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Dyno Graph Question - What do you make of this?


boo5td6
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Hi Guys,

Sorry for the crappy photos... I know its hard to see however these are the only ones of the old dyno pic  I could get, you can make out whats going on though. Its been a lonngg time.

I am in the process of getting ready for a tune... need to get all the new bits etc together and work out what sort of tune I want. 

This was the tune that was done on it before. Keen to get ppls thoughts on how this car would perform and if these are ideal curves to make the car as quick and easy to manage in corners as I can for the power. I see so many ways to skin a cat when I look at different dyno sheets and how the cars make power its left be confused after tonnes of reading. What you can see is a very very flat power curve right through which I never see, most seem to be in more of an arc up to max power. The torque curve as you can see ramps up hard and drops off.

This looks very different to most dyno graphs I have seen where power slowly increases to redline rather than getting to full power and staying flat right though 2/3 of the rev range. Would this sort of graph show you that it makes for a quicker more predictable car through corners and fast down the 1/4 seeing as it gets to peak power so fast or is there a better way? 

Sorry for all the questions, so much stuff out there i am trying to work out how I should ask to get it tuned. 

 

Thanks a mil :)

 

Screen Shot 2018-01-15 at 12.18.29 AM.png

Screen Shot 2018-01-15 at 12.22.29 AM.png

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Assuming that the charts are not backwardly labelled or some other issue, then the power is flat because the torque curve is falling off.  The engine is not making torque after 125 on the speed scale.  If the problem is not in the tune (which would have to be timing) then it must be flow limited.

The nasty wiggle in the AFR at 125 should be ironed out, but that's not a huge issue.

In short, this is not a normal setup.

 

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Ideally the torque curve comes up to the "peak" value as early as possible and stays there, flat, until the redline.  This is not usually completely achievable.  On turbo engines especially, you don't get anywhere near peak torque until you have all the boost.  And at the top end, as any air flow restrictions (ie turbine housing) start to take effect, torque will drop off.

A completely flat torque curve gives you a linearly rising power curve.

Turbo engines usually have a rather more savage arrival of both torque and power at the point where the boost arrives, meaning that the power curve is often very low and flat, followed by very steep, followed by a more linear section once boost is stable, followed by a drop off if the torque curve suffers as mentioned above.

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