new mustang ecoboost

[crashnzuk]

The wife and I bought a new eco boost mustang when they came out in ‘15. It was a 6 speed performance pack. It was fun, but neither of us got anywhere near the claimed mileage, and it didn’t make fun noises either. We were getting 20-22 in mixed driving, and on long haul interstate going 80 it got 27-28. The kicker was the drivers seat killed my back. We traded it in at 1 year and 10k miles on a ‘16 Challenger 5.7L 6 spd shaker R/T. The Challenger easily does 20 in mixed, and 25-26 on the super slab, cruise on 83 mph. For reference, the 2001 mustang bullitt 4.6 5 spd that we had before the eco-mustang got 20-22 mixed and 25-26 highway with 100 less hp and probably 800 lbs less than the challenger. I had higher hopes for the mustang but it just didn’t deliver for us.
Travis..

[Vansquish]

Originally Posted by hayden55

I don't believe anybody can get 40 mpg out of a v6 mustang unless they are going 55 mph. The 11-14 v6 mustangs got more like 16 around town and 28 on the highway for the auto.

To be clear, the Ecoboost Mustang has a 2.3L turbo I-4 motor, not any of the 2.7, 3.0, or 3.5L twin-turbo V6 motors that Ford/Lincoln offer in other applications.

The I-4 is very closely related to the Focus ST motor, and the L3-VDT motor in the Mazdaspeed3, Mazdaspeed6, and Mazda CX-7. Having run a lifetime average of above 32mpg on the highway in my nearly 3600lb, AWD, very short-geared (70mpg is just under 3100RPM) Mazdaspeed6, I can say that I could definitely believe a more modern incarnation of the engine with less driveline losses could achieve closer to 35 or 40mpg under the right conditions.

[logix]

Originally Posted by crashnzuk

The wife and I bought a new eco boost mustang when they came out in ‘15. It was a 6 speed performance pack. It was fun, but neither of us got anywhere near the claimed mileage, and it didn’t make fun noises either. We were getting 20-22 in mixed driving, and on long haul interstate going 80 it got 27-28. The kicker was the drivers seat killed my back. We traded it in at 1 year and 10k miles on a ‘16 Challenger 5.7L 6 spd shaker R/T. The Challenger easily does 20 in mixed, and 25-26 on the super slab, cruise on 83 mph. For reference, the 2001 mustang bullitt 4.6 5 spd that we had before the eco-mustang got 20-22 mixed and 25-26 highway with 100 less hp and probably 800 lbs less than the challenger. I had higher hopes for the mustang but it just didn’t deliver for us.
Travis..

I'd assume since your here ur probably not a bad driver as well. I'm actually impressed with that milage out of the Challenger

[crashnzuk]

Originally Posted by logix

I'd assume since your here ur probably not a bad driver as well. I'm actually impressed with that milage out of the Challenger

I think I’m pretty good. Tried short shifting it, letting it rev out with light throttle, brisk accel up to cruise speed, didn’t seem to matter. The lie-o-meter in the dash always claimed 24-26 mixed. I was hoping for a fun car that got good mileage, especially on road trips since we travel the vast spaces of the west fairly often. It just didn’t deliver for us. On the other hand, the challenger is what I would consider very good for what it is. The manual cars don’t have cylinder deactivation either, the autos get better hi way mpg than mine. Even then, I have no desire for an automatic equipped car. We actually would have bought a charger if it were available with a stick
Travis..

[ALS]

I've owned Turbo (2.1L and 2.3L) Volvo's from 1981-2009 and I know how to get the best mileage out of one. Rules one and two, stay out of boost, keep the RPM's under 2,500, and you'll get the best fuel mileage.

What people don't understand on modern turbo's is when the boost goes up so does the extra fuel being dumped into the cylinders. Not just to compensate for more air being pumped into the engine but that extra fuel is also used to cool the cylinders.

You might be driving a 2.3 liter Eco Boost but spool the turbo up and you might as well be driving a NA 3.5 liter as far as the amount of gas being pumped into the cylinders.

You were asking between the two which car would be better? I would go with the Mustang for the simple reason that if you planned on using the car on the highway it is far easier to swap out the rear gears for better mileage. I think it comes with 3.31 rear gears and you could swap those out easily for a set of 3.08's.

The problem I have with the 1.5L Honda is the motor is undersized for that car. Toyota learned that lesson with the Prius 1.5 liter and went to the 1.8 liter and upped the fuel mileage and power in the third generation.

My opinion for what it is worth is that 1.8-2.0 liters is the sweet spot for power and economy NA or Turbo. Go below the 1.8L range with Direct injection and Turbo charging and you're only looking for trouble in the "long run" with engine reliability.

[hayden55]

Originally Posted by ALS

I've owned Turbo (2.1L and 2.3L) Volvo's from 1981-2009 and I know how to get the best mileage out of one. Rules one and two, stay out of boost, keep the RPM's under 2,500, and you'll get the best fuel mileage.

What people don't understand on modern turbo's is when the boost goes up so does the extra fuel being dumped into the cylinders. Not just to compensate for more air being pumped into the engine but that extra fuel is also used to cool the cylinders.

You might be driving a 2.3 liter Eco Boost but spool the turbo up and you might as well be driving a NA 3.5 liter as far as the amount of gas being pumped into the cylinders.

You were asking between the two which car would be better? I would go with the Mustang for the simple reason that if you planned on using the car on the highway it is far easier to swap out the rear gears for better mileage. I think it comes with 3.31 rear gears and you could swap those out easily for a set of 3.08's.

Yup. Ford for this reason. You can go to 2.73s easily on any model. Only use FRPP gears though if you do. Also, the easy part went out the window with the IRS models.

[ALS]

You have to be careful how high you go on the gearing or you'll be causing more problems with your fuel mileage especially with a Turbo. Go too high in the gearing and you'll be in the Turbo more than you want. The slightest incline and the motor will be boosting.

Most car manufactures bump the gearing up by one set to improve the drive ability for a slight decrease in fuel economy. My experience with Volvo's is if the car came with 3.73's in an automatic the best economy would be with 3.54's. If it came with 3.54's with a manual transmission then the 3.31's would be the best for economy.

There are gear calculators out there when you can play with gearing for the transmission as well as the differential and tire sizes. You can tune the rpms to vehicle speeds with these online calculators.

With an Eco Boost four cylinder, manual transmission Mustang, I'd be looking at rpms running around 1750-1800 at 65 mph for the best fuel mileage. With a V8 Mustang you can run 1200-1300 rpms at 65 mph because the engine produces so much torque at low RPM's it isn't an issue.