Big v10 or small v10

I'm really not sure. I have been told there are two v10's a big v10 for class a and a smaller one for the c's and b+. the class a Winnebago 30a has a 6.8 v10 362 hp. Is any one sure of the size of our engines?

Hey Billy -

Am rushing out the door this AM, but off the top of my head, both the same motor.  If I remember correctly, "we" have a 2-valve per cylinder head, while "they" have 3 valves.  Significant gain in horsepower, less impressive gain in torque - but same displacement, same basic hamburger patty, only the "bun 'n fixin's" are different.

E-series chassis vs the F53 chassis(?) (super-duty) I think?

Even some of the Cummins and MaxxForce diesel engines of a given displacement in Class A's have different states of "tune", different "buns" to more closely match anticipated duty cycle of the chassis, whether via valves, cams, compression, injection specs, turbos, etc.

I'll check more closely later today and see what else I can dredge up.

I have been told the same about the valves.

Here’s a Ford link where you can compare both chassis:

https://www.fleet.ford.com/showroom/specialty_vehicles/Motorhome.asp


Class A 6.8 V-10: 362 hp/4750 rpm

Class C 6.8 V-10: 305 hp/4250 rpm


Class A 6.8 V-10: 457 lb-ft/3250 rpm

Class A 6.8 V-10: 420 lb-ft/3250 rpm


Granted, it can get really complicated really fast - both horsepower and torque figures make their own characteristic contributions to forward propulsion.  But generally speaking, torque’s contribution is “grunt” – what it is that gets you moving, and what factors most greatly in terms of acceleration.  If you look at some Class A diesel’s, you’ll often find horsepower ratings often barely breaking 300 hp, yet torque ratings often climb into the 600+ lb-ft realm.

Horsepower, again speaking generally, is the force that more accurately predicts your ability to continue propelling a given load at a given speed – at least until the next hill or grade, at which point your “load” requirements change, and torque takes over once again.

I our case, I wouldn’t engage in Class A envy, Billy.  Chances are when comparing overall performance between the Phoenix Cruiser units against any other V-10 Class A chassis, (or even typical Class C’s with the lower rating for that matter) you’re well out ahead in performance and mileage.  The 8% increase in torque is entirely eaten up by the heavier chassis and loaded weight of a Class A.  Weight consumes torque.

In the case of horsepower, the 16% increase may seem like a lot, but that is also entirely consumed as well – by shear wind resistance and drag.  Wind resistance created by sheer frontal area, drag created not only by the rear house walls’ greater dimensions, but the larger gap between chassis and the road surface.

Thing of what it is you’re pushing AND dragging through the air:


Phoenix Cruiser/B+ = Shed Door

 Class C = Garage Door

Class A = Barn Door

So while the 3-valve Class A motor does produce more power, its advantage is entirely consumed by the model’s attributes it’s powering.

On the other hand, who doesn’t like more?  Yet more also gets you less.  Less fuel economy and less “quiet” – that engine has the same peak torque rpm rating, but has to run at higher rpm to produce that extra horsepower.  And less cockpit comfort - the Class A motor will running “hotter” in the E-series.

Heat both saps power and intensifies the wear and aging of the motor and auxiliary components and systems.  The relatively cramped E-series doghouse only further intensifies those issues.

Whether on van or pickup chassis, we’ve all noted in the last few years we’ve gone to relatively giant and up-sized front grilles.  While yes, they make a given truck look more “macho” or “butch” – their greater benefit is in service of more efficient motor cooling.

In this case, the Styling AND Engineering Departments both get what they want.

Folks:

It is my understanding that 362 HP V-10 will never make it into and E-cutaway chassis; it is all about the heat,  period; the engine bay is just to small to get rid of the heat build up and therefore the smaller rated V-10.  Thanks

I was told the same..

I guess I have two questions.  Has anybody actually felt limited by the power of their V10 powered PC motorhome?  I have a E350 based 2551 and tow a Chevy HHR, admittedly a smaller combination than many of you have, but have criss crossed the Canadian Rockies without feeling underpowered.  Yes, the cars can run away from me, but I routinely found myself passing all the big rigs on the climbs.  Also, if you really want more power, wouldn't it be cheaper to use some hot rod kits like Banks, who claim their kits run cooler with more power, than contemplate changing out your engine?  Just wondering??

Jerry

Pc 3100 with Honda crv. I very much considered the total banks system but looking for a small truck and $4k would go a long way. The part I do not like is pressing on the gas and feeling like I just stepped on a wet pile of cow s----. Very slow response.

But then again, Billy -

You ARE actually piloting an approximately 14,000#, 7-ton "pile".

But as I've said before, who doesn't like "more"?

But for every benefit, there is yet again, a trade-off.

JC Said:

>>>>  “I guess I have two questions. Has anybody actually felt limited by the power of their V10 powered PC motorhome?”

It would depend on what your expectations are when it comes to the driving dynamics of a 5-9 ton vehicle, or vehicle combination.  What you think it is that is “responsive” when piloting what is, in essence, an entire “domicile” and personal vehicle, out upon the roadways.

And should also be compared to the same weight and/or combination performance vs that of a Class A, or a Class C for that matter.

Billy -

Assuming your CRV is even a two-wheel drive vehicle, you'd still be quite hard-pressed to find a "truck" or any compact "pickup" of any modern vintage whose gross weight is any less than your CRV.

You can go "lighter", but then it would be for "B" cars, such as the much smaller Toyotas (Corolla's, Matrix's or certainly, the Yaris'), or the Honda Civic's (or certainly the Honda Fit), etc.

You're not likely to find any lighter vehicle that matches the CRV's interior accommodations at a lighter weight.  Uless you're willing to put up with less passenger space and less cargo space otherwise.

In my case, power is something of a moot point as on long trips we usually tow our Chevy HHR which has a limit of 65MPH.  My PC 2551 handles that quite well.  What I question about wanting/needing more horsepower is what for?  The fact that a toad really needs auxillary brakes reinforces the fact that for many motorhomes braking power is more a concern than acceleration or top speed.  Returning to our high school physics class, we remember that kinetic energy is equal to 1/2 mass times velociy squared.  You put a heavier engine in, the mass goes up.  You drive faster, the kinetic energy goes up by the square of the velocity increase.  If you gotta slow that big beast down fast, the faster you're going the more braking energy it's gonna take. I'm just saying you want enough power to feel you can maneuver safely on the highway, but these things were never meant to be hot rods.

Jerry

Has anybody actually felt limited by the power of their V10 powered PC motorhome?

Our 2007 E350 with 6.8L-V10 towing our Jeep Wrangler (Correction ...LIBERTY...senior moment), I feel has more power than needed.  I wonder if I could have gotten by with the 5.4L-V8 option and save some gas.

I suppose it depends on where you are coming from.  Our first motor home was "Very" under-powered, yet we did fine going 57 mph on the open road and slowing down in the up-hill climbs.  A little 2.4L-L4 (96hp) engine handling 4500 pounds was a bit of a stretch.