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DonTom
09-05-2007, 07:35 AM
Of today's (last seven years or so) larger engines, are some more reliable than others?

Any engines I should avoid in my next RV? Any especially good large engines I should be looking for? Seems finding a diesel in a small RV is rather hard to find, so all options are open until I decide what to buy.

The Ford ten cylinder gasoline engine seems to be a rather common RV engine. It's 500 CI IIRC. But did I hear that GM also makes a ten cylinder or some other engine that's about 500 CID? I think I heard this engine was not allowed to be sold in CA, because it doesn't meet smog requirements. I think I heard about it in the RV forum years ago, but not sure. But if not sold in CA will not be an issue, because it will be licensed in NV anyway. What's the largest gasoline engine GM now makes and is it any good?

And same question for diesels.

And the same question for trannys in these larger heavier vehicles.

-Don-

mrblanche
09-05-2007, 07:52 AM
This discussion was going on in our T bucket forum lately, too.

The 10-cylinder engines have been discontinued, and longevity seems to be at least one factor. Broken cranks seem to be a problem with both the Dodge and Ford versions, and I wonder if this isn't due to the heavy loads they've been subjected to.

It all depends on how old you want to go, of course.

DonTom
09-05-2007, 08:36 AM
"The 10-cylinder engines have been discontinued, and longevity seems to be at least one factor. Broken cranks seem to be a problem with both the Dodge and Ford versions, and I wonder if this isn't due to the heavy loads they've been subjected to."

I had no idea. Are there any decent gasoline engines for RV's these days?

-Don-

DonTom
09-05-2007, 10:54 PM
If the 10 C engine has been discontinued, how come we can still find the 6.8L V10 in new 2008 RV's such as here:

http://www.winnebagoind.com/products/winnebago/sightseer/specs.php

-Don-

MikeHalloran
09-05-2007, 11:32 PM
What's the largest gasoline engine GM now makes and is it any good?

I think your GM parts counter can get you a big block V8 (396/427/'rat') motor up to 502 ci.

The engine has been in regular production since 1965. An awful lot of people seem to think it's good enough.

http://en.wikipedia.org/wiki/Chevrolet_Big-Block_engine

DonTom
09-05-2007, 11:55 PM
"I think your GM parts counter can get you a big block V8 (396/427/'rat') motor up to 502 ci."

The 26 foot RV (that's as small as Class A's come) from that website comes with a Ford 8.1L (340 HP, 494 CID) engine. It has less power than the smaller V-10, which I assume means more torque. The longer RV's with the V-10 come with a 5 speed auto tranny, but the V-8 comes with a four speed auto tranny. I assume the larger RV's with the smaller V-10 engine more than make up for the lower torque with the extra low gear in the tranny.

Is the Ford 8.1L V-8 supposed to be a good reliable engine?

That just might be our next RV.

-Don-

Eric
09-06-2007, 07:53 AM
In the early '70s, Cadillac offered a 511 cubic inch (as I recall, might have the displacement off by a few ccs) 8.2 liter V-8 in its biggest boats - which weighed around 5,000 pounds fully loaded.

Today's biggest SUVs have V-8s in the 6 liter range and weigh around 6,000 pounds or so.

I'm just peeing in the breeze here, because I know little about RVs, but it seems to me that todrag around something that weighs twice or more as much, you'd want an engine with extremely high torque that was very, very tough.

While those big V-8s do make some decent torque - my guess is no more than 450-500 lbs.-ft. of it - and at fairly high RPM.

A diesel would give you much more torque 600-700 lbs.-ft (maybe more) at just off idle. It would also be a fundamentally stronger engine (super HD block/bottom end especially).

If it were me, I'd go diesel - for the durability and the power (torque).

DonTom
09-06-2007, 10:06 AM
"If it were me, I'd go diesel - for the durability and the power (torque)."

So would I, until I found out they are never put in small Class A RV''s (bus style RV).

In larger Class A RV's they like to put the diesel engines in the rear so you don't have to hear the noise.

And it takes up room, about ten feet, when compared to an engine in the front. In the front, they don't mind using gasoline engines because they make less noise. In a small RV, you don't have that ten feet to waste.

And I cannot even find diesel engines in the small Class C's (the large van type of RV).

Seems I will have to go with gasoline and 26 feet long, if I want a Class A.

Class A's have a lot of advantages. Stronger frame. etc., Can safely tow 5,000 lbs and a 500 LB tongue weight. That means I can safely carry my DR200SE on the rear, even though it's behind the rear axle.

-Don-

DonTom
09-06-2007, 10:12 AM
"It would also be a fundamentally stronger engine (super HD block/bottom end especially). "

Are rods less likely to break in a diesel than in a gasoline engine? If so, why?

-Don-

Eric
09-06-2007, 11:01 AM
"It would also be a fundamentally stronger engine (super HD block/bottom end especially). "

Are rods less likely to break in a diesel than in a gasoline engine? If so, why?

-Don-


Diesels are typically "over-built" and designed to withstand tremendous loads, even abuse. While some gas engines are built with HD parts, many are not.

DonTom
09-06-2007, 09:40 PM
Eric,

I just found some information about diesels in the RV forum. Seems gasoline might be better for the way our RV will be used. Please read this and let me know what you think:

http://www.rvforum.net/index.php?option=com_content&task=view&id=168&Itemid=63 (http://www.rvforum.net/index.php?option=com_content&task=view&id=168&Itemid=63)


-Don-

mrblanche
09-07-2007, 12:13 AM
Let me respond better later, but my first advice is this, after seeing zillions of motor homes all over the country.

Go to a few parking lots and measure the total length of two parking spaces. The reason I suggest this is that that is about the maximum length you should go for, so you could park in most parking lots, including restaurants, etc.

Then, keep in mind that you want a chassis with the shortest possible overhang in the rear. Many manufacturers have a huge rear overhang, because it's cheaper to build an RV that way, and it makes it more maneuverable. But it creates a lot of trouble with "tail swing," and dragging that overhang can leave you stuck in all sorts of driveways (and I've seen it happen).

DonTom
09-07-2007, 12:39 AM
It will be 26 feet regardless, as that's the smallest Class A RV made.

As for the overhang, why is it cheaper to build that way?

Our next RV might be the 26 foot model of the SightSeer, but won't be new. Perhaps at least five years old, but won't buy for at least a year as it would not get used until then anyway.

Here's what it looks like:

http://www.winnebagoind.com/products/winnebago/sightseer/ (http://www.winnebagoind.com/products/winnebago/sightseer/)

-Don-

mrblanche
09-07-2007, 10:03 AM
A short chassis is cheaper than a long one. And the Sightseer has a pretty long overhang back there. I wouldn't want to be back there going down the highway on a windy day or over a rough road.

In addition, the first question I would ask a dealer is how much it would cost to replace the windshield, and how long it would take. The more "unique" the profile, the more it will cost and the longer you'll have to wait. Why is that a factor? Because those windshields take a beating, much more than your typical car windshield. I have set a new record on my truck: I've now gone almost 16 months without replacing a windshield. Usually I go through 2 a year, at about $300 apiece. The current one has a repaired rock star on it, but other than that, it's holding up. Of course, some of that is a function of mileage, too.

mrblanche
09-07-2007, 10:56 AM
In the early '70s, Cadillac offered a 511 cubic inch (as I recall, might have the displacement off by a few ccs) 8.2 liter V-8 in its biggest boats - which weighed around 5,000 pounds fully loaded.

Today's biggest SUVs have V-8s in the 6 liter range and weigh around 6,000 pounds or so.

I'm just peeing in the breeze here, because I know little about RVs, but it seems to me that todrag around something that weighs twice or more as much, you'd want an engine with extremely high torque that was very, very tough.

While those big V-8s do make some decent torque - my guess is no more than 450-500 lbs.-ft. of it - and at fairly high RPM.

A diesel would give you much more torque 600-700 lbs.-ft (maybe more) at just off idle. It would also be a fundamentally stronger engine (super HD block/bottom end especially).

If it were me, I'd go diesel - for the durability and the power (torque).



Cadillac had a 472 and 500 ci engine. Actually, the same engine, two different displacements (different years) and real torque monsters. We have a few T club members with those engines, but they're more curiosities than they are practical engines. There is at least one company that specializes in hotrodding them.

If you want an engine that you can leave sitting for a year, then crank it up and drive it away, you probably want a gas engine. And the big 8-litre truck engines are perfectly capable engines.

DonTom
09-07-2007, 11:17 AM
"A short chassis is cheaper than a long one. "

How do you tell where the chassis ends? I am not sure what you mean by "overhang". Is that the area behind the rear axle or what?

-Don-

mrblanche
09-08-2007, 03:24 AM
Many class A chassis are actually truck chassis with no body. I see them trasnported quite often.

And yes, the overhang is the body behind the rear axle.

DonTom
09-09-2007, 09:38 AM
Many class A chassis are actually truck chassis with no body. I see them trasnported quite often.

And yes, the overhang is the body behind the rear axle.


The Sightseer model shown probably wasn't the 26 footer. The sightseer comes in many Lengths. Hopefully, the shorter lengths have a lot less overhang.

I am glad you mentioned it, as it's something I would not have thought of but a long overhang would probably make it more difficult (or not possible) to get the RV out from the side of the house. I cannot drive straight out because of trees, big rocks and all that type of landscaping junk in the way that's required by the HOA.

-Don-

mrblanche
09-09-2007, 10:07 AM
Come to think of it, you may be right. You'll find that often a number of lengths (say, 22 feet to 28 feet) are all on the same wheelbase, with the difference being the overhang. This is because it's easier to spec just a few wheelbases when they order the chassis, rather than a separate one for each length.

So, I guess the ideal would be to find the longest wheelbase on the shortest body length.

Mase
09-15-2007, 10:44 PM
It will be 26 feet regardless, as that's the smallest Class A RV made.

As for the overhang, why is it cheaper to build that way?

Our next RV might be the 26 foot model of the SightSeer, but won't be new. Perhaps at least five years old, but won't buy for at least a year as it would not get used until then anyway.

Here's what it looks like:

http://www.winnebagoind.com/products/winnebago/sightseer/ (http://www.winnebagoind.com/products/winnebago/sightseer/)

-Don-
]

NICE!

Much better than any hotel room along the way. As they say, getting there is half the fun......