12 replies to this topic

[Canuck]

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?

[Magoo]

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

[kikiturbo2]

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..

[MatsNorway]

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.

[kikiturbo2]

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..

[MatsNorway]

sounds like an interesting idea..

Really?

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

[Dipster]

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.

[gruntguru]

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

[kikiturbo2]

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...

[Lee Nicolle]

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.

[Canuck]

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

[mariner]

Motor Cycle News quotes a higher max torque

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

no idea which is right!

[Canuck]

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