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Old 08-01-2019, 03:51 PM   #81
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I predict there will be improvements over the first several years of production that will make me happy to keep my current rig a few years longer .
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Old 08-01-2019, 06:55 PM   #82
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Here is a bit more power and torque data.

F-250 and F350:

430 HP @ 5,500 rpm
475 lb-ft @ 4,000 rpm


Larger trucks, F53, F59, and E-Series:

350 HP @ 3,900 rpm
468 lb-ft @ 3,900 rpm

https://media.ford.com/content/fordm...ty-pickup.html



It seems the engine can rev higher than many expected, although for heavier commercial trucks and RVs, Ford limits power to 3,900 RPM.

It will be interesting to see if there is a real physical difference, or if itís strictly a reporting thing on paper due to government regulations.

These ratings also explain different redlines on similar instruments. The ~ 6,000 RPM must be for pickups, and roughly 5,200 ~ 5,300 RPMs for heavier trucks and RVs.

One thing many will like is roughly +400 lb-ft of torque starting at 1,500 RPM.
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Old 08-01-2019, 07:01 PM   #83
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P.S. ó ďThe upgraded E-Series will also feature the 7.3-liter V8. An optional calibration intended to help customers reduce their fuel consumption will also be offered; more information will be made available at a later date.Ē


The ďeconomyĒ version for E-Series seems to be targeting improved fuel economy, not lower initial cost.
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Old 08-01-2019, 07:30 PM   #84
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Engine longevity might be a reason why they are limiting RPMs on the big rigs. Running high weight at high rpms in commercial vehicles might cause problems over the "long haul".
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Old 08-01-2019, 09:14 PM   #85
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So in the F53 weíll see effectively the same horsepower and torque we have now in the 6.8L. Good to know!
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Old 08-02-2019, 10:06 PM   #86
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Originally Posted by Pete'sMH View Post
So in the F53 weíll see effectively the same horsepower and torque we have now in the 6.8L. Good to know!
Youíre correct ó not much difference in ďrated numbersĒ.

I hope, and expect, that in normal driving the new V8 will feel more refined, and pull significantly harder also.

At the maximum torque point on the curve, the V8 makes 362 HP (475 lb-ft at 4,000 RPM), while the 3-valve V10 makes 263 HP (460 lb-ft at 3,000 RPM).

For what itís worth, I watched interview with Ford engineer (link below) who worked on engine, and as I suspected, the 3,900 RPMs for ďbothĒ power and torque are due to emissions regulations. Sounds like fuel economy may suffer significantly if above 3,900 RPMs (no surprise there), so they have to limit the commercial rating.

So yeah, the F-53 maximum rated numbers arenít that different, but I expect the way the engine feels will be very different. If nothing else, I hope that the inherent balance of a V8 will make the engine much quieter and less prone to vibration in that 3,900 to 4,000 RPM range.

Another advantage to new V8, according to Ford engineer towards end of video, will be superior engine braking compared to V10, which will help with descending in mountains. The brief EPA comment on how regulations affect ratings is at around 8 minutes of video. We have to ignore the exuberance of the interviewer.


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Old 09-20-2019, 08:40 PM   #87
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Ford released information regarding the two ďtunesĒ for the 7.3L V8 when installed in E-Series.

The Economy version has lower power and torque, both at lower RPMs. Iíd have to see just how much more fuel efficient it is before giving up that much power.
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Old 09-20-2019, 08:48 PM   #88
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Interesting...
With more power under your "loud" foot: you don't have to work the engine as hard to get the job done.
That can result in BETTER fuel economy!
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Old 09-20-2019, 10:17 PM   #89
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You should tell Ford powertrain engineers how wrong they are.
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Old 09-20-2019, 11:13 PM   #90
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Nahhh...
Then they'd just try to explain insurance to me!
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Old 10-07-2019, 09:42 PM   #91
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Ford is starting to release more info on new 7.3L gas V8 capabilities. I noticed a few data points that are most likely misprints, but most information is consistent with other/previous information.

Trailer towing as high as 21,200 pounds should meet a lot of needs. There is also data on 10-speed transmission gear ratios, axle ratios, etc. Price for the 7.3L V8 is just over $2,000 over base 6.2L V8 (from a Ford window sticker).

One item thatís promising is the higher GVWR of up to 12,400 pounds for Single Rear Wheel F-350, although that requires 4X4 option. The 4X2 is limited to 11,500 pounds.

https://media.ford.com/content/dam/f...Tech-Specs.pdf


I can see the SRW F-350 4X4 with 12,400 GVWR making a nice expedition-type off-road motorhome.
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Old 02-06-2020, 08:47 PM   #92
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check this video out on the 7.3 in rv's and delivery trucks https://youtu.be/aEkfiqHi8uY
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Old 02-07-2020, 09:59 PM   #93
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Originally Posted by jimmyzshack View Post
check this video out on the 7.3 in rv's and delivery trucks https://youtu.be/aEkfiqHi8uY

Thanks for video comparison. Those guys act a little immature at times regarding toys they test, but are fun to watch nonetheless.

As expected the V8 does outperform the V10 ó no surprise there. Letís hope Ford didnít rig the test by giving new V8 an unfair advantage over the V10. I expect it was a fair race/comparison for most part.

I liked the sound of the V8 more than the V10, so curious how it will sound under E-Series doghouse.

What I liked best about video was discussion about high motorhome center of gravity. I hope people think about that and the impact it will have on handling. Larger sway bars should be loved by many on this forum.

Whatís still missing is fuel economy difference between V8 and V10.
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Old 02-10-2020, 06:02 PM   #94
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There is a lot of new information starting to come out on new engine and its performance potential.

From the same guys, this video shows a Super Duty 3/4-ton pickup pulling a 16,000-pound horse trailer up a steep grade above 10,000-feet elevation in Colorado. It beat the new Chevy 6.6L V8 truck engine by a significant margin.


https://youtu.be/4HiR9dxvGLY




Also, there are numerous videos of the engine being taken apart showing internals, and some already hot rodding with new cam and intake to increase power just below 600 HP.

In one video it was disclosed that engine bore spacing is 4.53Ē, or 115 MM, which is same as 6.2L V8. The Ford technical man who seems very knowledgeable said deck height was 9.65Ē, which is 245 MM. He said that there isnít much opportunity for much longer stroke at that deck height; not that we need more than 7.3L.

It was interesting that the new engine is only about 2 inches wider across the valve covers compared to an old 351 Windsor small-block V8, and much narrower than a Coyote 5.0L V8.

Itíd be great if Ford could make the E-Series doghouse a bit narrower to increase foot space, although I doubt they would even if possible due to cost.
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Old 02-10-2020, 07:19 PM   #95
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Iíve not really been keeping up on this as Iím not in the market. But I note that the new engine makes less torque and at a higher rpm than the 6.8. 30 more hp than the f53 version but Iím not seeing numbers to make me want to field test a new engine for Ford. Perhaps the mileage will be better but itíd take a lot to make me want to get one yet. Of more interest to me would be the new chassis.
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Old 02-10-2020, 07:44 PM   #96
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Yes, at 50 MPH in forth gear the engine was spinning at 4,200 RPM. That is higher than I feel comfortable running a big V-8 or V-10.
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Old 02-10-2020, 08:09 PM   #97
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Running 4,200 RPM on an engine with a 6,000 RPM redline wouldn’t concern me one bit, particularly since it was producing huge amounts of power. Plus it “sounds” like it can take it, unlike my V10s which sound like they are begging for me to back off throttle. Just my personal opinion on the sound — have never liked V10 noise.

I’m not sure where the “less torque” than V10 is coming from. If we are going to compare apples to apples, the V10 dyno ratings are significantly lower. Even at rated torque, 468 is more than 460, or 420 of E-Series. And again, that’s a commercial heavy-duty dyno rating at 3,900 RPM.

This engine may very well be flawed (maybe too early to tell), but the power it’s making is much higher than the factory V10 ever made.



P.S. — By the way, I went up that same mountain pass and was able to stay at speed limit of 60 MPH with my van which probably weighs about the same as the pickup, and half as much as the 16,000-pound trailer. That they were able to average almost 60 MPH while pulling a trailer that heavy is surprising to me. I didn’t use full throttle, but had I been pulling a trailer half that weight, my V10 would have struggled. No doubt about it.

I’m not trying to promote this new V8; I have nothing to gain from it. But I’d love to have one in my next RV unless they suddenly find a flaw in the design. On paper and now on road it beats the V10 in every way that is important to me.
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Old 02-11-2020, 10:22 PM   #98
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Is that based on RWD Explorer? The general shape is very similar.

Ford a while back announced upgrades to the motorhome chassis. It would not surprise at all if they are on display.

Iím also interested in what Ford may do for smaller motorhomes. While Iím intrigued with the 7.3Lís potential, it may be far more power than smaller Class As like Axis/Vegas may need, or smaller Class Cs on E-350. If that engine can make over 400 HP, I donít know how they would get enough cooling underhood in an E-Series Cutaway. Thatís a lot of heat.

I still think the F-150ís 5.0L V8 would be plenty of power for smaller motorhomes. It puts out much more power and torque than the old 5.4L V8 that was used on smaller Class Cs.
I had the old 5.4l gas engine, was O.K. in pulling my Coachman trailer. But, was a real dog in pulling my 9500# Crossroads trailer. I traded up to the 7.3L diesel and never looked back. I believe the new 7.3L gas will be very welcome to users of the 6.8L V10.
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Old 02-12-2020, 05:17 PM   #99
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I had the old 5.4l gas engine, was O.K. in pulling my Coachman trailer. But, was a real dog in pulling my 9500# Crossroads trailer. I traded up to the 7.3L diesel and never looked back. I believe the new 7.3L gas will be very welcome to users of the 6.8L V10.

I agree. It will just need time to win some of them over.

Itís interesting to look back in time ó the post you quoted was from over a year ago before we had power and torque numbers for 7.3L gas engine. Now that we know a bit more, I still think itís too much engine for many smaller motorhomes.

The towing test was for 8 miles, at 7% grade, up to 11,000-foot elevation. Given that those conditions are an extreme we rarely encounter, and that the new engine pulled a 40-foot horse trailer weighing 16,000 pounds, for a combined weight of around 24,000 pounds, and at an average speed near the limit of 60 MPH, Iím still thinking itís more than many smaller motorhomes need.

If installed in an Axis 24.1 or small Class C weighing half that much (around 12,000 pounds), what would we accomplish under those severe mountain conditions? Save less than one minute while using half of available power? Not much to be gained from all that power in my opinion.

Thereís nothing wrong with having more power than needed, but in case of new 7.3L V8, I think it may be too large to optimize fuel economy in smaller motorhomes like Axis 24.1 or lighter and more aerodynamic Class Cs and B+.

I hope the ďEconomyĒ tune proves me wrong, but for now still think a 5.0L V8 is about all the power needed for smaller rigs that wonít be towing heavy trailers in the mountains.

Donít get me wrong, Iíll happily buy the new V8 if I find the right motorhome, but would trade a little power for added fuel economy if it was a choice. I just donít see this engine delivering 12 MPG in a small MH. Hope Iím wrong though.
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Old 02-12-2020, 09:11 PM   #100
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I agree. It will just need time to win some of them over.

Itís interesting to look back in time ó the post you quoted was from over a year ago before we had power and torque numbers for 7.3L gas engine. Now that we know a bit more, I still think itís too much engine for many smaller motorhomes.

The towing test was for 8 miles, at 7% grade, up to 11,000-foot elevation. Given that those conditions are an extreme we rarely encounter, and that the new engine pulled a 40-foot horse trailer weighing 16,000 pounds, for a combined weight of around 24,000 pounds, and at an average speed near the limit of 60 MPH, Iím still thinking itís more than many smaller motorhomes need.

If installed in an Axis 24.1 or small Class C weighing half that much (around 12,000 pounds), what would we accomplish under those severe mountain conditions? Save less than one minute while using half of available power? Not much to be gained from all that power in my opinion.

Thereís nothing wrong with having more power than needed, but in case of new 7.3L V8, I think it may be too large to optimize fuel economy in smaller motorhomes like Axis 24.1 or lighter and more aerodynamic Class Cs and B+.

I hope the ďEconomyĒ tune proves me wrong, but for now still think a 5.0L V8 is about all the power needed for smaller rigs that wonít be towing heavy trailers in the mountains.

Donít get me wrong, Iíll happily buy the new V8 if I find the right motorhome, but would trade a little power for added fuel economy if it was a choice. I just donít see this engine delivering 12 MPG in a small MH. Hope Iím wrong though.
I want an Axis that can do wheelie's
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