Torque vs Energy. Same units, not the same thing

[sosic2121]

What I dont understand then is the choice of language. You say that you sacrifice peak power for a low end torque gain. No wonder people get tricked!
You are saying that you are sacrificing 7hp at the peak rpm which is rarely used to gain 10hp at rev ranges that are used more often. Of course it is an improvement, you are increasing the power most of the time.
Why talk of power / torque? Why not choose a torque/torque or power/power wording?
It is like saying that Bolt made his frist 50 meters at 36 km/h but then changed to 10m/s for the final spurt.

I think there are 2 reasons.
1. tourqe curve gives us better picture what is happening with the engine and how efficiently it's running.
2. In the last 20 years (since TDs become so popular) I have never seen fair comparison between petrol and diesel.
Tourqe is overhyped and power is ignored. why?
400Nm at 1500rpm sounds much better then 63hp

[rjsa]

The torque vs energy metric units thread becabe the old "what's better, torque or horsepower" argument.

Time to lock, IMO.

[jz11]

Sorry to bang on, but I'm trying to simplify this to explain it accurately, with as much brevity as possible, without being incorrect.

42

that is about as simple and accurate as it can get.

[Jolle]

If, after 11 pages of simple explanations, graphics and calculations, it's still nog clear, it's time to re-do highschool. People, this is really basic physics.

[strad]

Dear God
Please lock this one too.
Same old same old

[godlameroso]

Between 4,500 to ~7,900 there's an across the board improvement 15-20ft lbs of tq, but there's a 7hp deficit at 8,400 rpm. Compared to the same car with another "tune" and different mods, granted we're talking about 167 ft lbs vs 148 ft lbs peak difference, and on average about 15 ft lbs over 3,000 rpm. I don't know what that equates to power wise probably 10 hp average increase everywhere in that range but a little bit less peak.

Sounds like really big midrange gain and small top end loss.

When you shift up revs are going to drop from 8500 to around 6500rpm.
At those revs(6.5k) power difference will be up to 20hp.
So, I think your "weaker" engine will be faster, especially in lower gears.

The crazy part is this was all done with playing with the cam timing, and afterwards tuning ignition and fuel on an otherwise stock engine. Honda's are pretty cool like that, for NA engines anyway.

[sosic2121]

Between 4,500 to ~7,900 there's an across the board improvement 15-20ft lbs of tq, but there's a 7hp deficit at 8,400 rpm. Compared to the same car with another "tune" and different mods, granted we're talking about 167 ft lbs vs 148 ft lbs peak difference, and on average about 15 ft lbs over 3,000 rpm. I don't know what that equates to power wise probably 10 hp average increase everywhere in that range but a little bit less peak.

Sounds like really big midrange gain and small top end loss.

When you shift up revs are going to drop from 8500 to around 6500rpm.
At those revs(6.5k) power difference will be up to 20hp.
So, I think your "weaker" engine will be faster, especially in lower gears.

The crazy part is this was all done with playing with the cam timing, and afterwards tuning ignition and fuel on an otherwise stock engine. Honda's are pretty cool like that, for NA engines anyway.

I thought it might be s2000 or civic type r engine
I've heard before that cam advance(4°) transformed the stock engine, big midrange gain for slight top end loss.
It's interesting to see that Honda left so much performance on the table, especially when you consider vtec...

[godlameroso]

It does, it's a huge improvement on track, it evens out at high speeds.

[Jersey Tom]

The topic of conversation has changed a bit, but I don't think it's necessarily lock-worthy.

My 2 cents on it - when talking about large scale differences in engines, comparing a 200 peak hp vs. 100 peak hp. engine will give you a pretty good idea of performance difference. You at least have a shot at drawing some reasonable conclusions at a glance.

200 ft-lbf peak torque vs. 100 ft-lbf peak torque really gives you no clue. Tells you nothing.

When you're getting into more subtle differences like different tunes, headers and intakes, etc. on one type of engine - yes, this is where the more secondary things come into play. Could be what you're limited on with gear and transmission options by rule. Could be the type of racetrack and particular ambient conditions for the day of which one will be better. You can't just eyeball two dyno curves with say single digit torque/power trade-offs and immediately conclude which one is better.

[gruntguru]

Tests done by some auto magazine comparing acceleration times of various makes and models.

[jz11]

was the article called - "guide in abusing math and statistical analysis, or how to make nice looking charts that mean nothing"?

[sosic2121]

was the article called - "guide in abusing math and statistical analysis, or how to make nice looking charts that mean nothing"?

It clearly shows connection between bhp/ton ratio and (low speed) acceleration. One can easily conclude that power to weight ratio, while not the only factor, it is the most important the for acceleration!
It also shows there is no direct connection between lbft/ton and acceleration.

[jz11]

was the article called - "guide in abusing math and statistical analysis, or how to make nice looking charts that mean nothing"?

It clearly shows connection between bhp/ton ratio and (low speed) acceleration. One can easily conclude that power to weight ratio, while not the only factor, it is the most important the for acceleration!
It also shows there is no direct connection between lbft/ton and acceleration.

right, and you concluded that without knowing gear ratios the cars were ran in?

there is so much data missing from those charts that I will not even begin to comment on that, useless pretty high level board meeting type of stuff - easy to "understand" and essentially totally pointless

[rjsa]

The topic of conversation has changed a bit, but I don't think it's necessarily lock-worthy.

was the article called - "guide in abusing math and statistical analysis, or how to make nice looking charts that mean nothing"?

Off top trolling. Time to rethink it?

[rscsr]

The topic of conversation has changed a bit, but I don't think it's necessarily lock-worthy.

was the article called - "guide in abusing math and statistical analysis, or how to make nice looking charts that mean nothing"?

Off top trolling. Time to rethink it?

Although he sounded kinda rude, I agree with him. These are just nice pictures with a whole lot of variations. I mean you can get the same acceleration with 125-180 bhp/t and if you squint a bit you can see a slight trend to higher accelerations with higher torque, although with also a lot of variations.
I mean it pretty obvious to me that torque has not much to do with acceleration but this is still kinda bad science.