Hello all. I have an 07 Unlimited Rubicon. I couldn't afford new rims so I bought the largest tire that would fit (295/70R17) which is roughly a 33 1/2. Obviously there was a noticable bog in power that ultimately could be solved with a re-gear but that isn't an option at the moment.

I am wondering if any of you have same vehicle (Rubicon with 4:10's) and are running 285/70R17 (33's) tires and if you noticed a huge difference in power? I am considering dumping these tires and going back to a 33 (285/70R17) instead of keeping these 295/70R17's.

Not expecting a huge dirrerence in going back only 1/2 inch but I won't know until I ask...

Thanks for your input, always appreciated!

Paul.

 

Turn O/D off, and browse the Superchips Flashpaq threads.

If you can afford to take a loss on your current tires and buy shorter ones, I'd guess you can afford the tuner...

 

90% of my driving is with OD off~thanks. I will look into the superchips idea now.

Since my tires are just about new I can sell them and only take a small loss. Either that or I can run them until they need replacing and drop down to the smaller size.

Are you a happy user of this Superchips programmer?

Thanks, Paul.

 

I'm running 305/70/17 (about 34.5") on my 07 Unlimited with auto tranny and 4.10s. I love it. Will I regear some day? Probably, but I don't find it to be too bad just the way it is. That said, my OD button is always off.

 

Thanks for the input. I will probably run these until...

Question, did you replace your rims??? If so, how wide did you go?

Thanks!

 

Currently sitting at 161 pages of generally favorable input. Enjoy.
https://www.jk-forum.com/forums/show...al-Impressions

And yes, I like the flashpaq so far. I honestly did not notice any 'seat of the pants' power increase, but shift points and mpg's are better, and I can hold freeway speeds much better without the downshifting I had before. (Haven't noticed much difference in town, but highway mpg's went from 16 to 19, which isn't too bad with the elevation changes around here. The added range before re-filling is definitely nice...)

 

I just bought a BDS 3" lift and plan on running 35`s and i`m wondering what it will do to the power/speed but im not running an auto pilot i have the 6 speed manual. any input is appreciated!

 

I put the same size of tire on my 2 door. The mileage dropped to 15 mpg.

Then I reset the wheel circumference with an aeroforce scan gauge. My mileage went back to 18 mpg. Big surprise to me. With your gearing, if you adjust the shiftpoints you will be real happy with the result.

I ran mine up over Loveland Pass last weekend, no problems and ran 65 wherever it was posted.

 

since you are running an automatic i cant vouch for much but im running 34.5 with 4.10 6 spd and it seems pretty peppy to me still.

granted i lost a little powere in 6th gear but thats only when crossing steep bridges.


i dont think everyones engine was built equally
i think some of our 3.8s work a little bether than others so that might be the case too

 

Thanks ya'll for the input; seems I got some homework to do.

Will let you know what I figure on doing.

Thanks again, Sodapop.