3.3 Litre Perkins in a series 3

[Miniman]

Well it looks like Jim Willy has come up with the better Idea for me. I was going to put the 2.5TD engine into the series 3 88" but Jim Willy said it would probably be better to put that in the 109" safari and the 3.3L in the series 88". Thinking about it the perkins are very good at breaking gearboxes and halfshafts so what is a more powerfull engine going to do like a 2.5TD......Humm Not just that the 88" is going to be for the playdays and the 109" is going to be for the road. Well the perkins only rev to 2500rpm so it would be a bit slow for the road in a 109" The 109" is going to be my everyday car and the series for greenlanes and off roading and we all know that we dont need speed for that. So what yall think.

88" 3.3 Litre Perkins
109 Safari 2.5TD

Lets hear your comments....

[dave_2A_2.25Turbo]

I would think you're as likely (if not more so) to break things with the Perkins - it's Torque that does the damage as opposed to BHP.  

You'll need Range Rover Diffs to use the Perky on the road successfully - to counteract the low rev range - and probably for the off-road toy as well (to make it bearable between the slow bits!)

My vote would be Perky for the 109 and 2.5TD for the 88

[Jim-Willy]

Oh come on.  Ya can't have a relitavely modern and quiet engine for screwing to death offroad and spend all your road driving week in a long wheelbase nail running a loud slow forklift engine.  It'd be lunacy :roll: .

[Miniman]

So figures just so people know.

2.5TD 90 BHP Which stands for Break Halfshaft Power

Perkins 4203 3.3 Litre 60bhp  45kw at 2600rpm 143 lbf ft

[Rich_P]

Just remember that the 2.5TD is still within the limits of the transmission, as it is similar in output to the 2.6 Straight-6 cylinder petrol engine.

[bezzabsa]

and that 2600 is about the max revs for a perkins, believe me if you think a 2.25 diesel is slow, wait till you try a perkins!!
my m8 USED to have one in his range...lasted about 3 weeks before he went back to the V8 and gas con'd it!!
how does 45 flat out sound?? and thats on a good day.

[bezzabsa]

if your worried about snapping half shafts, remember the V8 boys that use series stuff - its tougher than you think

[Miniman]

What you may not know is that I have 3.54.1 diffs in the series so yes it would have done 45mph but now it will be a little faster. Anyway the perkins is going to be for off roading anyway. NO NEED FOR SPEED....lol

[Xtremeteam]

a TD most definelty aint gonna blow diffs or shafts or anything like that

[Miniman]

So why would a 3.3L 60 BHP perkins do so then.

[bezzabsa]

So why would a 3.3L 60 BHP perkins do so then.

torque, pure and simple

[Xtremeteam]

So why would a 3.3L 60 BHP perkins do so then.

torque, pure and simple

yep

BHP sells cars,Torque wins race's,

[Miniman]

But the perkins has less tourque than the TD.... or are we going to say because the tourque is lower down in the rev range....?

[bezzabsa]

Right sorry about this, but this is a complete explanation. shamelessly 'borrowed'
Torque, Power, and Kinematics

The following discussion of basic physical principles involved in kinematics and dynamics of automobiles may bore some of you. It may also enlighten you. The discussion will be in no way satisfactory for those that study such physical phenomena on professional level or are true enthusiasts seeking advanced understanding. Rather it will be light and informative by just slightly touching the mathematics and physics involved. However, after reading the text and looking at the diagrams I hope that you will walk away with just a bit more understanding of the concept of power and torque.

In the consumer world of car salespeople, car magazines, internet groups dedicated to the wonder on four wheels, the words power and torque are heard a lot and used a lot. Ironically, very few people, according to my observation, know the precise definition and application of each terms as related to cars. What is better to have – more power or more torque? Are they related? Such questions puzzle many, but only few stray from pseudo-scientific explanations and myths. I will not try to answer these questions directly; rather I will give definitions and relations, letting you find the answers for yourself.

Let us begin:

In our universe we’re given three independent quantities: length, time, and mass. All other quantities are derived from the three main ones.
Let us label them as:


L – length
T – time
M – mass

Then speed, for example, is s = L/T. Force is f = (M *L) / (T * T). Note that these quantities are independent from our system of measurement. Speed can be measured in Miles per Hour or Parsecs per Millennium.


Let us now define what torque and power are as a function of the three fundamental quantities:

Power is the rate at which one does work or work per time.
Work is a force applied over a distance or force times distance.
Thus power is: p = (M * L * L) / (T * T * T).

Torque is force applied at a moment arm of a given length.

Thus torque is: t = (M * L * L) / (T * T ).

Comparing the above two formulas, one can clearly see that the only difference between the two is that power has one more time factor in the denominator. One is wise to notice this because if there is a quantity that has a formula 1 / T and that is physically relevant, we can multiply it by torque to get power.
Such quantity does exist and in our case, due to the geometry of force application, it is the rotational speed of the engine’s crankshaft or more simply, the engine speed.
Thus in our case:

Power = C *torque * engine speed.

What is that C doing there? That C is a factor that has to do with the measurement system that we’re using. If you happen to measure torque in ft-lb, engine speed in revolutions per minute (RPM), and power in SAE horsepower, C comes out to about 1/5250. If you happen to measure torque in meter-newtons, engine speed in radians per second, and power in Watts, C = 1.

Let us stick to our SAE motorheads measurement table. Then we have a formula relating torque and power:

Power = Torque * RPM / 5250

Great. Assuming it’s right, so what?

Well, consider we want to accelerate a car with mass m from 0 to speed s using an engine with constant power p. How much time will it take?
Well, the car will undergo an kinetic energy change of: k = (0.5 * m * s*s) – 0, or the difference between the kinetic energy of the car at rest and at speed s.
Now this kinetic energy change was brought about by work done by the engine. Since we know that power is work per time, we know that by dividing total work done by the applied power, produces the time needed to do the work and thus time to accelerate the car.
So what does this tell us? This tells us that it is the power that accelerates the car.

But what about torque?

Remember that:

Power = Torque * RPM / 5250.

Examine the formula carefully….
It says that power has two variable components – torque and engine speed. Naturally, the torque here is the "twisting force" developed at a particular engine speed. So there is more than just torque involved into accelerating the car. After all, you can apply torque all you want, but if the engine is not spinning, there is no work done, no power produced and you're not moving anywhere.
Another interesting feature is that at 5250 RPM the numeric magnitudes of torque and power figure will always match in our measurement system, irrespective of the number of cylinders, volume, valve train or any other such feature of the engine. Cool, huh? This is a very fundamental notion because it tells us that power ALWAYS grows faster with increase in RPMs than torque does. We’ll see how that is used in engine building later.

Now that we’re armed with this new understanding, let us examine a few idealized examples.
Consider an engine which develops exactly same torque T throughout its allowed RPM range. In this case torque is constant and:

Power = RPM * T/5250 which is a straight line with a slope T/5250 (see graph below).
How does this car behave? Smooth and predictable. The power increases linearly and the higher RPMs you attain, the more power you develop all the way up to the redline. This is the ideal curve for an engine – maximum torque everywhere in the range leaves only the RPM as the limiting factor. See graph below.








The next example is where torque is a linear function of the RPM.

Torque = a * RPM + b where a is the slope and b is the base torque developed when the engine is barely moving.
From our trusty power/torque formula we deduce that in this case:

Power = (a * RPM * RPM + b *RPM) / 5250.

Not hard to see that power is a quadratic function of the RPM. Notice that power rises much faster, as a square of RPM, than in the first example. Thus high power and acceleration can be attained, but you need to spin the engine faster. Notice that power is always rising faster than torque. See graph below.




So, what is important? Well, as you can see, at low RPM, if you want to develop lots of power, then you simply need lots of torque at those engine speeds. That is why you hear – high low-end torque being a good thing. But, in order to develop high low-end torque you either need a large engine or forced induction scheme. So the makers of small engines have focused their attention on the other side of the spectrum – high RPM side taking the advantage of the fundamental law that allows power to outgrow torque provided torque doesn't diminish too fast with rise in engine speed. There, it’s the high RPMs that make horsepower even if the torque being developed is only marginal.
What does that mean? If you’ve got an Integra and want to accelerate fast, you better keep you tachometer needle way higher than a 5.0L Mustang GT next to ya! :-)

So the next time somebody asks you what’s important and what to look for, you’ll know what to say.

[Miniman]

So after reading that what it is , is because the perkins will only rev to 2600rpm that means the tourqu is stronger in a small amount where as the 2.5td say revs to 5000rpm the tourqu is applied over a longer length. It was all very confusing to me.......

[bezzabsa]

I posted it and it confused me!!!!
torque is pulling power, bhp is speed power
easy
i think??
if you are stuck in the mud and have 1000bhp wheels will spin
same situation with 1000 ft lbs torque = movement
bhp will provide momentum, torque will pull
hence why offroaders use torque, racers use bhp

I'm not helping am i???
 :shock:

[Miniman]

If you have a vehicle with 30bhp and 150lbs torque it will acelerate slowly and pull a big heavy trailer up a hill slowly.

If you have a vehicle with 130bhp and only 30lbs torque it will acelerate fast but not pull a big heavy trailer up the hill that easy.

That is how I understand it.

[H]

just stick rangie diffs and 1/2 shafts in the 3.9 v8 developes around 220 lb of torque and about 170 bhp if they can withstand that they can withstand your deisel better still put the 2.5 td in your road car and get a v8 for your play car ;)

H

[p4203]

hi chris
 i have used my 109 with a 3.3 for a year no probs every day for work and greenlaning did a hundred miles before christmas one outing kept up with the 90's and hybrids you just got to adapt your driving to suit you also might get better mpg out of the 3.3 over the 2.5
 good luck with your choice still think you need a rrc :D

[Miniman]

Morning guys you both up nice and early. Still got your book p4203 will get it back to you asap. H I cant stick rangie halfshafts in because they to long you are forgetting that its got standard series 3 axels so that is not possible. I wonder if we are going to get any snow to play in.... :)

[p4203]

no worries about the book know where you live  :D
 
 as for snow hope not today as i am working but i heard a rumour we might at last get some in the middle of the week :lol:

[Miniman]

There is snow on the hills at Skipton. The book came in handy last night as thats where I got the bhp from. Well it looks like I have no option but to put the engine and gearbox into mine now. Just got back from swimming with the kids and as I was on my way to barnoldswick the landy gave me a big bang.....Thought nothing of it as I thought may be I hit a brick in the road then not 10seconds after BANG again and no drive.... It had jumped out of HI box put it back in and set off again....Hummm Drive slowly I said to myself and NOTHING.... So its now in the catagory of [!Expletive Deleted!].... Looks like I going to be fitting the 4203 into the little 88"....Hummm bet thats a nice drive what ya think P4203.... And the rangie diffs

[p4203]

will be fun nice and bouncy heavy lump that perky if your stuck for a gearbox i have a s11 and a s11a you can have for free condition unknown but you should be able to make a good one up out of the 2
 if it helps
 mark

[Miniman]

Oh Mark you are a STAR....I will go for the gearboxs if you are happy with that.....Excelent....They supposed to be the best box for a series motor. I have alot of pints to buy you now mate. Hope ya come camping this year on one of mine and Jim Willys greenlane doos.... They are fun.....

[H]

well get rangie axles then then you can have your disc brakes and coil springs.... know what just get a rangie ;)

H

[p4203]

no worries chris
 small favour if you know anyone who wants a s11 swb to play with fairly cheap when we sort the boxes out see what you think of it as it's got to go to keep my s111 109

[Miniman]

YEP YA NOT WRONG....You cant get rid of the 109....4203... Or I will be lost in the world with the only perkie in the dales.... :( ....may even buy it myself..... JIM WILLY BE GOING "NOT ANOTHER......"

[Jim-Willy]

Chris :shock:

Take deep breaths and put your wallet away........... :P  :lol:

[Miniman]

But it will also be tax exempt........ please...... :roll: