And you thought Gruppe-S' dyno was a heart breaker...
08-05-2007, 08:28 PM
#1
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And you thought Gruppe-S' dyno was a heart breaker...
Just to give a baseline, my car's last tune was from Vishnu on their dyno dynamics, and was pulling 240 awhp. A few mods have changed since then, such as a Crucial PnPnC manifold and a TurboXS TMIC.
This is the result of my tune today. Baseline was over 30 hp under Vishnu's
Power Mods include: VF-35, TurboXS V1 TMIC, PDE Catless UP, MRT Turboback w/ catted DP, Group-N Engine Mounts, Crucial Port & Polish & Coated exhaust manifold, ECUTek, Prodrive 3 port boost solenoid. + Support mods of fuel pump, injectors, etc.
Oh yeah, to give you guys another perspective, the guy who owns the dyno said stock STis put out around 200-210awhp on this dyno.
This is the result of my tune today. Baseline was over 30 hp under Vishnu's
Power Mods include: VF-35, TurboXS V1 TMIC, PDE Catless UP, MRT Turboback w/ catted DP, Group-N Engine Mounts, Crucial Port & Polish & Coated exhaust manifold, ECUTek, Prodrive 3 port boost solenoid. + Support mods of fuel pump, injectors, etc.
Oh yeah, to give you guys another perspective, the guy who owns the dyno said stock STis put out around 200-210awhp on this dyno.
Last edited by STi-owns-evo; 08-06-2007 at 01:05 AM. Reason: list of mods
08-06-2007, 09:36 AM
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I know the fan thats used can dramatically effect how much power a car will make on any given dyno, but I'm not really sure as to why one would read lower given the same circumstances.
08-06-2007, 10:18 AM
#6
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well for one thing, he dyno'd you in 3rd, which is not the ideal 1:1 ratio. If he dyno'd you in fourth it would put you up about another 10% and probably be comparable to what you would see on the Mustang 
08-06-2007, 10:28 AM
#7
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I asked him about that, and he said with the way this dyno was set up it limits speed to 200kph, so if your car tries to go any faster it'll put load on it to not allow the car to go any faster. (not sure why it does that, maybe as a safety feature?) Also, he said when he talked to the manufacturer of the dyno, they said it doesn't really matter what gear you use since the final drive gear will always change the gear ratio anyway.
08-06-2007, 11:10 AM
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thats nonsense, even if the rear end ratio was 1:1, the torque multiplication difference from your 3rd gear to 4th gear is nearly 30%, the dyno rollers cant tell what gear your in, just how much energy is turning the rollers. Ask any tuner of any dyno what happens when you dyno a car back to back in different gears
08-06-2007, 11:22 AM
#12
thats nonsense, even if the rear end ratio was 1:1, the torque multiplication difference from your 3rd gear to 4th gear is nearly 30%, the dyno rollers cant tell what gear your in, just how much energy is turning the rollers. Ask any tuner of any dyno what happens when you dyno a car back to back 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.
08-06-2007, 11:26 AM
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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.
