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-   -   Pancake / Pusher (http://www.skoolie.net/forums/f39/pancake-pusher-13969.html)

Stu & Filo. T 05-25-2016 11:22 AM

Pancake / Pusher
 
Does anyone know the difference between a Cummins 855 Pancake configuration & 855 Pusher? it's my understanding the difference is Oil pan & oil pump pickup.
Is there more to it & what would be involved in converting one to be used in a Crown Pusher?
:confused::confused::confused::confused::confused: :confused::confused:

Stu & Filo. T 05-25-2016 01:54 PM

Quote:

Originally Posted by Stu & Filo. T (Post 149868)
Does anyone know the difference between a Cummins 855 Pancake configuration & 855 Pusher? it's my understanding the difference is Oil pan & oil pump pickup.
Is there more to it & what would be involved in converting one to be used in a Crown Pusher?
:confused::confused::confused::confused::confused: :confused::confused:

What I'm getting at is I might have the opportunity to score a 14L Cummins, right now I have a 8.3 Cummins rated at 250hp in my Crown RE, would this motor work in it's place & will it bolt up to my Allison 647 Trans??

Robin97396 05-25-2016 03:58 PM

Our minds think alike, although I probably have much less retention.

That was my theory. Bigger engine so it didn't have to work so hard. I can't answer the technical questions, but when I purposed a similar upgrade from my 5.9 to a 8.3 there wasn't much enthusiasm. The end result seems to consistently be that it costs more to do these modifications than it does to get a bus with the right engine and transmission already in it.
That being said, you're not going to find a 14L in a bus to my knowledge. That's a pretty uber engine.
I'm questioning why your 8.3 only has 250 hp. My 5.9 has about 195 or something like that. It seems your power could be bumped up considerably and more economically without the engine swap. I'm pretty sure you know how expensive radiators are for trucks, and that 14L is going to need a bigger one than your 8.3 uses. At the same time I can see your argument because the 14L won't be working hard and may not need extra cooling until you're in a pass or pulling a heavy load. That's some serious hp.

Stu & Filo. T 05-25-2016 04:46 PM

Quote:

Originally Posted by Robin97396 (Post 149935)
Our minds think alike, although I probably have much less retention.

That was my theory. Bigger engine so it didn't have to work so hard. I can't answer the technical questions, but when I purposed a similar upgrade from my 5.9 to a 8.3 there wasn't much enthusiasm. The end result seems to consistently be that it costs more to do these modifications than it does to get a bus with the right engine and transmission already in it.
That being said, you're not going to find a 14L in a bus to my knowledge. That's a pretty uber engine.
I'm questioning why your 8.3 only has 250 hp. My 5.9 has about 195 or something like that. It seems your power could be bumped up considerably and more economically without the engine swap. I'm pretty sure you know how expensive radiators are for trucks, and that 14L is going to need a bigger one than your 8.3 uses. At the same time I can see your argument because the 14L won't be working hard and may not need extra cooling until you're in a pass or pulling a heavy load. That's some serious hp.

The School district I bought from is in the middle of the California Desert with a hill not in site so they didn't need a lot of power. I buddy of mine knows quite a bit about the Cummins tells me I could punch out the 8.3 to 500 hp but then you start dealing with reliability, it would be nice to Cruz 70 mph all day long without over stressing a motor. I'm also told the 14L weighs about 1500 lbs over, about a foot longer, a foot higher & about a foot wider then 8.3 but that's all I've been able to find out so far.

crazycal 05-25-2016 06:07 PM

Quote:

Originally Posted by Stu & Filo. T (Post 149920)
What I'm getting at is I might have the opportunity to score a 14L Cummins, right now I have a 8.3 Cummins rated at 250hp in my Crown RE, would this motor work in it's place & will it bolt up to my Allison 647 Trans??


I think you would need to figure out a couple of thinks first. First, how to not blow up your transmission. Also, I think that engine uses a SAE #1 housing.

cowlitzcoach 05-25-2016 08:19 PM

The 855 Cummins in a mid-ship installation is totally different from an 8.3L in an RE installation.

You would not be able to use an 855 with an MT647. The 855 has too much HP and torque for the MT series of transmissions. You would need to upgrade to an HT series.

Two other big issues would come up in trying to install an 855 in an RE.

First is the length. Not only is the engine longer but an HT is longer than an MT transmission. I don't think you would be able to shorten the driveshaft 24" which require extending the frame and building a doghouse on the rear bumper to accommodate the longer length of the power package.

Second is heat. Increasing the HP by 50% is going to require a substantial increase in the cooling capacity. In a Crown or Gillig with a mid-mount engine, the cooling system is designed to accommodate an engine with upwards of 450 HP. In a Crown or Gillig with an RE, unless it came from the factory with a 6V-92 pushing 350 HP, the cooling system isn't large enough to push much past 300 HP without experiencing problems. In fact, in my experience, most Gillig RE buses have problems on hot days on long grades with everything working correctly.

I am not saying it can't be done. I have seen pictures of a Kenworth Pacific that a guy swapped in a Cummins L10. It required the addition of a dog house on the rear bumper that stuck out almost three feet from the back of the bus. I always wondered if he didn't have problems with curb cuts scraping with that much sticking out that far behind the rear bumper.

opus 05-25-2016 09:12 PM

Quote:

Originally Posted by Stu & Filo. T (Post 149941)
it would be nice to Cruz 70 mph all day long without over stressing a motor.

Why dont you look at gearing instead of an engine swap?

Robin97396 05-25-2016 09:46 PM

I am absolutely uninformed about crowns. So would that 14l fit in there? I've never even seen the engine compartment on one of those, although I do remember riding in some of the earlier ones. The bus, not the engine compartment. Sorry nostalgia, I was looking for something more modern. An aerodynamic brick shape actually.

I don't know how much spare room you've got, if any. Usually there isn't the kind of additional dimensions like you've been talking about in an average engine compartment. It sounds powerful and loud. Sounds like that one needs to come with it's own transmission too.
You seem to be trying to make a very powerful bus. Cool.

Stu & Filo. T 05-25-2016 11:47 PM

I would like more power & better drivability, the 855 was a thought because I could practically steal it but didn't know about feasibility of mounting to trans & getting it in the spot. If it would require different trans & cost thousands & thousands to convert then I guess I'll stick with the 8.3

Stu & Filo. T 05-25-2016 11:50 PM

Quote:

Originally Posted by opus (Post 149984)
Why dont you look at gearing instead of an engine swap?

gears & ability to maintain speed would still require horsepower


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