gear ratio
 

i am running a 1968 mustang set up like a stock eliminator car. the car has a 428cj, pro shifted toploader and 4.56 rearend. the car ran a 10.85 at 127mph. do you guys think it would et better with say a 4.88 gear? thanks ron

Re: gear ratio
 

Use formula to gear for rpm you want @ finish line MPH X Gear ratio X 336 divided by tire height=RPM
Mike Taylor 3601

Re: gear ratio
 

^^^What he said^^^

But Yes you need a 4.88

Re: gear ratio
 

if you where to use radial tire or bis ply tire is it the same formula????

Re: gear ratio
 

you would change tire height in formula,if you were trying to get that precise,but I don't know how tell how much tire growth would happen, rim/tire width,mph, sidewall etc. would all have to be factored.
I always have just used height on sidewall or mearsured and is close enough,any growth that happens is just a little cushion that keeps you from going over.
I have always geared by this formula IE if want to go through @ 8K gear so I get as close to that # as can.
Mike Taylor 3601