Author Topic: Is this what I want  (Read 3118 times)

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Offline wobblywalrus

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Is this what I want
« on: August 17, 2017, 12:24:54 AM »
The power curve is from a dyno at elevation 150 feet.  It is a NA motor running on gasoline.  Note how the curve is climbing when it hits the rev limiter.  We lose peak power at B'ville.  Does the rpm at which peak power is produced lower?  If so this might be the curve I want. 

Offline Sumner

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Re: Is this what I want
« Reply #1 on: August 17, 2017, 12:33:58 PM »
Just a couple thoughts without knowing much about your setup.  What is your rpm drop between shifts, especially the last one or two?

You are making more HP above 7200 with the new power curve but less under it.  If you drop much lower than 7200 on those last shifts then you might not have the power you need to climb back up where you are now making more power.  If your rpm drop doesn't go below 7200 then I think your new found power will be quite noticable  :-D.

If you haven't figured out your rpm drop between shifts one of these spreadsheets will give you the info you need for shifting at any point...

http://purplesagetradingpost.com/sumner/bvillecar/bville-spreadsheet-index.html

... go down the menu to the one that fits your application,

Sumner

Offline RansomT

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Re: Is this what I want
« Reply #2 on: August 17, 2017, 08:50:20 PM »
I would assume it works just like what I see on the dyno.  As the barometric pressure drops, the entire curve makes less power.  The shape of the curve including the peak TQ/HP remains the same, just a lower reading.

Offline wobblywalrus

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Re: Is this what I want
« Reply #3 on: August 20, 2017, 10:02:51 AM »
That is what I assume, too.  It would be nice to verify if it actually does this or if there are other changes to the torque and power curves we do not know about.  A power and torque curve set from a NA engine dynoed near sea level and at SLC might be exactly what I need to look at.