Quote:
Originally Posted by Chance
That’s already happened. Ford switched from the 6.8L V10 to 7.3L V8 last year on the larger E-Series Cutaways. The smaller Transit Cutaways presently get 3.5L V6, either naturally aspirated or turbocharged. There’s not much “engine” middle ground in Ford Cutaways.
My initial “guess” is that the new 6.8L V8 will probably be an aluminum-block engine to keep weight down for F-150 and particularly the Mustang. If based on 7.3L Godzilla V8, it would likely require smaller cylinder bores to increase thickness between cylinders. That “could” explain displacement reduction from 7.3 to 6.8.
Anyway, in my opinion the 7.3L is a bit too large for smaller Class Cs built on E-350 to achieve optimum fuel economy. In time maybe a 6.8L V8 will find its way into E-Series but I wouldn’t expect it. Still, for motorhomes getting 10+ MPG on the highway, a smaller engine should help a little. Problem is that it’s only about 7% smaller which isn’t much.
Accuracy of my guesses on 7.3L V8 were dismal, so these are probably off too.  |
To the last sentence, no worries. I like your posts.
Aluminum will (and should) getter a smaller bore because it's harder to dissipate the heat. Heat transfer happens quicker in an aluminum block where steel retains the heat within the cylinder and heat transfer is slower, allowing the coolant ports to work their magic but increase the wear on pistons, rings and oil. Smaller bores in aluminum sort of have the same effect - keeping the cylinder walls cool (relatively) and engine light weight.
You can reduce both scenarios with a larger radiator and the right thermostat, but that's a trade off as well. More metal and more water.
The aluminum trade-off may be curb weight, GVWR and GCWR, which goes up. If it doesn't become a zero sum game, they can use a sturdier frame and increase the payload but not the GCWR because the increased frame weight will take it's toll. Much like 4WD vehicles. Add a font drive train and it increases weight, reducing towing capacity over a 2WD of the model.
I like the what they did with the eco-boost in the GT40. Hell of a lot of horsepower but not too much need for torque. Change up the rear axle ratio and do a little ECM programming and you might have a motor that'll carry a 24klb motorhome down the road at decent performance and gas mileage.
Just thinking on my part. Keep well.
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