And some doubt the usefulness of spreadsheets. I'm a junkie! Keeping everything else the same, And incrementing the tire Circumference by 1/16, the speed goes up about 1.1 mph faster from 33.5 - 34.5.
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How do you account for stagger, which tire is driving it forward and the combined effective circumference between the two tires because of tire slip?
As usual because the OP stated it's a dirt oval kart your spread sheet is again totally useless.
Even if it was a sprint kart in a turn with the inside rear not fully unloaded wouldn't the partially engaged inside rear slow the kart because it's engaged?
And then if it's slowing the kart any at all doesn't it then mean the outside rear has to be slipping?
On a straight with a sprint kart going exactly straight yes your spread sheet would be valid.
But in every other case including the stated dirt oval situation your spread sheet will give an incorrect answer because of stagger.
You like to ponder on your spread sheets ponder about it being incorrect in all but one case, which is not what is being asked on here.
Al, you really enjoy asking others to do useless stuff for you and report back.
Have you ever in your real years of kart racing taken a radar reading to see if your spread sheets are accurate on a sprint kart going down a straight?
After thunkin and writing the above I have a thought for the OP.
I think radar guns are not that expensive anymore, wouldn't it be fun to do the calculations noting highest rpm on the straight via the tach and compare it to actual speed taken from a radar gun?
Up front i'd bet actual speed is below every time with a dirt oval kart butt I ain't so sure and I think it would be fun to compare on the track.
hummm... out to look for a cheap radar gun.
Now I'm thinking it would be great to know which variables like stagger, tire compound, prep, air pressure with like top speed calculations will 'really' increase top end speed.
With cars it's common place to reduce stagger when the track gets slick, I think for grip reasons mainly in turns.
But how much change does what and I've been told many times by experienced racers(not really believing them if full) that they run 13"s of stagger no matter what all the time.
I wonder now if a stagger reduction because the track slows is really what's needed.
It's probably one of those things you don't need proof to do because it just works or seems to work, with the real question of did I do enough change or was it too much.
Thanks Al, started out poo pooing your spread sheet calculations and it lead to thunkin about the radar comparison thing and other stuff.
... wow, ain't this dirt racin stuff easy? ...