3 cyl vs 4 cyl?

[Joshua Rod]

Is there much of a difference when working a 4cyl as opposed to a 3 cyl? I have a super c that I do loader work with, and I have a field cultivator that I till up our pastures up with (really sandy loose soil so it handles an 8 ft really well). All the newer equip has 3 cyl which I am sure is better for fuel economy and emissions, but if you had the same hp and the same conditions pulling the same plow, etc do the smaller motors have the same smooth "pull" that more cylinders have?

Maybe this is all personal preference...
 

[Michael Price]

I have a IH 484 with a 3cyl diesel and it runs as smooth as a electric motor. I had a case DB 995 and it was a 4cyl diesel buy 2 cyl would fire at the same time. The IH when one piston is TDC one is midway and the other is BDC.
 

[Janicholson]

Threes have less inherent vibration, and a bit less friction, but they are not dramatically superior.
Putting higher RPM on a 3 gives it the same pulses per minute that a 4 has. They are fine. If modern in the sense that they have electronic fuel injection (diesel or gas) and electronic ignition and engine management, those are superior in performance for those reasons alone. Jim
 

[Joshua Rod]

Do they typically run at a higher rpm?
 

[David G]

I would use the appropriate number of cylinders for the HP requirement. The newer engines will be 2,3,4,or 6 cylinders, the older ones were 2,4 or 6.
 

[Janicholson]

Typically the newer the tractor the higher the rpm. It is free displacement in the sense that it pumps more air, and makes resulting power. The wear factor is not important, it is usually not twice the RPM. Jim
 

[gene bender]

Your SC will out pull any of those new hi-tech 3cycl all day long.
 

[Brad Motheral]

What do you base that on Gene?
 

[dhermesc]

How "modern" are your 3 cylinders? The engines made the last 10-15 years can hardly be compared to engines designed 75 years ago and built 60 years ago. Air flow, fuel injection, electronic ignition have all improved. Compare a Chevy 235 I6 (3.9 Liter) to a "new" Chevy 2.2 engine. Almost half the size with much more HP and torque and they both run on 87 octane.
 

[DGK]

My take on 3cyl vs 4cyl is you can have the same horse power but A 12 horse lawn tractor will not pull what a 12 horse farm tractor will. And these new compacks have to have 4 wheel drive to come close to pulling a disk or plow. The larger rear tire makes alot of difference. Just my 2 cents. Doug
 

[MisterT]

[dhermesc]

I don't recall the 235 being much on durability. The babbitt bearings should be enough said on that topic.
 

[Owen Aaland]

[wolfman]

No the 3-cyl engines are usually not as smooth & quiet as the 4-cyl. of the same size and hp.
 

[John G. Hasler]

> A 12 horse lawn tractor will not pull what a 12
> horse farm tractor will.

No, of course not, for two reasons:

a) Horsepower is speed times force and determines how fast a machine can pull whatever it is that it can pull at all. "Pull" (i.e., draft) is a measure of the maximum force the machine can exert and is limited primarily by what it weighs.

b) Farm tractor horsepower is what the machine actually delivers to the wheels. Lawn tractor horsepower is the most that the manufacturer was ever able get out of the engine on a test stand in the lab.

> The larger rear tire makes alot of difference.

Tire size matters, as does tread, but weight dominates.