Thread: 700Nm puma ???

Even if they printed the dyno figures, these sheets you see for 1000+hp skylines and the like. Check out the correction figures at the bottom of the page. They input the ambient and inlet temps to be extremely high (40+ deg) so the dyno up's the figures as if it was corrected to a "normal" ambient and inlet temp (usually set < 20deg). They dyno then spits out these ultra figures.

That's why I got poopooed on the last V8 I built. NA toyo 3uz 5.7 with "only" 800hp. So we re-ran it with higher dyno settings and everyone went wow when I said we used new injectors only and ran 1200+.

Mostly true ...usually torque and Hp cross at 5252rpm.... But my main doubt on this puma without considering fueling etc etc like John explained to create that much power in a diesel we all know it's in relation to the amount of fuel burnt and to burn the amount of fuel to get those figures i doubted that by simply changing the internals of the standard turbo would safely create enough boost to do this...I would start to believe the figures if there was twin turbo or more mods but then again I recon it's like polishing a turd in the end you've got a shiny turd

Well I've read through it and it says it has a replaced internals of the turbo, 2.5 inch exhaust, ported and polished head and a performance chip. It's claimed to get 138 kw and 689nm and it was also tuned on a dyno. I'm not to sure about it but I'm open to the idea.

Originally Posted by Series3 GT

Well I've read through it and it says it has a replaced internals of the turbo, 2.5 inch exhaust, ported and polished head and a performance chip. It's claimed to get 138 kw and 689nm and it was also tuned on a dyno. I'm not to sure about it but I'm open to the idea.

I still highly doubt it ....500nm is a lot of torque and this 689-700nm suposedly ... If it is truly that much I'd hate to think what I was getting out of my Isuzu intercooled 30psi fuel screw sitting in the centre console

Originally Posted by c.h.i.e.f

Mostly true ...usually torque and Hp cross at 5252rpm....

They only cross at 5252rpm if you measure power in hp and torque in ft-lbs. Working in metric the cross is something like 8,000rpm (I worked it out once a long time ago).

Originally Posted by Series3 GT

Well I've read through it and it says it has a replaced internals of the turbo, 2.5 inch exhaust, ported and polished head and a performance chip. It's claimed to get 138 kw and 689nm and it was also tuned on a dyno. I'm not to sure about it but I'm open to the idea.

700Nm on a 2.4 litre diesel would require around 60psi boost. (calculated, not guessed).
That is not possible with anything resembling the original turbo. You would need a set of compound turbos.
That's just the air-side, without being concerned about trivial matters like keeping the engine together on the inside.

In addition, the claimed 700Nm even at 2000rpm produces more than 138kw. Put simply, none of the claims add up.

This claim fits neatly beside the 1000Nm Toyota 4.2 (changed air-filter and exhaust) and the Nissan SR20DET which was claime to be 700Nm but wasn't breaking a gearbox rated at 250Nm.
Most people don't understand torque.

Originally Posted by Dougal

They only cross at 5252rpm if you measure power in hp and torque in ft-lbs. Working in metric the cross is something like 8,000rpm (I worked it out once a long time ago).



700Nm on a 2.4 litre diesel would require around 60psi boost. (calculated, not guessed).
That is not possible with anything resembling the original turbo. You would need a set of compound turbos.
That's just the air-side, without being concerned about trivial matters like keeping the engine together on the inside.

In addition, the claimed 700Nm even at 2000rpm produces more than 138kw. Put simply, none of the claims add up.

This claim fits neatly beside the 1000Nm Toyota 4.2 (changed air-filter and exhaust) and the Nissan SR20DET which was claime to be 700Nm but wasn't breaking a gearbox rated at 250Nm.
Most people don't understand torque.

Auh thanks dougal I'll check my books and see if there was a mistake with the graph about the first statement I feel there may be a typo according to your study...interesting though...

Also cheers for explaining the situation like that as that's exactly what I was getting at its not possible...

Lol about the Toyota comment

And

As for the gearbox my puma at factory spec 360Nm the gearbox is something that worries me (noises) see how it holds up I suppose

Was looking back at some previous work. We took a fairly stock (cams/exhaust) toyo 20v with fixed inputs and made it run 800hp next to a built 14000rpm monster 20v which with running ambient sensors ran <700.

But the torque figures were, while not accurate, were in order of higher figures for the better engine (and higher than actual). So it does put figures out and up as I earlier mentioned but as opposed to hp torque stays relevantly related.

Originally Posted by c.h.i.e.f

Auh thanks dougal I'll check my books and see if there was a mistake with the graph about the first statement I feel there may be a typo according to your study...interesting though...

...

No typo in whatever reference you took the crossing rpm from. Dougal didn't dispute that, he was making the point that where the torque and power curves cross is a consequence of the units of measure used and not to read anything else into the coincident.

I see some still think that 700Nm might be believable/achievable. My earlier post pointed out that If the power was as stated, then the torque was in error, or if torque was as stated them power was in error. Perhaps those people couldn't see that connection for some reason!

Engine dynos, measure torque over a range of rpm, then calculate power from those values. Chassis dynos do much the same, but the problem is the reduction in the gearing increases the torque (measured at the tyre tread), and there are losses between the engine and tyres. When the measured/calculated values are referred back to the engine, the results are open to error.

A diesel engine produces a torque vs rpm curve that has a shape that will somewhat follow the shape of a curve of volumetric efficiency vs rpm of the engine, i.e. the peak torque very nearly occurring where VE is greatest and falling at high rpm as VE drops. Power still increases as torque drops while rpm increases.

When performance of diesels is increased, the torque curve is similar just moved up. So if the torque was increased to 700Nm, it should still be at nearly the same rpm, and the shape should be similar. Then for 700Nm torque the power would have to be much greater than quoted, unless the torque dropped dramatically (unrealistic) from the rpm where it peaked.