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It's sooo flat and wide


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#1 Canuck

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Posted 13 August 2013 - 13:59

I stumbled across this dyno image the other day while looking for information. I was amazed by the relative flatness of the torque over such an enormous spread. How does one design such a steady BMEP across such a wide range of operating speeds?

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#2 Magoo

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Posted 13 August 2013 - 14:28

Doesn't matter, torque is irrelevant. Corny mathematical artifact.

#3 kikiturbo2

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Posted 13 August 2013 - 16:24

Saw the same thing with the gsxr 1000 engine I am using in my build.. That one uses twin sets of inlet throttle bodies and a valve in the exhaust to get a "nice" even spread of torque. Not being a bike rider myself I can only presume that they actualy want a nice even spread of torque for driveability..

#4 MatsNorway

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Posted 13 August 2013 - 17:32

Saw the same thing with the gsxr 1000 engine I am using in my build.. That one uses twin sets of inlet throttle bodies and a valve in the exhaust to get a "nice" even spread of torque. Not being a bike rider myself I can only presume that they actualy want a nice even spread of torque for driveability..


Say you run too much compression to get max power on high rpm.. Would not such a thing prevent knock on peak VE?

You tune it to close a bit during the most efficient rpm areas.

#5 kikiturbo2

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Posted 13 August 2013 - 20:26

Say you run too much compression to get max power on high rpm.. Would not such a thing prevent knock on peak VE?

You tune it to close a bit during the most efficient rpm areas.



sounds like an interesting idea..

#6 MatsNorway

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Posted 13 August 2013 - 20:49

sounds like an interesting idea..


Really?

Edited by MatsNorway, 13 August 2013 - 20:52.


#7 Dipster

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Posted 14 August 2013 - 05:52

Doesn't matter, torque is irrelevant. Corny mathematical artifact.



Mr Magoo! I am not sure that is quite right.

Tell that to the millions of industrial diesel engine users in the world. And the owners of the old US monster V8s with 2 speed auto boxes.

#8 gruntguru

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Posted 14 August 2013 - 07:00

Don't start him. His post was tongue in cheek.

#9 kikiturbo2

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Posted 14 August 2013 - 09:32

Really?


actually, I am pretty darn sure it is being done allready with variable valve timing..

Hell, I had to play with variable intake timing recently on an evo that had a cam change... couldn't get rid of knock without it (at same boost level).

valves in the exhaust system have been a part of 2 stroke tech for a while, and was used on a lot of 4 strokes, especially on bikes. Logic would tell me that on cars variable valve timing is a better way of doing it. In any case, both have to do with changing the VE of an engine, and, as you pointed out, you can use it to play with high CR and try to solve some of related knock problems...


#10 Lee Nicolle

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Posted 14 August 2013 - 10:35

Torque is king, HP is for the bullshit in the pub. The dyno engines for dyno shows prove that. Monster numbers that mean very little.

#11 Canuck

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Posted 14 August 2013 - 12:37

Wait wait wait. That is decidely not what I wanted to get at. Rather want to avoid it.

#12 mariner

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Posted 14 August 2013 - 12:49

Motor Cycle News quotes a higher max torque

http://www.motorcycl.../R-NXGN-3083888

no idea which is right!

#13 Canuck

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Posted 14 August 2013 - 12:55

Factory does as well but the factory clearly states it as at the crank. I think they rated it at 50.