winkawak

https://themustangsource.com/forums/...ileage-540426/
With 15% off sale going on with whipple gen 3 im itchy to pull the trigger and get a supercharger finally!

bstang14

So, I have a Kenne Bell, not Whipple. if you have to ask if your gas mileage is going to suffer adding 200-300 horsepower, you probably should stay stock. Think about it......Add power....Use fuel. Simple. If I'm easy on the pedal, which I rarely am, I do a bit better, but average 13 around town. 18-20 highway extended trip. Before FI, I got 16-17 city, 23-25 highway. Seems about what you would expect adding a crap-ton of power.

winkawak

No i get that, what shocks me is with normal driving these whipple owners are getting 11mpg........while most sc out there mpg remain unaffected with normal driving might even see a increase in mpg.

Dino Dino Bambino

Since any supercharger puts a parasitic draw on the engine, gas mileage will be slightly worse than stock even if you go easy on the gas pedal. With a turbo set up however, you might see the same or slightly better gas mileage in light throttle, off-boost situations.
If you get on the gas pedal with forced induction, expect the gas mileage to drop like a stone.

danzcool

Well, with the 4.6L and 2-gen whipple I was getting right around 15 on average. given the displacement difference alone, the 5.0 would drop that to 13.8... go further and talk about how the heads on the coyote flow better, more airflow = more fuel used. WOT on whipple tune usually set for around A/F of 12.0 as opposed to near 14.6 on stock, so more fuel is ending up not burned with whipple in the name of safety for the engine when on it...
But I call it smiles per gallon, not miles per gallon.

bstang14

Very true. You can't forget that you are spinning a compressor all of the time. While you may be in boost bypass at light throttle, you still use engine power to drive the screws or rotors.

winkawak

Like i said i totally get the parasitic loss, but 5-6mpg drop with normal driving is crazy and unlike many other positive displacement. With spirited driving it would mean the mpg will drop as low as 5mpg lol. I asked around found many other who do have better mpg with slight drop about 1-2 mpg with normal driving which seem more normal. Also some claim its the whipple tune thats causing huge drop in mpg but idk.

bstang14

Honestly, I can see a 2-4 mpg drop overall, but bet on closer to 4 since your foot gains weight somehow with 700+ hp at the end of the wire. You may be able to adjust with the tune (leaner) but you are asking for problems. Most tuners will tune a bit on the rich side for safety.

danzcool

Any acceleration gets you into boost with a positive displacement supercharger, if you do a lot of city driving, that's going to be quite a hit. Highway driving you can remain out of boost for most of it other than passing. If you're concerned, get a vacuum/boost gauge, try to keep it in the vacuum section as much as possible you will get closest to stock mileage.

AK_Kayaker

This^^^^^