And you thought Gruppe-S' dyno was a heart breaker...
08-06-2007, 12:40 PM
#22
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Actually the dyno HAS to know about the resulting ratio. This happens one of two ways... either the dyno operator performs a calibration to match wheel speed and RPM, or the dyno software calculates the ratio using RPM data from the inductive pickup and comparing it with wheel speed. Either way, the dyno software has to know about the relationship between wheel speed and RPM to properly calculate torque and whp. If it doesn't know this ratio, the numbers and shape of the curve will be way off with anything other than a perfect 1:1 resulting ratio.
So assuming the dyno operator properly calibrates this ratio, the only variances in measured power when using different gears would come from boost variances due to varying loads and potentially the slightly varying drivetrain loses experienced in different gears.
So assuming the dyno operator properly calibrates this ratio, the only variances in measured power when using different gears would come from boost variances due to varying loads and potentially the slightly varying drivetrain loses experienced in different gears.
though that only raises another issue since the dyno graphs rpm/mph readings are way off, looks like the dyno thinks its running a wrx in FIFTH gear!?! (150mph at 7200rpm)
08-06-2007, 12:55 PM
#23
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Car Info: 05' Evo MR w/E85 - 10' Ralliart Sportback w/E85
93mph
Another thing to note is it's using SAE correction which will change the actual real numbers. The GST mustang does no correction. It is what it is at the time you dyno as last I checked we don't drive our cars in a bubble. It also looks like the dyno operator used two different SAE corrections for before and after. I see fish in the sea.
Last edited by earlyapex; 08-06-2007 at 12:58 PM.
08-06-2007, 01:59 PM
#27
Good eye.... that does seem a bit shady. Although it looks like the correction for the baseline is actually higher than the correction for the tuned results. I'm not sure how the correction number actually works on this particular dyno, so that observation doesn't necessarily mean much. Either way, it seems odd to use two different corrections unless the conditions in the dyno facility changed drastically between pulls.
as much horsepower as you want.
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