Engine swap fuel efficiency?

[cranetruck]

Question for you guys, who have made the engine switch from the multifuel to a more conventional engine; was there a change in fuel economy?
How many MPG's before and after the swap, that's the question.

The multifuel engine uses a combustion process, which is more controlled than the conventional, supposedly producing less knock under low load conditions, an overall improved efficiency (more complete combustion) and less sensitive to the kind of fuel burned.

Thanks,

 

[cranetruck]

Nobody wants to step up here?
Still curious,

 

[red devils dude]

the members that have them aren't around much.

 

[M35guy]

Spicergear did one I think. his I believe is a Cat diesel and something like a 7 or 8 spd tranny.

 

[red devils dude]

Spicergear has a CAT 3408(I think) and the stock spicer 3053A.

 

[Westech]

heck my multi gets 10-12 mpg all day when taking it ez. i love that thing just wish i had a little higher gear to keep the revs down to 2200 or so. other then that its a good motor and I cn beat the crap out of it and it still has never left me anywhere. if you were to do a swap you might want to stick with a motor around the same size. any more and its too much power to keed the mpg's up and too small your going to have to work it to deth to make the thing move (and lose mpg's) its a small fit if thats what your looking for. remember that todays tractors around deuce/5 ton size only get aroung 5-8 mpg. the multi is really not that bad if you look at it.

 

[cranetruck]

Here is a description of the combustion process (image below):

 

[Boatcarpenter]

This link describes Spherical(hypercycle) chamber and 3 other types.
http://64.78.42.182/sweethaven/MechTech/Automotive01/default.asp?unNum=4&lesNum=1&modNum=2

 

[Boatcarpenter]

Finally found the link to a picture.
http://www.sweethaven02.com/Automotive01/fig0505.gif

 

[cranetruck]

The last figure is right out of the 1985 TM 9-8000 manual, figure 5-5, page 5-6.

 

[cbvet]

Westech, you get 10-12 mpg? I get 5 on the highway, pushing 50 mph. I thought mine was normal.
Eric

 

[cranetruck]

I go along with Westech's numbers, I get 9-10 mpg on a long trip including ilde times. I drive at about 55 plus for hours on end.
My gross vehicle weight is about 18,000 to 20,000 lb (most recent Florida trip).
5 mpg for a deuce on the highway is not anywhere near normal, perhaps for 5-tonner...

 

[Westech]

check your air filter!! that thing has to be clean clean clean!! Im instaling a 5 ton fender filter and that should bring up the mpg's even more. 5 mpg is a tad low for a multi. even the gov says a deuce should get 8.5 mpg on road.

 

[cbvet]

Okay, so what's wrong?
I've mentioned before that this thing blows a LOT of smoke, & I asked if the fuel could be turned down to reduce it.
Most of the responses said to add a turbo. I don't want to.
Wouldn't some sort of fuel adjustment help?
I starts great in cold weather. Runs really well. Really don't need the manifold heater.
Any other suggestions?
Eric

 

[Westech]

you can turn it down if you want, but the thing to do is run E-85 or reg 89 gas diesel mix. 25% gas works really well to cut the smoke.

 

[Djfreema]

A turbo will increase your mpg. At least it did after I turbo charged a N/A 1986 v.w. jetta. Bumped up the mpg by about 4-5mpg, not to mention the added power.
That was without increasing the fuel rate.

 

[cranetruck]

Eric, how are you measuring the fuel consumption?

 

[Katch1]

cranetruck if you are looking at an engine swap, and want good milage, I think you would need a 5.9 cummings, I've seen someone advertises swapping this motor into deuces. I don't know how they would perform for your application. I had one and liked it, never scaled much over 17,000 with that truck, but it performed ok. i also saw that somebody put the 7.3 ford in a mud truck they had made, I do have a 7.3 in my current truck, and have scaled beyond 20,000 many times with no ill effects in 3 1/2 yrs, m.p.g are only in the low teens at this weight, where I never got the cummings under 15

 

[cranetruck]

Katch1, don't get me wrong, I have no reason to want to swap engines. Just interested
in comparing MPG's with a different engine in the deuce (not other vehicle).

 

[cbvet]

I checked mpg using the odometer & fuel used. I made no allowance for idling time, but I can't imagine it would add much.
As I've mentioned previously, the smoke is so bad, that the high school band stayed back nearly 1/4 mile at our last parade.
It doesn't use oil.
So what about "turning the fuel down" to improve mpg & reduce smoke? How is it done? How do I make sure I don't get it too
lean & damage the engine?
And thanks guys, for the helpful suggestions!
Eric