350 HP ICE vs. 350 HP Diesel?

I don't think anyone has talked about weight. Typical F53 gasser max is 26000 lb gcvwr. Diesels can easily get to 60000 lbs loaded up.

So let's look at weight/torque. So 26000lbs/450ft-lbs=57.77lbs of motor home mover per ft lb of torque.

A diesel might be 1250 ft lbs of torque or more. So 60000/1250 = 48 lbs of class a diesel pusher moved per ft lb of torque. Take my class c is 19000/420=45

Each can do his own Coach. It would be interesting to see everyone's numbers.

MrUsa I generally agree with your statement, one just has to have the wallet to enjoy that nice ride and amenities and unless we can get Obama to subsidize our lifestyle ,cost is a factor to most of us.

All this talk of HP and torque is only one small part of the equation. Diesel pushers are built better, on better chassis, with better suspensions, and better amenities. They ride better, handle better and are more comfortable. Like most things that provide more benefits, they cost more to buy and to own. I defy anybody to drive them both and then say that they would take the gasser if the cost were the same. There is ONLY one reason to chose a gasser over a diesel: cost savings. If you want save money get the gasser. If you want the best experience regardless of cost, the diesel is the only way to go.

PastorCharlie wrote:

wny_pat wrote:

tinkerer wrote:
the hemi has a lot of power but is constantly hunting for right gear because it's torque curve is small. I really don't care what other say about gassers as I go by the seat of my pants and the diesel wins hands down, JMHO.;)

And there in lays the answer! The torque curve of a diesel covers a much wider RPM range that the gas engine does. The diesel requires less shifting when going up a hill because of the wide torque curve.

Why do they put 20 plus gears in the diesel rigs?

Simple the big rig diesels have a very narrow HP curve. When looking at the performance of an engine it is the HP curve that counts.


"There is a new supercharged 6.2 hemi due out this year. It will be close to 680-700HP"

If this statement is true the 6.2 hemi will outperform the current big three stock diesels by a very large margin. This will be true under all conditions including high elevations.

wny_pat wrote:

tinkerer wrote:
the hemi has a lot of power but is constantly hunting for right gear because it's torque curve is small. I really don't care what other say about gassers as I go by the seat of my pants and the diesel wins hands down, JMHO.;)

And there in lays the answer! The torque curve of a diesel covers a much wider RPM range that the gas engine does. The diesel requires less shifting when going up a hill because of the wide torque curve.

Why do they put 20 plus gears in the diesel rigs?

I like Rex Haul's answer. As said, you have to buy it for what you expect to do with it. Take care of it and if it ever fails to meet your needs, sell it off and cry a little when she leaves.

Matt

JetAonly wrote:
Also, FWIW there are several 350HP diesels. In Cummins probably a B and a C motor. There is also a 370ISL. Then there is at least one Cat, a C7, maybe the 3126 also?

If we are going to change engines, there is a new supercharged 6.2 hemi due out this year. It will be close to 680-700HP and will probably smoke the tire on any vehicle up any hill. It might be available in the Ram 1500. 6.2 Dodge hemi :B

Also, FWIW there are several 350HP diesels. In Cummins probably a B and a C motor. There is also a 370ISL. Then there is at least one Cat, a C7, maybe the 3126 also?

I'm not very smart when it comes to all of the technical points made in the debate that will never end "gas vs. diesel". I do understand the difference between the two and the performance characteristics of each. What I do know for sure though is presently my V10 gas rig does everything I need from it for the type of camping we do; weekend warrior with one or two long trips a year. However, when the time comes that we would either full time (sad waiting for retirement)or spend considerably more time out on the road enjoying this spectacular country or ours my first move would be a nice used diesel for all the reasons stated previously and my opinion the superior quality of materials from chassis up through the coach.

rmighty wrote:
OK, newbie here and aspiring RV'er. What comments can be made about the advantages/disadvantages of a 350 HP internal combustion engine vs. a 350 HP diesel engine in a class A camper (assuming all other variables are equal)?

You are asking the wrong question.

All this flailing about HP and TQ proves nothing. The Motor Trend test prove that HP wins the quarter mile test. So unless you are bracket racing your MH, how does that relate to the MH experience?

The important questions are: Does it have a floor plan your wife likes? Does it have air leveling, Aqua-Hot or a tag axle. Are you using it for camping or full timing? What is your budget? Are you towing more than 5k?

When you've answered those questions you will find a motor that will be suitable for what you want to do already installed in the chassis.


IMHO

wolfe10 wrote:
No question-- HP is a HP. But, how many are willing to run their gasoline engines at peak HP RPM for long periods? Diesels, no problem.

I will:) Boats run these engines wide open all the time, but not everyone is running a 502.

wny_pat wrote:

tinkerer wrote:
the hemi has a lot of power but is constantly hunting for right gear because it's torque curve is small. I really don't care what other say about gassers as I go by the seat of my pants and the diesel wins hands down, JMHO.;)

And there in lays the answer! The torque curve of a diesel covers a much wider RPM range that the gas engine does. The diesel requires less shifting when going up a hill because of the wide torque curve.

The fact is that just the opposite is true. Gas truck engines will have a nearly flat torque curve from about 1800 RPM to about 4000 RPM, much broader than a diesel that won't turn over 2500 RPM. That is why diesels have tons of gears.

Basically you are right but for the wrong reason. What it comes down to is where your reserve HP is achieved. Because of the lower torque of a gas engine, its reserve HP is achieved by turning high RPMs. This means one often must downshift to access the reserve power. In a high torque engine, all of the reserve HP is achieved simply by pouring more fuel into it, without changing the RPM much. This means a diesel gains very little by downshifting.

So to answer the OP's question, quite simply, if both engines are set up optimally, they should accelerate and pull hills very similarly. In other words, if you measure performance by your speedometer, the performance will be identical, regardless of he weight or hill. HOWEVER, because high torque engines have all their reserve power available without increasing the RPM, this means the engine does not downshift when pulling hills. This can make the diesel easier to drive, even though the ultimate power and flat out acceleration is the same.

BTW: The reason diesel is often used in trucks is because of efficiency. The combination of high compression, and self ignition is more efficient than using spark plugs. As a mater of fact, GM and Honda are experimenting with a gas engine that works like a diesel, due to the increased efficiency of the burn. The concept of higher torque is only a design choice, and has little to do with a fuel type.