This is the best calculator / converter that I have found on the net. I hope the link works. Give it a try, it takes a buch of guesswork out of swapping gears and tire height and true speed vs Rpm's. http://www.dakota-truck.net/TIRECALC/tirecalc.html
this ones my favorite, calculates for auto tranny and overdrive automatically http://www.csgnetwork.com/multirpmcalc.html
This is a commercial site but part way down the page there is a chart that lets you figure out what gears you need in the trans to correct a speedometer. Plus it has plenty of speedometer drive gear info in it. http://www.transmissioncenter.net/s...______va.htm?gclid=COuhyPaegJYCFQEziQod3SGNeQ There is a pretty good list of useful info here http://www.hotrodworks.net/hotrodmath/hotrodmath.html anther one http://secondhandpower.tripod.com/autocalculator.htm
No class. I use an Isky Dream Wheel that has Ford and Lincoln gears as well as Chevy three speeds from '56. It was given to me by Ted Gotelli from his tool box after he gave up the Top Fuel wars. I'll keep it forever.
Yep...good old analog computerator! Mine came from the glovebox of a junked '46 Ford in about 1962, when I was 14, so it represents a generation before me even... I've spent hours squinting at the little lines and guesstimating exactly where 4.44 should be... They're being made again, but I understand they no longer have the ratio call-outs.
Pete over on FordBarn made up a spreadsheet with all Ford/LZ ratios, tire sizes, and so on in it somehow ready to calculate everything out to lots of decimals, but it was waaay too smart for me. I bet if I'd been able to show it to Ed Iskenderian, he would have showed me a really creative way to use the computer as a wheel chock... Just discovered the Isky Dreamwheel is fully compatible with this PC! It fits neatly in the retractable cupholder thing, and I can just push the button and out it comes, ready to COMPUTE!!
63,360 inches in a mile. Tire diameter x 3.14= circumfrence. 63660 divided by 86.35 = 737.23 = RPM of 27.5" tall tire at 60 mph = number of tire rotations in a mile. Multiply by gear ratio to get driveshaft and crank speed in 1:1 high gear without overdrive. If you want to change MPH, divide by calculated MPH (60 in this case) and multiply by target MPH. Works for tire and crank RPMs. I use this on a regular basis.
The Jalopy Journal
