Is there a rule of thumb on tire size and RPM's? [Archive]


Pirate4x4.Com > General Tech > General 4x4 Discussion > Is there a rule of thumb on tire size and RPM's? PDA : Is there a rule of thumb on tire size and RPM's? nakona 05-13-2002, 02:44 PM For whatever size tire you have, how do you estimate how far your RPM will drop at a given speed with larger tires? Rubicrawler 05-13-2002, 02:59 PM It's a direct percentage:rolleyes: If you increase your tire size by 10% your engine RPS will drop by 10% at any given MPH. So if you run around 2800 RPM's @ 60 MPH with your bald 31's and you jump up to new 33's (about 10% height increase) your RPM's @ 60 MPH will drop to 2520 RPM's :) Erich In AZ 05-13-2002, 03:09 PM Here are a couple of good links if you want to get an idea what tire size and gearing will do for you: Gear Ratio / Tire Size Table http://www.4lo.com/calc/geartable.htm Tire size Calculator http://www.4lo.com/calc/geartire.htm nakona 05-14-2002, 10:54 AM Thank you Erich. Those are two of the most useful automotive links I've seen in a long time. tigger4x 05-15-2002, 12:14 AM Originally posted by nakona Thank you Erich. Those are two of the most useful automotive links I've seen in a long time. No doubt!! THANKS ERICH!! :beer: