No, because increasing the tire diameter has the same effect as installing a numerically lower gear ratio. By upping the tire diameter and increasing the axle ratio by the about same multiplier, the overall relationship of engine RPM to vehicle speed remains about the same. That means that the torque applied at any given combination of road speed, gear, throttle position and engine RPM is about the same.

The whole point of changing the axle gear ratio is to make up for the torque loss caused by installing the larger diameter tires.

The issues of road friction, aerodynamic drag and tire mass are separate from the gear ratio calculation. No matter what you do, the larger/wider tires and lift create greater frictional losses that must be overcome by energy produced in the engine. Also, the additional mass of those big tires must be accelerated any time the road speed increases. For any given acceleration rate, the engine supplies more energy to the drive train to change the speed of the heavier tires.

And, of course, all of that energy comes from the chemical energy of the gasoline used.

 

ok, that helps... i wasnt thinking into it that hard i guess

 

i have 35s and 4.56 i get between 15-19 all the time. all city is normally 16 and highway from indy to muncie to see the GF i get about 17-18 at 65-70 mph... im thinkin of goin 4.88s on mine as im gonna be buying some 37x12.50 truxus MTs when i can afford them.. so if i do that ill let ya know and you can get a sweet deal on a set of 4.56 front and rear... and yes i have all of the tools and knowledge to install them in a timely manner at the moment there is only about 9k on the gears.


remember im only bout 2 hrs south of you

 

sweet. ya let me know i may be interested!

 

Zach, I usually get 15-16 MPG with my 35s, 4.88, and S/C on my 3.0...It's the same when I had my 33s, 4.10 and Non-S/C..

 

sounds liek if i was to regear and run 35s my mpg wouldnt be that bad at all.

 

and i can still kick the crap outa them damn wanna be ricers around here





by wanna be i mean the guys that just toss a fart cannon on then do the "show" mods

 

did you run 4.56s with 33s?

 

oh ya it would be about the same as when you where running 4.10's with your stock tires if you can remeber that far back LOL

 

mmm sounds like fun.

 

Im getting 4:56's with 35's. shouldnt be too bad

 

i did run the 4.56 with 33s.. it was noticable and i didnt really notice a drop off when i tossed the 35s on

 

mpg changes with the 33s and 4.56s?

i plan on 35s but i might not have them when i get gears.