Engine swap for GM

[TomC]

Chaz- keep in mind that you can run a 4 stroke with your V730 by adding a reverser gear to it.  The simplest would be to locate a Cummins L10 that would be a bit more power than your 8V-71, but with the Cummins engine turbo would feel like alot more.  And don't worry about the gearing-you probably won't wear it out even if you ran it at 2300rpm all day long.  Course, the 4.1 rear end ratio would be perfect.  Good Luck, TomC

[Chaz]

Thanx Tom and Skip!

That motor doesn't look all that big. But I guess it could just be the pic. Is 210 HP enough for my 4108?

Does the 8.3 or L10 need any sort of adapter to bolt up to the trany? 

Wait a minute guys............................................................. Time for me to take a breath.  I'm getting waaaaaay ahead of myself here. Sorry. I better get my motor checked out before I get myself all worked up in a lather over this. I definitely LOVE the info and learning about all this, but I should probably slow down a bit. (just like in my driving!  )

So for now, or untill someone posts what they swapped and how they swapped it, an 8.3 or L10 are good motors to use. (?) That's really all i should be thinking about at this point. But I will be reading up on any of this kind of thing if others post it, or if there is somewhere else to go.

And as I mentioned earlier, IF I should do a swap at some point, it would be -shall we say- for the "long haul". Mileage is also a good consideration and power comes in third.

Thanx guys. This is good info and I apppreciate it.
     Chaz

[skipn]

Chaz
    We all hope that it is something minor $ for your current engine to be healthy again

   From my opinion.................anything <270 hp is a dog. A friend of mine has a 8.3 in his S&S class A.
   Stock 210 was a real bad bed wetting dog! He put a bigger turbo on and he is much happier. He couldn't
   afford the full HP kit for his engine but he is saving his money

   L10 for straight mechanical then there are L10E and M11 for the electric type controls. As with any of these
  the electronic versions are a lot easier to bump up HP.

    FWiW
    Skip

[Chaz]

Skip,
  So when considering a motor, go for 280HP or over. (?) Cool. Got it.
  I like power as much as the next Hot Rodder but, I don't want or need to have it at the sacrifice of "decent" fuel mileage or motor longevity. (I can hardly believe I just wrote that!! Man, this getting close to 50 yrs. old is hard on a young feller! )

I'd also like to keep it mechanical. HOPEFULLY for the ease of working on it and parts. But also so I am not tempted to "turn it up". (MAN..............I better go take my tempature and lay down for awhile. I just wrote another one of those funny sounding sentences!!  )

But like I said earlier, I better slow down a little bit. I want to do what is right for the long haul and that is usually taking it a little slower. But I would LOVE to see/hear what others have done. I do still thrive on that.

Hope I didn't hijack your post to bad John!!    Sorry!

Thanx Skip.
   Chaz

p.s. I did see and drive a '48 Flxible with a 6V71 in it and it was like a Hot Rod! Then up at the Auburn Car Auction I seen two other Flxibles about that same year. One had a 454 Bow Tie motor in it and the other had another 6V71. The guy with the Bow Tie said he got 10mpg at 70 mph no problem. And it looked B-E-A-U-T-I-F-U-L in there!!

[Dallas]

Hope I didn't hijack your post to bad John!!    Sorry!

Thanx Skip.
   Chaz

p.s. I did see and drive a '48 Flxible with a 6V71 in it and it was like a Hot Rod! Then up at the Auburn Car Auction I seen two other Flxibles about that same year. One had a 454 Bow Tie motor in it and the other had another 6V71. The guy with the Bow Tie said he got 10mpg at 70 mph no problem. And it looked B-E-A-U-T-I-F-U-L in there!!

And the Fish in the pond are longer, the Check's in the mail, and "Honey I will Respect you in the morning"

It's a rough job to get 10MPG out of a 454 in a Chevelle, let alone a 20,000 Lb bus.

Dallas

[TomC]

Chaz- there are many a bus with the Cummins L10 mechanical running through the reverser gear utilizing the V730.  You'll get about 335hp and 950lb/ft torque, with the L10 weighing about 300lb less than the 8V-71N.  Worth looking into.  Easier to cool too!.  Good Luck, TomC

[Don4107]

Tom, is the reverse gear for a V730 and add in or is it a different trans?

Thanks
Don 4107

[Charles Seaton]

Dallas,

The early Flxible transits were T-Drives.  The later versions of thier new look were V-Drives, nearly identical to the GM New Looks.

[Dallas]

Dallas,

The early Flxible transits were T-Drives.  The later versions of thier new look were V-Drives, nearly identical to the GM New Looks.

Yup,

They were, however, the basic monocoque construction still applies. If you look at the bones of one you won't see a lot of difference between the V-Drive and the T-Drive. Yes the rear may have been extended farther, or the drive axle may have been set closer to the steering axle, but you still have the same basic coach. In the later ones, even the parts are interchangeable.

Now, If you look at a PD4104 or one like mine, a PD4103 and compare it to a new look GMC or a New Look Flx, You still have the same basic structure. There's no rocket surgery here... what is the difference in adding 15- 160 lb passengers in the back end or removing those same passengers, plus their seats and adding a T-drive and some conversion stuff.

Too many people without any experience and/or any personal knowledge of how a monocoque system works like to parrot what others have told them.

C-47's (DC3's) are of a monocoque construction, plus have heavy wing loads, however, many of them were upgraded in engines and armament.. Not sure you remember, but the famous "Puff" as used in Vietnam was a C-47 armed with a a set of quad 50mm Brownings and a 90mm recoilless rifle. These were placed in the rear of the plane, behind the exit door.
With just the recoil from the 90mm, according to popular bus nut myth, the tail should have fallen off the plane after the first shot.

The B-25 had a 105 Howitzer mounted in the nose... sorry, might have been the B-26. Either way, those were both monocoque construction built for a completely different purpose, load and stress factor.

My point here is, NEVER NEVER NEVER underestimate the ability of a monocoque construction to handle the load placed on it.

Dallas

[JohnEd]

Chaz,

You did NOT highjack my thread.  This thing went straight where I hoped it would go,,,,info for you and others.  And ME....I am in the mix here.

Somebody smart here suggested that I only consider buying a complete truck with the engine I want.  For my purposes that would include the trans but it may make sense for you also.  Lotsa parts on a truck you might find useful and the scrap prices are outa sight for the remainder.  Sell the diff and trans and rad online.  Food for thought?

About your engine:  Remove the air box cover plates from the side of the engine.  Wrench over the engine and look at each piston.  Take a good pic of each.  Post the pics on here and get opinions of the condition.  If they are badly scored you will need at least an in-frame and will know that you need look "no further".  If they are good send the injectors (that you have already removed) off to be evaluated.  If they come back good do a compression check through the injector hole.  Good pistons...good injectors...good compression equals a REAL mystery.  The last i heard, three years ago, the injectors were selling for $70 each but are sold in a set of 6 or 8.  I am not the man on this though and look at my comments as my starting a thread.

I am pleased that i could benefit you in this way.

John the Happy

[tekebird]

Dallas,

the aircraft examples you gave are really like comparing apples to oranges.

both were thought out by engineers not done in the field by mechanics. and were fairly overbuilt aircraft.

also both recoil forces from the big guns have someplace to go rather than into the structure alone.

both of your aircraft examples had aircraft movement due to the recoil forces.

Yes it is true anything can be done.  The problem comes in doing the structure modification to accomidate a major change like this..  I kow of several 4104's that had structure failure  at the rear of the coach due to heavy tounge weight loadings

I also know of several still tooling around that are subject to similar loadings.

the problem is that the bus was designed to haul the 15 passengers above the floor not below it.

When one starts to do major changes you change alot of force vectors etc.

Again not that it can't be done but.

1. I would want some structural engineer to do some vector analysis

2. cost and time  in a project like this usually far outweigh the benefits.

Unless you are in love with your bus and you have some crazy desire to take on a huge engineering/fabrication project that could end up a failure, I'd pass and buy a different bus.

[tekebird]

to hit on another Aviation example.

Most of the recent Air Taker ( firefighting aircraft) accidents were wing failures.

which were contributed to wing loadings that the struture was not designed fo.

Two of these aricraft.  a PB4Y  (navy B24) and a C-130 I knew the crews.

[Dallas]

Dallas,

the aircraft examples you gave are really like comparing apples to oranges.

both were thought out by engineers not done in the field by mechanics. and were fairly overbuilt aircraft.

also both recoil forces from the big guns have someplace to go rather than into the structure alone.

both of your aircraft examples had aircraft movement due to the recoil forces.

Yes it is true anything can be done.  The problem comes in doing the structure modification to accomidate a major change like this..  I kow of several 4104's that had structure failure  at the rear of the coach due to heavy tounge weight loadings

I also know of several still tooling around that are subject to similar loadings.

the problem is that the bus was designed to haul the 15 passengers above the floor not below it.

When one starts to do major changes you change alot of force vectors etc.

Again not that it can't be done but.

1. I would want some structural engineer to do some vector analysis

2. cost and time  in a project like this usually far outweigh the benefits.

Unless you are in love with your bus and you have some crazy desire to take on a huge engineering/fabrication project that could end up a failure, I'd pass and buy a different bus.

Doug, Although you are correct that the Mitchell was re-engineered at great taxpayer expense, the cannon as mounted was in the nose of the aircraft making it a really good target for antiaircraft fire... you had to point the plane at the target and hold it there in order to fire. Pilots reported that when the gun fired the recoil would jar them so badly it felt as is the plane stopped in mid flight for a split second.
The C-47 "Puffs" were actually not engineered in a factory or on a designers table. They were the product of expediency to interdict truck traffic on the Ho Che Minh  trail. The 90 mm recoilless was stuck out the side door to begin with and only later was it mounted on a pod built just for the purpose. The DC3/C47 Platform was so well engineered it could take the side stress of multiple firing without any problems.. also remember, some of those same planes were built during and before WWII, (many are still flying in other parts of the world).

As for wanting an engineer to always design something, umm, I just refer back to the first space shuttle disaster... caused by an improperly designed O-ring seal. Or the Titanic disaster where the water tight bulkheads didn't extend to the top deck, or even the WWII Liberty ships that had a tendency to break in half because of poor engineering practices.

[tekebird]

well anyone can point fingers....with just about everything being designed by an engineer now days.  ( save the new Eagle) obviously there wil be some failures.

the Shuttle accident was the failure of an O ring....however the engineers new it had passed out of it's operating temp range......the accident was the fault of beauracracy and business not by engineers outside of them  not making a bigger no go stink.

Titanic.......would have sunk even with full enclosed compartments.  would have floated a bit longer but still would have sunk.  that accident was really an operator error accident

Yep, someone can do anything they want if they throw enough time and money at it.  smart or logical is another question.

20 years ago in a dirt bike magazine an author made the comment " you can make a coffee table win a National Motorcross title if you throw enough money at it"

it comes down to

Do you have the time?

Do you have the money?
Do you have the know how?

[TomC]

The reverser gear for the V730 is an add on.  Good Luck, TomC