WyoTraveler wrote:
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My 2008 F250 V10 has about 360 HP & 457 FT LB of torque. Towing a 4500 lb TT I got about 9 mpg. Of course torque developed at higher RPM. Even with about same HP & a little more torque I don't go zipping over mountain grades. I think the new F150 is designed more for east coast flat lands where it probably does very well. Doubt it pulls mountain grades with power to spare.
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You forget that the EcoB line of engines are all turbos. So they don't loose power at higher elevations like naturally aspirated engines do.
As a result, the 3.5L EcoB would have more power than the V10 at higher elevations. There's a formula for % power loss with elevation for naturally aspirated engines that is floating around here somewhere.