Brock's dyno...?

[Draco1340]

This equation is increadibly crude, but increadibly accurate.

Rear Wheel HorsePower = ( MPH/234)^3 x Total Weight.
203 HP will push a 700 pound vehicle to 155 mph in the quarter mile.

Unless you completely botch the launch, your MPH is a pretty accurate Dyno given the temp, baro, and RH on that given day.

 

[GPW]

4th gear is usually the only 1:1 ratio gear (unless there was some sort of sprocket change) so to influence numbers the least that gear is used for peak power numbers. How the low end is tuned is done differently across the board.....key word is LOAD.

Something they said in a class three years ago...tuning is really easy once you learn the math and read power charts disregarding AFR all the time. The math is super simple. I use a calculator at times when in a big hurry.

 

[ToXSicK RoCKeT]

Ok, let me ask this way......if I have already changed my gearing(-1 counter +2 rear), What gear should my busa be dyno in?

 

[ToXSicK RoCKeT]

This equation is increadibly crude, but increadibly accurate.
Rear Wheel HorsePower = ( MPH/234)^3 x Total Weight.

Draco, in the formula above, what does the ^ represent? Thx

 

[Mr Brown]

Ok, let me ask this way......if I have already changed my gearing(-1 counter +2 rear), What gear should my busa be dyno in?

You want to dyno it in whatever gear is 1:1, or as close to it as you can get. I think there's a gearing chart on here somewhere that will tell you how the ratios change when you add and subtract teeth. If you do it in a higher gear, it will show more power than it's really making.
Draco: I agree, but getting your a/f close on a dyno will make your work easier when using a datalogger. Plus some of us are broke and have to use a butt datalogger......

 

[rdd102781]

Draco, in the formula above, what does the ^ represent? Thx

Normally, in math that means 3rd power. I am not sure if that is what he meant it for, but Ordinarily that is what it means. AKA multiply the sum of Mph/234 times itself three times. In the equation that he gave above the mph=155. So it would look something like this 155/234= .662 next you would do .662*.662*.662=.290117528 then multiply this number by the weight, which is 700. .290117528*700= 203.08. Hope that helps.

 

[ToXSicK RoCKeT]

Normally, in math that means 3rd power. I am not sure if that is what he meant it for, but Ordinarily that is what it means. AKA multiply the sum of Mph/234 times itself three times. In the equation that he gave above the mph=155. So it would look something like this 155/234= .662 next you would do .662*.662*.662=.290117528 then multiply this number by the weight, which is 700. .290117528*700= 203.08. Hope that helps.

Ahw ok.....Gotcha, Yes that HELPED ALOT! Thank You

 

[BusaWizard]

 

[oldschool]

You want to dyno it in whatever gear is 1:1, or as close to it as you can get.

This is correct.

I would also like to add that the correction factor adds more "correction" to the number the further away from 1.0 you get, either + or -. If you look at the graph in post #3 you'll see a correction factor of 1.04 and 1.06. If you compare that to the raw uncorrected number you will see a larger deviation from the raw number it actually made as compared to a pull with a 1.0CF.

In contrast look at post #6. Those three pulls all have a .99CF which is close to the 1.0 standard and therefore has less "correction" applied to the corrected number.

In the end they are just numbers but it is a good tool to have and use.