GT3's Dyno numbers
01-12-2012, 04:40 PM
#31
Nordschleife Master
Unless the numbers all come from the same dyno, you can't compare numbers from one dyno to another one. They all give you different results. I learned this when I dyno tested a car on 3 different dyno's and saw a spread of 20% in hp from lowest to highest.
Dyno's should be considered tuning tools that allow you to see changes when you stick with one dyno. But don't consider the numbers to be absolute truths.
Dyno's should be considered tuning tools that allow you to see changes when you stick with one dyno. But don't consider the numbers to be absolute truths.
I'll ask him to post
01-12-2012, 07:04 PM
#32
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none of this is worth a bag of donkey's doodahs. Grown ups take the engine out of the car and put it on an engine brake. That's it period - no discussion.
The chassis dyno has a function and that is to measure the incremental differences between different modifications to the engine/driveline in the same chassis.
As you are all aware, the elves at Zuffenhausen put every single engine on an engine brake and send back all engines which do not make enough power or make too much power. However, within the allowed output tolerances there is a noticeable difference.
For the dyno figures here, it would have been helpful to have the data for each vehicle before and after the mods were installed. Then you could have normalised the results for dyno and engine variations. Without that kind of information you are playing with the soap in the bath, metaphorically speaking.
R+C
The chassis dyno has a function and that is to measure the incremental differences between different modifications to the engine/driveline in the same chassis.
As you are all aware, the elves at Zuffenhausen put every single engine on an engine brake and send back all engines which do not make enough power or make too much power. However, within the allowed output tolerances there is a noticeable difference.
For the dyno figures here, it would have been helpful to have the data for each vehicle before and after the mods were installed. Then you could have normalised the results for dyno and engine variations. Without that kind of information you are playing with the soap in the bath, metaphorically speaking.
R+C
01-12-2012, 07:57 PM
#34
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none of this is worth a bag of donkey's doodahs. Grown ups take the engine out of the car and put it on an engine brake. That's it period - no discussion.
The chassis dyno has a function and that is to measure the incremental differences between different modifications to the engine/driveline in the same chassis.
As you are all aware, the elves at Zuffenhausen put every single engine on an engine brake and send back all engines which do not make enough power or make too much power. However, within the allowed output tolerances there is a noticeable difference.
For the dyno figures here, it would have been helpful to have the data for each vehicle before and after the mods were installed. Then you could have normalised the results for dyno and engine variations. Without that kind of information you are playing with the soap in the bath, metaphorically speaking.
R+C
The chassis dyno has a function and that is to measure the incremental differences between different modifications to the engine/driveline in the same chassis.
As you are all aware, the elves at Zuffenhausen put every single engine on an engine brake and send back all engines which do not make enough power or make too much power. However, within the allowed output tolerances there is a noticeable difference.
For the dyno figures here, it would have been helpful to have the data for each vehicle before and after the mods were installed. Then you could have normalised the results for dyno and engine variations. Without that kind of information you are playing with the soap in the bath, metaphorically speaking.
R+C
01-12-2012, 08:14 PM
#36
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none of this is worth a bag of donkey's doodahs. Grown ups take the engine out of the car and put it on an engine brake. That's it period - no discussion.
The chassis dyno has a function and that is to measure the incremental differences between different modifications to the engine/driveline in the same chassis.
As you are all aware, the elves at Zuffenhausen put every single engine on an engine brake and send back all engines which do not make enough power or make too much power. However, within the allowed output tolerances there is a noticeable difference.
For the dyno figures here, it would have been helpful to have the data for each vehicle before and after the mods were installed. Then you could have normalised the results for dyno and engine variations. Without that kind of information you are playing with the soap in the bath, metaphorically speaking.
R+C
The chassis dyno has a function and that is to measure the incremental differences between different modifications to the engine/driveline in the same chassis.
As you are all aware, the elves at Zuffenhausen put every single engine on an engine brake and send back all engines which do not make enough power or make too much power. However, within the allowed output tolerances there is a noticeable difference.
For the dyno figures here, it would have been helpful to have the data for each vehicle before and after the mods were installed. Then you could have normalised the results for dyno and engine variations. Without that kind of information you are playing with the soap in the bath, metaphorically speaking.
R+C
01-12-2012, 08:21 PM
#37
Racer
Sorry but I disagree with a lot of the assumptions about chassis dynos here. I have tested and analyzed hundreds of 911s through thousands of runs on virtually every dyno out there (Dynojet, Mustang, Dynapack, Dyno Dynamics, Superflow, Maha, Land-Sea and others I don't remember) and the only one I see deliver consistent numbers are Dynojets. You can dyno a car on a Dynojet in Los Angeles and get the same wheel hp numbers on another Dynojet in New York within 5 hp, usually 2 to 3. The numbers must be displayed SAE corrected to account for differences in ambient conditions of temp, barometric pressure, and humidity from the internal weather station. STD or Standard is not acceptable as it does not correct for this. If you really want to compare one car to another accurately, compare cars tested on Dynojets to another with SAE correction. Whether the numbers put seem higher or lower than another brand of dyno is a completely subject.
With all the other dynos, the numbers can be manipulated depending of how the operator loads the dyno, adjusts the ramping rate, adds in his fudge factor for transmission loss, etc. With a Dynojet, the load is fixed by the inertial load of the drum, and there are no other operator variables in the software available to alter the output. There is a reason racing organizations such as NASA only accept Dynojet runs.
With all the other dynos, the numbers can be manipulated depending of how the operator loads the dyno, adjusts the ramping rate, adds in his fudge factor for transmission loss, etc. With a Dynojet, the load is fixed by the inertial load of the drum, and there are no other operator variables in the software available to alter the output. There is a reason racing organizations such as NASA only accept Dynojet runs.
01-12-2012, 08:59 PM
#38
Nordschleife Master
none of this is worth a bag of donkey's doodahs. Grown ups take the engine out of the car and put it on an engine brake. That's it period - no discussion.
The chassis dyno has a function and that is to measure the incremental differences between different modifications to the engine/driveline in the same chassis.
As you are all aware, the elves at Zuffenhausen put every single engine on an engine brake and send back all engines which do not make enough power or make too much power. However, within the allowed output tolerances there is a noticeable difference.
For the dyno figures here, it would have been helpful to have the data for each vehicle before and after the mods were installed. Then you could have normalised the results for dyno and engine variations. Without that kind of information you are playing with the soap in the bath, metaphorically speaking.
R+C
The chassis dyno has a function and that is to measure the incremental differences between different modifications to the engine/driveline in the same chassis.
As you are all aware, the elves at Zuffenhausen put every single engine on an engine brake and send back all engines which do not make enough power or make too much power. However, within the allowed output tolerances there is a noticeable difference.
For the dyno figures here, it would have been helpful to have the data for each vehicle before and after the mods were installed. Then you could have normalised the results for dyno and engine variations. Without that kind of information you are playing with the soap in the bath, metaphorically speaking.
R+C
Stock
Akrapovic
Both 40 minutes apart
We have been swamped scrambling for winterfest, they will be posted
Car made no measurable peak hp but gained midrange hp and torque
The reason we did this was to to compare each others cars on the same dyno same day
The numbers mean something to us in that respect
01-12-2012, 09:38 PM
#39
Sorry but I disagree with a lot of the assumptions about chassis dynos here. I have tested and analyzed hundreds of 911s through thousands of runs on virtually every dyno out there (Dynojet, Mustang, Dynapack, Dyno Dynamics, Superflow, Maha, Land-Sea and others I don't remember) and the only one I see deliver consistent numbers are Dynojets. You can dyno a car on a Dynojet in Los Angeles and get the same wheel hp numbers on another Dynojet in New York within 5 hp, usually 2 to 3. The numbers must be displayed SAE corrected to account for differences in ambient conditions of temp, barometric pressure, and humidity from the internal weather station. STD or Standard is not acceptable as it does not correct for this. If you really want to compare one car to another accurately, compare cars tested on Dynojets to another with SAE correction. Whether the numbers put seem higher or lower than another brand of dyno is a completely subject.
With all the other dynos, the numbers can be manipulated depending of how the operator loads the dyno, adjusts the ramping rate, adds in his fudge factor for transmission loss, etc. With a Dynojet, the load is fixed by the inertial load of the drum, and there are no other operator variables in the software available to alter the output. There is a reason racing organizations such as NASA only accept Dynojet runs.
With all the other dynos, the numbers can be manipulated depending of how the operator loads the dyno, adjusts the ramping rate, adds in his fudge factor for transmission loss, etc. With a Dynojet, the load is fixed by the inertial load of the drum, and there are no other operator variables in the software available to alter the output. There is a reason racing organizations such as NASA only accept Dynojet runs.
Ranger (Sua Sponte)
01-14-2012, 07:42 AM
#41
Banned
Thread Starter
The numbers on a dynojet can't be manipulated, period. Our intention was to dyno all the cars same day, same conditions. Is a perfect tool to measure the differences, and gains or losses on cars. We use it as a tuning tool, and not only to brag about numbers.
To brag about numbers, we go to the track
We have back to back dyno sheets, same day, without even unstrapping the car.
To brag about numbers, we go to the track
We have back to back dyno sheets, same day, without even unstrapping the car.
01-14-2012, 07:44 AM
#42
Banned
Thread Starter
Trying to survive cheater fest, after a little drive thru the field, my car needed new brake ducts and a front splitter.
Ducts are already installed, and the new cup lip will be here in a few hours.
For now I need to thank the Greek, and Teo, for the extra parts.
Ducts are already installed, and the new cup lip will be here in a few hours.
For now I need to thank the Greek, and Teo, for the extra parts.
01-14-2012, 09:07 AM
#43
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04-06-2012, 02:55 PM
#44
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Ok,
So finally the numbers are here, I'll also update the other threads with this info.
This is Erik's 3.6 GT3RS - M&M catless headers, side mufflers delete, Stock center muffler
997FLA's 3.6 GT3 - Europipe straight pipes
Izzone's 3.8GT3RS - Akrapovic Cup system
Trakcar's 3.8GT3RS - Side muffler delete, Stock center muffler, GIAC tune
So finally the numbers are here, I'll also update the other threads with this info.
This is Erik's 3.6 GT3RS - M&M catless headers, side mufflers delete, Stock center muffler
997FLA's 3.6 GT3 - Europipe straight pipes
Izzone's 3.8GT3RS - Akrapovic Cup system
Trakcar's 3.8GT3RS - Side muffler delete, Stock center muffler, GIAC tune