Dynodynamics question
There will be a difference in drivetrain losses, but I don't know the extent of that difference. There is no wind resistance on the dyno, so that removes a HUGE part of the real-world difference.
Originally Posted by Smogrunner
Ted,
Isn't there more whp loss due to the drivetrain and wheels when dynoing in a higher gear? It just seems that a car would lose whp due to having to spin four tires at 110mph vs. 80mph.
Isn't there more whp loss due to the drivetrain and wheels when dynoing in a higher gear? It just seems that a car would lose whp due to having to spin four tires at 110mph vs. 80mph.
Originally Posted by Ted B
As for the graphs illustrated in the initial post, they look like they came from different cars. Nevermind the power numbers, the power peaks aren't even the same rpm!
as for the reasoning of me starting this thread.
Originally Posted by DynoFlash
Looking at your sheets - its obvious that the tune is very well done and it has held well over time. I think you should be happy with your obviously very well running car and don;t pay too muach attnetion to dyno numbers. The main point is that the car runs smoothly and safely and makes good power - the number itself means little.
OMG!!!!!!!!!!!!!!!
I agree with you Al. That was very well put.
Here is to learning!
Well I do now have Helix intercooler piping kit on the way. Do you guys think it will mess with my custom tune very much or mess with my a/f's? Would I need a retune for just piping?
Originally Posted by Dyno4mance
IMO Nope>>>>
sweet, I trust your and shiv's word. Guess it will be next visit to you Andrew (not the dyno day, but ill be there) or whenever shiv is back that I can get a new tune since list is full.
Originally Posted by Ted B
Yep, a DD will *always* read lower than a DJ. As for the graphs illustrated in the initial post, they look like they came from different cars. Nevermind the power numbers, the power peaks aren't even the same rpm!
If we think about it, so long as the load applied by the dyno is constant, the hp needed to accelerate the wheels is the same between different gears. What happens however is the change in speed of the rollers in a run taken in a lower gear is less. This could possibly translate to less resolution of the power curves, but the overall result is dependent upon the dyno software. So long as the dyno computer can monitor rpm, I think the results between gears will be similar. This was not true for the old dynos, which were largely mechanical.
If we think about it, so long as the load applied by the dyno is constant, the hp needed to accelerate the wheels is the same between different gears. What happens however is the change in speed of the rollers in a run taken in a lower gear is less. This could possibly translate to less resolution of the power curves, but the overall result is dependent upon the dyno software. So long as the dyno computer can monitor rpm, I think the results between gears will be similar. This was not true for the old dynos, which were largely mechanical.