When can we expect a new engine in the F53?

[jharrell]

Originally Posted by vito.a

I agree that horsepower is often misunderstood. It is a mathematically derived number used in the early days of steam and gas engines to compare to a horse which was the common power source of the day. A dynamometer measures torque, not horsepower. Then the torque number is applied to the mathematical formula with rpm and a constant to get a number we call horsepower. Hope this helps!

You don't measure speed either, it is mathematically derived from distance / time using an rpm sensor and known wheel circumference. There are all sorts of measurements that are derived rather than directly measured, even the torque its self is not technically directly measured in a dyno, inertial dynos just measure rpm change with a known drum mass, while motor/generator drive dynos measure current and voltage produced.

The point being most measurements we rely on not direct and many are made up of component measurements. Horsepower is english unit of power, in the metric world they measure power in watts, just like we do with electricity, a car engine will be rated in kilowatts.

Power is what gets work done, torque is just force, you can apply torque and go no where, if there is rpm to go with it you move and that can be measured as horsepower. The engine makes horsepower, the transmission trades rpm for torque to effectively get the power to the wheels. Only the engine can make horsepower while a gearing can provide any torque required.

[jharrell]

Originally Posted by Jacjetlag

If your V-10 were to get 10 mpg on a good day.....

And the 7.3 with a 10 speed gets 12 mpg.....

You have a 20% improvement. Possible?

We'll see.

I track my mileage with an app, every fill up since purchased, my total average is around 6.7 mpg. I am very skeptical of anyone that claims doubles digits on a V10 Class A. I might get 7.5 mpg without the jeep and not running generator, and I run between 60 and 65 mph.

The only 10mpg in a class A is going to be the short and light 6.7 ISB diesel pushers. Maybe 10 in V10 with a very short and light and aerodynamic class C, but still skeptical.

So for me 20% would be 8 mpg, that would be great, but would be very happily surprised at that kind improvement, just not sure there is that much efficiency left on the table with the V10. Maybe if you get into the direct injection with a future 7.3l and get into some more aggressive lean burn and higher compression ratios.

[CJ7ole]

In the horsepower vs torque discussion, I always like to go back to the original definition of one horsepower: The effort needed to lift 33,000 pounds one foot in one minute. Torque is just one way to get back to that number. By that definition, 300 hp to the rear wheels ought to be able to allow a 33,000 pound coach to gain 300 vertical feet up the mountain in one minute. That would be 60 mph up a grade of 5.7%. We know that is not reasonable, so it points out all of the friction losses in the tranny, driveline, tires, bearings and wind. Are my numbers right?

[jharrell]

Originally Posted by CJ7ole

In the horsepower vs torque discussion, I always like to go back to the original definition of one horsepower: The effort needed to lift 33,000 pounds one foot in one minute. Torque is just one way to get back to that number. By that definition, 300 hp to the rear wheels ought to be able to allow a 33,000 pound coach to gain 300 vertical feet up the mountain in one minute. That would be 60 mph up a grade of 5.7%. We know that is not reasonable, so it points out all of the friction losses in the tranny, driveline, tires, bearings and wind. Are my numbers right?

I always like to think of Archimedes:

Give me a lever long enough and a place to stand and I will move the earth

I can create any amount of force required by increasing the length of the lever, I can move the earth, but very very slowly, a lever trades speed (time) for force.

A lawnmower engine can move your RV up a mountain with the correct gears, but very slowly.

To move your RV up a mountain more quickly, you need more power not more torque, you need the same wheel torque at a higher wheel rpm.

Torque is force, force can be multiplied by levers, gears are levers. Even inside the engine the length of the lever created by piston stroke changes the torque of the engine.

The final horsepower at the wheels needed to go up a grade at a certain speed is a little involved, it's about weight and air resistance and frictional losses, but its mostly a power to weight problem, while cruising on flat ground has more to do with air resistance. There are calculators that can give you an idea of how much power is needed, this is a very good guide by CAT on the subject:

[DryCreek]

To quote a scholar nearly as old as Archimedes:

"There's no replacement for displacement."

[tiffy2000]

Originally Posted by jharrell

I track my mileage with an app, every fill up since purchased, my total average is around 6.7 mpg. I am very skeptical of anyone that claims doubles digits on a V10 Class A. I might get 7.5 mpg without the jeep and not running generator, and I run between 60 and 65 mph.

The only 10mpg in a class A is going to be the short and light 6.7 ISB diesel pushers. Maybe 10 in V10 with a very short and light and aerodynamic class C, but still skeptical.

So for me 20% would be 8 mpg, that would be great, but would be very happily surprised at that kind improvement, just not sure there is that much efficiency left on the table with the V10. Maybe if you get into the direct injection with a future 7.3l and get into some more aggressive lean burn and higher compression ratios.

I have an older MH, 2000 Tiffin 33 (35 ft long) V10 about 16,000 # with my load of stuff and at times I have got 10 mpg but averaged 8.5 over about 1500 miles last year from NH to PA and back with other trips in there. I do think the older coaches do a little better on mpg , not sure why.

[mtofell]

Does anyone have any idea when Ford will release the HP and torque ratings? I've read a lot about the engine but can't recall them promising anything. I know a lot of us are waiting anxiously.

[jharrell]

Originally Posted by mtofell

Does anyone have any idea when Ford will release the HP and torque ratings? I've read a lot about the engine but can't recall them promising anything. I know a lot of us are waiting anxiously.

The closest thing to a promise is from here that I have seen:

https://www.svtperformance.com/threa...ction.1170924/

So to not bury the lead, we've heard from several sources that the internal goal for the 7.3L Godzilla engine is 450HP. It may come in a little higher or lower, but that seems to be the figure Ford engineers were initially shooting for. No word yet on a torque figure, but my guess is somewhere around 500lbft. One thing is for certain, big power is going to be made on the low-end of the RPM range. For the current applications the 7.3L is slated for, stump-pulling grunt always on tap is a standing order.

GM just released their 6.6 gas for trucks at 401 hp and 464 lb-ft, so you know the 7.3L is going to have to be more than that. I would like to see 450 hp of course but would be happy at 425 hp, I think around 500 lb-ft either way.

[mtofell]

Originally Posted by jharrell

The closest thing to a promise is from here that I have seen:

https://www.svtperformance.com/threa...ction.1170924/



GM just released their 6.6 gas for trucks at 401 hp and 464 lb-ft, so you know the 7.3L is going to have to be more than that. I would like to see 450 hp of course but would be happy at 425 hp, I think around 500 lb-ft either way.

Thanks... that's great info.

I have to wonder if Ford will de-rate it a bit initially to leave some room to make a few tweaks and up 10-15hp in future years? Of course, they went backwards with the current V10, admittedly due to taking readings at different RPMs for some emission thing.

I'm excited to see this engine come to market and for the next few years to see how it changes gas coaches. Anything near 450hp with a 10spd tranny is going to be a total game changer to say the least.

The GCWR and towing numbers will particularly interesting with the new setup.

[Rvlegaleagle]

The article link dated February 7, 2019 above was awesome to read

Although my wait to finally order the 3401 Bay Star has been taking much longer than originally planned...the 2019 brought the counter top over the stove...and now 2020 is bringing all this to the chassis... it seems good things do happen to those that wait

Happy Easter all!

[Jacjetlag]

Impressive numbers that would really sell.....


450 hp
500 foot pounds

And would an aluminum block/steel sleeved version make a decent "Boss" Mustang...yes, indeed.

[CJ7ole]

Slap a turbo on it. Mega Ecoboost...

[Highway 4x4]

The 7.3 and a 10 speed trans would really turn heads in a class A. 10MPG towing a Jeep would make me sign papers.

[twinboat]

Originally Posted by Highway 4x4

The 7.3 and a 10 speed trans would really turn heads in a class A. 10MPG towing a Jeep would make me sign papers.

With a 10 speed, you would never get any torque out of the engine, before it shifted.

I don't think you'll see it in heavy motor home chassis.