I don't know what manufacturer of dyno my car was tested on, but I'm quite sure it was the inertial type. Does any info need to be plugged into the dyno? For example, do you need to "tell" the dyno what type of car is on it and what gear ratio you'll be using for the pull? Seems to me if the dyno measures your horsepower by how quickly your motor can accelerate the drum, the dyno would at least need to "know" your gear ratio otherwise 3rd gear pulls would show a lot more power than 4th gear pulls?


[Modified by 4doorH22, 11:30 PM 9/10/2001]

 

ttt

need to know!

 

Yes, dynoing in 3rd would give a higher number.
Just do the pulls in 4th, that will be the most accurate.

 

They try to dyno whatever car you're running in the gear that's closest to 1:1 for better accuracy.

 

Honestly, on most all HOnda's your going to get almost the same number with 3'rd or 4th gears.

I don't know how many times I have done 3rd and 4th ger pulls backs to abck to figure it out....its like the exact same thing.

I use 3rd for all-motor cars because its comfortable, and 4th for turbo cars, because, obviously, if you use 3rd on a turbo car, you will doa burn out on the dyno....I even do burn outs in 4th when its like a 400+ HP car.

Jeff

 

Thanks for the replies. So I take it absolutely not data is input into the dyno?

 

Ok, all BS aside, her is EXACTLY what I input into my dyno...

Altitude.

that is it...NOTHING else..

And I have dyno'd cars putting in 10,000 feet, then next pass 0 feet. And the difference is so minimal, I can't even notice it. Its like the difference between 3rd and 4th gear...its very hard to say
"yeah, that was different"

The dyno is not a super accurate instrament....you don't get exactly the same HP every pass on a Dyno jet...

you might if your car is like 100 HP...but when your car is like 160 HP at the wheels, it differs under .2% or something...or up to that..

Plus the difference of temperature in oil, water, intake manifold...alot of variables...

the purpose of the Dyno is to tune a car. You start at one setting, and you try other stuff to make power. So it doesnt matter if all your input, on the older dyno's is wrong, because as long as its consistent, you can tune the car effectively.

My rant.

haha.

Jeff