1998 4l60e fbody gear ratio change

[tim209]

hey guys, my eyes are bleeding from 4 hours of reading yet again tonite lol

what i have is
1998 z-28 doner that i put in my ford ranger(this is a short track racer only)I really only need 1st 2nd and barly 3rd gears.
the ecu was done by painless wiring. but i forgot to have them do the gear ratio changed. The rear end is 4.10 tire size is 33inch by my calculations that gives me 5.20 ish. stock tune for this car(z28) ratio befor swap is 7.71

when i try to change the ratio in speedometer it tells me invalid new tire/gear ratio
I know i prob missed somthing somewhere in all the reading ive done but...
I think this must be for the98 only cause i checked newer years (stock tunes) and it has a calculator in the speedometer...

Side note my future plans are to tweek the shift points to stay away from 4th always. think if i drag 1-2nd out more in mph this can be done..?/?

Dont know but its bed time .. give for the night

Thanks Guys

[Bill@HPTuners]

According to my calculator 33 inches divided by 4.10=8.04, not sure where you are getting 5.20???

[tim209]

Thanks Bill, I guess i was using the math backwards..lol I did mention my eyes were bleeding.