Mthis goes to the dyno!
#26
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2011 GLK 350, 2013 GT-R, & 2013 RAM 1500
Mo, I agree with you 100% about one dyno to the next not being comparable (I'm pretty sure my post said most of what you just said
), but I actually meant run to run variability in the same session on the same dyno. My personal experience on a couple of different dynojets (with different operators) has been that it's hard to get a reliable baseline, even on multiple runs in one session. I can't comfortably say my car has 470 rwhp (just a number) because it's the average of five runs when the variation is from 455-480. I'd rather have five runs that read between 454-457 and say that my car has 455 rwhp. It's a lower number, but statistically valid. And if you know the correction factor on a repeatable dyno, then you have legit numbers to work from. Yeah, I'm a nerd like that, but there's a lot of claims made in this industry based on a single dyno pull and I'm starting to believe there really isn't much validity in that method.
Just saying...
Josh
![naughty](https://mbworld.org/forums/images/smilies/naughty.gif)
Just saying...
Josh
![](https://lh5.ggpht.com/_NDnQlNKwG4c/S0_iJdzQOVI/AAAAAAAACJc/_7-2O0AvqsM/s800/C63_K1_vs_M5_Stock.jpg)
#27
I'm glad I qualified by saying it was my personal experience, but I've heard similar things from others as well. It seems like there's an art to running a dyno properly. Definitely more to it than "just strap it down and run it."
Josh
#28
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2011 GLK 350, 2013 GT-R, & 2013 RAM 1500
BTW, I really appreciate reading your posts/threads. They are always well written and filled with solid information. It is great to have someone like you on the boards.
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#29
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E63 P30, CL500 Sport
Mo, I agree with you 100% about one dyno to the next not being comparable (I'm pretty sure my post said most of what you just said
), but I actually meant run to run variability in the same session on the same dyno. My personal experience on a couple of different dynojets (with different operators) has been that it's hard to get a reliable baseline, even on multiple runs in one session. I can't comfortably say my car has 470 rwhp (just a number) because it's the average of five runs when the variation is from 455-480. I'd rather have five runs that read between 454-457 and say that my car has 455 rwhp. It's a lower number, but statistically valid. And if you know the correction factor on a repeatable dyno, then you have legit numbers to work from. Yeah, I'm a nerd like that, but there's a lot of claims made in this industry based on a single dyno pull and I'm starting to believe there really isn't much validity in that method.
Just saying...
Josh
![naughty](https://mbworld.org/forums/images/smilies/naughty.gif)
Just saying...
Josh
![thumbs](https://mbworld.org/forums/images/smilies/thumbsup.gif)