The best I can determine, increasing the tire diameter by about 2" would effectively be equal to a rear gear ratio change of from 3.31 to 3.55.
Is that right?
Does changing the tire size have the same effect as changing gears?
I know I must be missing something here.
Try using a rpm calculator online. You can plug in different tire heights, and gear ratios to find your rpm at a certain speed. Easy to play around with to see how each affect each other.
I'm looking at a few different sites and can't agree. (Yet) I'll look again. lol
Look at this site and match 27" with 3.31 to a 3.55 ratio and you get a 29" tire. Gear Ratio and Tire Size Chart - HowStuffWorks
Let me add my 2 cents here for clarification.
A numerically higher gear is a lower gear and a numerically lower gear is actually higher numerically.
Confused?
4:10 is a lower gear than 3:55 but it's higher numerically because the numbers are bigger.
It's the ratio that matters. The pinion will turn 4.11 times while the axle will turn once.
The width doesn't matter too much. Its more the sidewall. Which remember is expressed as a %.
The difference between say a 275/35-18 and a 305/35-18 is only .8" so its not a huge difference. Might feel like going from a 3.15 to a 3.00. You most likely won't feel a difference.
Now say you went from a 275/35-18 to a 305/40-18 then its a difference of 2" and you will notice the difference.
When I ordered my MPT tunes, they wanted to know the gear ratio as well as the tire size. All are factors in tuning for my V6 auto. Just 2 more cents :thumb:
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Related Threads
?
?
?
?
?
Mustang Evolution Forum
2.1M posts
50.9K members
Since 2003
A forum community dedicated to Ford Mustang owners and enthusiasts. Come join the discussion about performance, horsepower, modifications, troubleshooting, racing, and more!