Rennlist Top 10 HP/TQ
#333
Three Wheelin'
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haha no that was the run that was shut down from overboosting (24 psi on pump gas)
why I don't really count it
https://rennlist.com/forums/showthre...&highlight=355
I could have sworn the mustang was the one that read higher, damn!
why I don't really count it
https://rennlist.com/forums/showthre...&highlight=355
I could have sworn the mustang was the one that read higher, damn!
#338
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Oh I didnt know you referring to posting it on the list... dude you made the power, one way or another, you deserve to be on the list! let me know if you change your mind
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#339
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maybe the vitesse stg 3 will get me up there! heh
good to know:
A Mustang Dyno is one of the BEST tuning devices you could ever use. They put a wideband oxygen sensor down by the collector of the header, so you get VERY accurate readings instead of delayed readings and readings when the exhaust has cooled down by the time it hits the tail pipe, which is where some Dynojet operators put it. A Mustang Dyno requires that you enter a weight for the vehicle and then provides a resistance throughout the entire run, simulating wind resistance. For this reason, it is an excellent tuning device but its no good to put down big numbers. Once a car begins moving, there is less resistance at the wheels when you overcome the polar moment of inertia, but the Mustang Dyno keeps applying this force acting against you. If you were on a Dynojet you would only have to overcome the polar moment of inertia and then you'd have nothing but BIG numbers getting put down. The Dynojet will generally put down another 10-15% more whp than a Mustang Dyno.
The Dynojet is actually an accelerometer whereby it uses a 3000-3200 pound drum that is used to create an inertia load on the vehicle being tested. The vehicle's horsepower (HP) and torque try to overcome the weight/inertia of the drum to accelerate it. As a result the software and electronics try to measure the horsepower and torque that the vehicle is developing to overcome the drum's weight and inertia. The resulting horsepower and torque will be higher than a true loading dyno because once the drum starts rolling not as much power is needed to keep it going.
good to know:
A Mustang Dyno is one of the BEST tuning devices you could ever use. They put a wideband oxygen sensor down by the collector of the header, so you get VERY accurate readings instead of delayed readings and readings when the exhaust has cooled down by the time it hits the tail pipe, which is where some Dynojet operators put it. A Mustang Dyno requires that you enter a weight for the vehicle and then provides a resistance throughout the entire run, simulating wind resistance. For this reason, it is an excellent tuning device but its no good to put down big numbers. Once a car begins moving, there is less resistance at the wheels when you overcome the polar moment of inertia, but the Mustang Dyno keeps applying this force acting against you. If you were on a Dynojet you would only have to overcome the polar moment of inertia and then you'd have nothing but BIG numbers getting put down. The Dynojet will generally put down another 10-15% more whp than a Mustang Dyno.
The Dynojet is actually an accelerometer whereby it uses a 3000-3200 pound drum that is used to create an inertia load on the vehicle being tested. The vehicle's horsepower (HP) and torque try to overcome the weight/inertia of the drum to accelerate it. As a result the software and electronics try to measure the horsepower and torque that the vehicle is developing to overcome the drum's weight and inertia. The resulting horsepower and torque will be higher than a true loading dyno because once the drum starts rolling not as much power is needed to keep it going.
#340
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I'll have to try and find the second dyno sheet on the track car - 351/347. The sheet on the link is 337/327, then switched software(vitesse race chips), tweaked the fuel a bit and got 351/347 on the second go round.
#341
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Originally Posted by emwporsche
btw, which dyno reads low? mustang or dynojet?
#342
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Originally Posted by emwporsche
The Dynojet is actually an accelerometer whereby it uses a 3000-3200 pound drum that is used to create an inertia load on the vehicle being tested. The vehicle's horsepower (HP) and torque try to overcome the weight/inertia of the drum to accelerate it. As a result the software and electronics try to measure the horsepower and torque that the vehicle is developing to overcome the drum's weight and inertia. The resulting horsepower and torque will be higher than a true loading dyno because once the drum starts rolling not as much power is needed to keep it going.
If you are at a steady speed (not accelerating) then the only power needed to keep the drum rolling is the power to overcome frictional losses and rolling resistance of the tires. However, in a typical dyno run on the Dynojet, the drum does not run at a steady speed but is constantly being accelerated under WOT and it takes more and more power to get it moving to higher speeds. The power required does NOT decrease.
One reason the Dynojet usually gives higher numbers than the loading dynos like the Mustang is because of the proprietary "correction" factors used to compute torque and horsepower from acceleration (these are not the usual corrections for temperature and altitude). Nobody (except Dynojet) seems to know exactly what those factors are. What's the purpose of these corrections? For one thing, the car is not only accelerating the drum but also its own drivetrain and in particular the wheels, which have their own inertia totally independent of the drum. These external components add to the total inertia that the engine has to overcome to accelerate the drum. The Dynojet computation software allegedly applies a correction factor for drivetrain/wheel inertia, because otherwise the hp/torque numbers would actually be low! However, the Dynojet has no way of knowing what that external inertia is, so there is no way the correction factors can be right for any particular car except by dumb luck. That's why you can get better hp numbers by running lighter wheels on a Dynojet dyno (but not a Mustang). The bottom line seems to be these Dynojet correction factors are overly generous and result in inflated hp/torque numbers.