Cowabunga
Member
- Location
- Ceredigion,Wales
I'd hazard the opinion that a tier3 6470 [four cylinder] would easily outperform a tier2 6480 and be equal to a Perkins engine in a tier3 6480
High horse power four cylinders can’t sustainably do the same job as a larger six pot of similar HP. Tell me I’m wrong
- Thread starter Hazza6930
- Start date
Lakesdigger
Member
Not an ideal comparison mind two tractors 5 years apart one possibly at the end of its production run and another possibly at the start of its run could be meeting vastly different emissions standards.
- Location
- Ashbourne, Derbyshire
Both are Tier 3 (6470 is Sisu, 6480 is Perkins)
Cowabunga
Member
- Location
- Ceredigion,Wales
There you go!
No, it wasn't a guess and neither did I know for sure what you have. Just my experience with the models' respective performance.
Why increasing wear on brakes and transmission because of a 4cyl? Possibly are you implying less engine breaking or more shifting of gears?
- Location
- Northumberlandia
Sisu 4pot sounds poor compared to its 6yl cousin more so on tickover,
pulling at 1500revs there aint much in it.
Id still have a 6 all day long tho
9" overall length longer between a T3 6480 & current 6718S
4 cylinders are typically smaller overall in comparison to six cylinders so there for wear must be increased/concentrated on a smaller machine? I don’t know if it would be a considerable about mind you and a lot would depend on the operator in my opinion
Cowabunga
Member
- Location
- Ceredigion,Wales
They are not. The only difference generally is a slightly shorter wheelbase. Transmissions and everything are built to take the power and torque whether four or six cylinders. Wear is not increased in the slightest. A turbo is a turbo is a turbo and will, or should if treated with respect, last at least 10,000 hours and more with a bit of luck. Let it build up oil pressure and warm before revving and cool and idle before shutting down. Change the oil and filter regularly and make sure the air cleaner is regularly cleaned and changed now and again. This last one is often neglected and causes a thrust load on the turbo bearings which is sure to shorten its life. The turbo has no idea what size of engine it is fitted to. It is a piece of inorganic engineered metal. What's the difference in its life whether it is attached to a large and powerful four cylinder or a larger and far more powerful six cylinder. I'll give you a clue. Nothing.
suffeks
Member
everyone assumes 6cyl same hp makes more power... sure I guess probably higher displacement so it will make more torque
but if you tell me the 4 cyl vs 6 cyl has the same hp and same torque then what is the difference? nothing
I know people that still tell me a turbo 200hp car is more powerful than a non turbo 200hp car. lol what? 200hp is 200hp. but usually the turbo cars have more torque so they are faster. same thing here 6cyl probably more torque.
but if you tell me the 4 cyl vs 6 cyl has the same hp and same torque then what is the difference? nothing
I know people that still tell me a turbo 200hp car is more powerful than a non turbo 200hp car. lol what? 200hp is 200hp. but usually the turbo cars have more torque so they are faster. same thing here 6cyl probably more torque.
There’s no replacement for displacement
Cowabunga
Member
- Location
- Ceredigion,Wales
Absolute rubbish. A soundbite that is as much a cliche as the old ‘oil is cheap insurance’ when used by Americans to justify unnecessary 3000 mile oil changes in 1980’s and younger cars.
I can absolutely guarantee you that a modern three cylinder 90hp will run rings around a MF390 and even a turbocharged MF 5445 tII which is also rated at 90hp.
You're wrong. The four pot will be cheaper to run, cheaper to fix and cheaper to service. On top of all this, the machine will probably last just as long as a big 6, as long as it's maintained properly.
This is not unlike the argument years ago about "rubbish" utes/pickups/trucks being fitted with tiny turbocharged CRDI engines instead of the smokey gutless boat anchors fitted in the "good old days". Or when the old boys would go on about their old carbed V8's of the 70's, "that was real power back then boy, you wouldn't know what real power is nowadays". Then they crush the beer can on their forehead, throw it over their shoulder and open another one.
There's no replacement for displacement? Yeah right. Technology replaced displacement years ago.
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- Location
- Mid Norfolk
Turbo engines will have a flatter torque curve and achieve maximum torque at lower rpms.
As for displacement vs. forced induction, fag packet maths will tell you that 1bar of boost will effectively "double" the displacement of an engine as you are doubling the the mass of air and fuel capable of being burnt on each cycle. This is rarely practically achievable due poor breathing, mechanical inefficiency and thermodynamics, especially in tractors, but there are plenty of 2.0 petrol turbo car engines producing 250+bhp reliably when a NA 4.0 V8 is barely managing 50bhp more.
The internal components on a turbo engine are obviously under more strain, but these days the engineering is well understood and widespread so there should be little difference on longevity.
@Hazza6930 What tractors are you running at the moment?
We owned MF6480 and a 5480 at the same time and found that they were very evenly matched doing the same type of work, and cost of servicing was very similar.
We owned MF6480 and a 5480 at the same time and found that they were very evenly matched doing the same type of work, and cost of servicing was very similar.
Pistonbroke
Member
Surely the only fair comparison would be a four and a six that are the same displacement? Both ,for example, five litre engines.
Exfarmer
Member
- Location
- Bury St Edmunds
I used to be a firm believer that capacity equals performance and only a V8 was a real engine.
Then I once had the pleasure of driving a US engined Ford Mondeo in New Zealand
The hire company were apologetic when I picked it up they only had the big car left in stock.
We are in for a treat I said to the wife, a real car for a change
It was the biggest heap of S**** I had driven for years , my wife's little BMW diesel hatch would have left it standing
Then I once had the pleasure of driving a US engined Ford Mondeo in New Zealand
The hire company were apologetic when I picked it up they only had the big car left in stock.
We are in for a treat I said to the wife, a real car for a change
It was the biggest heap of S**** I had driven for years , my wife's little BMW diesel hatch would have left it standing
GeorgeK
Member
- Location
- Leicestershire
Come the zombie apocalypse I know what engine I'd choose and it wouldn't be small capacity highly tuned turbo super charged with variable cams and valves and whatnot. When they're after your brains I wouldn't be confident mowing down zombies with anything but a 5.9 cummins or a cast iron 2v pushrod v8
I dont doubt the capability or even reliability of the 4 pots, but in my experience a 6 of the same size is slightly easier on diesel than a big 4, as well as smoother. Granted this may vary tractor to tractor, but big 4 pots overall are not measurably better on diesel than the equivalent 6. the price difference nowadays between equally specced 4 and 6 pots is pretty much negligible, so whats the point in buying the 4?
Courier
Member
- Location
- M62 - M1 - M18 triangle
Displacement is about making room for more air (For oxygen to burn the hydrocarbons) - Or you can force a similar amount of oxygen into a smaller cylinder using a Turbocharger with or without an intercooler.... Been going on in mainstream UK farming since 0971 when Ford brought out the 7000.
Tractor Barn Productions - The Story Of The Ford 7000
Tractor Barn Productions Tractor and Farm Machinery DVDs made for enthusiasts by enthusiasts
www.tractorbarnproductions.com