LD1
Epic Contributor
In traction situations, no the added HP isnt really noticed. But when using the PTO, or when pulling in higher gears, it is noticed.
Does HP matter?
- Thread starter MARKMILES77
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Super Member
This fact does not escape me. I am questioning the degree of difference . Surely if one is cutting grass with a 5 hp mower and then goes to a 9 hp mower, differences will be noticeable as one is almost doubling their hp. I am wondering if at higher hp's in the range of these JD twins, how much of an advantage in practical terms exists. Certainly if one is able to jump to a 6' mower as opposed to a 5 footer on the lesser hp tractor then that percentage of width of cut would be applied to time saved. As I have never experienced this differential, it would be helpful to get a bit of a handle for those people buying a tractor for pasture or extensive grass cutting where the difference of a 38 hp tractor as opposed to a 50 or 60 hp tractor is rather obvious. My question is when dealing with these amounts of hp, (from 32 to 38) how many additional hp's are needed to really see a difference with rpm oriented attachments. Numerically at the motor there is an 8% difference. I do not think or I should say i do not know this necessarily equates that your work can go 8% faster unless your implement is also that much larger. There is also the added torque that may allow the tractor to go faster in higher grass but again, to what degree? There is a pervasive opinion for some that buying the larger hp motor is always an advantage and when in doubt, buy the larger motor. It is probable that JD is hoping for the same reasoning and attempting to compete with a particular market share. I am questioning this and trying to be more data driven.
SPYDERLK
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Not specific to JD, but our experience is quite definite in comparing the 2 Kub Ls. Driving the same 5' bushog the 3450 is much better. This advantage comes in its relative ease in accomodating the natuaral variance in the work. If all work was done on the flat it would be much less noticeable but if youve no, or little reserve the hills slow you down and make the job less enjoyable.
larry
LD1
Epic Contributor
38/32=1.1875.....Isnt that an 18.75% difference???
I do understand what you are saying, and really cant say if I know, because I only had enough money to buy one tractor at the time. Otherwise I could have bought a 2800 and a 3400 and test the theory.
But lets compair my L3400 (29HP PTO) to a L2800 (24HP PTO). My L3400 is 20% more power at the PTO. (and since the RPM is fixed, that also means more torque)
IIRC, with a gear transmission, my 4th gear (4H) is 4.3mph and 5th (1H) is 5.1 MPH. So my 5th gear is 18% faster.
Now I dont know, cause I dont own both tractors, but I would like to think that the extra HP would allow me to mow in 5th gear as well as the L2800 can mow in 4th. If the L2800 is mowing in 5th, and hits a patch of thick stuff and has to downshift, maybe the L3400 wouldnt??? I dont know. But 18-20% more power is never a bad thing IMO
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Super Member
Good comparison anyway Spyder. your 2550 shows 23 pto hp while your 3450 is at 30. This showing a difference of a bit less than 8% and you are still noticing it . Good practical applied info. Thanks
LD1
Epic Contributor
I sent you a PM arrow...
But 23 vs 30.....
The 3450 is 30% bigger than the 2550
The 2550 is 24% smaller than the 3450
The 2550 has 76% of the power the 3450 has
The 3450 has 130% of the power the 2550 has
Confused yet??
Marveltone
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This is why I hate calculating percentages. Hmm... Which way to go? Which sounds more impressive? Why don't the percentages stay constant? ARRRGGH!!! :banghead::hissyfit:
ullinghair:Joe
LD1
Epic Contributor
This is why I hate calculating percentages. Hmm... Which way to go? Which sounds more impressive? Why don't the percentages stay constant? ARRRGGH!!! :banghead::hissyfit:
Joe
Just the way it is. And it is used alot in marketing too:mur:
Which sounds more impressive (or less impressive) depending on what you are trying to do.
The 3038 has 30% more power certainly sounds better if you are wanting the 3038
BUT.....
The 3032 is only 24% less power sounds better if you are trying to justify not buying the 3038
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Super Member
Yes. thank you. I was interested in correcting it myself and would have. Allow me to do it anyway. The 3450 has 30 pto hp and the 25 has 23. 23 is 76% of 30. Wait a minute…that leaves 24%. How can it be 24% smaller and the 3450 be 30% larger?
LD1
Epic Contributor
Thats percentages for you.:confused2:
Think about EXACTALLY how you are saying it.
23 is 76% of 30. That means that the 23 is 24% smaller than the 30. so you are using 30 as your BASE number. IE: 7hp difference between the two. So 7hp smaller than 30hp is 7/30........which is 24%
30 is 130% of 23. That means that the 30 is 30% larger than the 23. In this case you are using 23 as the BASE number. So...7/23=30%
Its all in what you are comparing. When I am saying that the 23 is 24% smaller than 30, the number 30 is what you are comparing the HP difference to.
When I am saying that the 30 is 30% larger than the 23, the number 23 is what you are comparing the HP difference to.
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Let my try a different prespective and see if this helps. Lets forget HP and tractors all together.
Lets say someone weighs 200 lbs and wants to go on a diet. They loose 50lbs. That is 25%. They now weigh 150lbs.
With me so far.....
Now that 150lb person gains that 50lbs back. They just increased their weight by 33%, since the 50lbs they added is 1/3 more than they weighed.
Did that help?? Clear as mud right:laughing: