Never seen this formula before,,,,,always open for NEW stuff,,,ran my car's numbers through this....the numbers come out just about exactly what I thought my car OUGHT to do. Like others,,I'm off about .3 in 1/8 and 1/4. I only have about 50 passes on my car though, and still trying to get 60' where they should be(my estimates)...so I would say, the formula is pretty close!!

It shows me being off .13 in the qtr.

Hmmm..... I'm off by1/10 in the 1/8......, .5 in the 1/4

looks like most are in the ballpark to see this formula's value.
Anybody have ideas why it works?

Got if off the UMTR website a few yrs back and it has been a helpful indicator as to a gearing or slipping problem.

Plus easy to see with simple calc who may be back pedalling etc.

well using those formulas i'm slow to half track but faster at the stripe. so how do we fix that?

Cant answer that.
You know your configuration, what is that indicating?
What are the numbers?

Good calc. Mine is 1.0 off in 1/4 and 1.1 in the 660. Perfect.

I can't figure them numbers out. Going by the 60 ft., I'm .1 faster for the 1/4 ET, .04 slower in the 1/8 and it runs mph 3 mph faster than the calculator in the 1/4

that kinda makes sense to me.
good 4 gear launch with bite makes for excellent 60 ft time.
then you get to shifting and maybe just not as efficient as the first 60 ft .
then compound all the gear chnges and your down on et with mph still there.

Possible?

at any rate thats pretty close numbers for such a simple calc.

I ran my numbers and I'm .3 off in the 1/8 and .2 off in the 1/4. I average 23.7 mph gain from 1/8 to 1/4. I know that I have some more suspension tuning, but this seems like a lot. Do the numbers vary more with heavy cars?

Just ran my numbers... I am off .2 in the 1/8th but only .02 in the 1/4...Now I am confused!