4 pages, lol.

 

Very well said....

 

 

Flavio Zanetti

Boston, MA

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