Fastest Ive ever gone in a YJ was 93 in a complete stocker I believe that will never happen to me again. With the 2.5L and 33s 4.88 is the correct gear ratio to return to factory power. 4.88s with 35s would be like 31s with 4.10s, to put things into perspective.
My four angry squirrels are still stock other than 3/4" shackle lift and 31s with tube fenders-
I can hold 80MPH easy on the highway (GPS verified speed, I believe speedo shows 72 or something), although this is in IN where we don't have too many real hills.
I am dropping in some s10 leaves for a bastard pack lift, an 8.8 with 4.56 gears and doing 4.56 gears in the front and bumping up to 35s. I am still looking for a set of 33s for daily driving and keeping the 35s for trail (I DD my YJ 40 miles each way to work).
I also have a 4.0 TB and spacer to drop in, an AX 15 (still need to find a Dakota bell housing) and a laundry list of other stuff to add. I collect parts faster than I can get them installed... mostly because I hate working in the cold and my garage is too full of parts to fit the Jeep inside at the moment (got a 4.0 on a stand and 4.2 hanging from the cherry picker, going to build a 4.5 stroker, although current thinking is to put that in my XJ).
I am OK with the power I get from the 2.5, although that may change once I go bigger than the 31s I am running now. On 31s it is just fine-not a rocket but who needs to go fast in a YJ?
Im running 4:88 gears with 32-11.5-15 tires and can pull 65 - 75 mph in 5th gear almost all the time on local freeways. I still try to stay away from 33" tires because I can still feel a difference over the 32" tires.
My wife is running 31s with a 92 Wrangler 2.5. Like they said, 5th gear isn't worth the effort. 55 mph in 4th is comfortable to cruise with. Small lift and stock gears. No additional mods except a brute force intake. Mpg is prob 17 highway. Running on some of the WA State Mt passes it drops below 50 mph.
Yes I realize this is 2 years old, but the information is still relevant.
Another stock geared 32" kinda guy here...I can run 70 on the highway in 5th, even up shallow grades, and obviously, perfectly fine around town. I moved up from 31's, and would never go back.
I'm on 31x10.5s and have no problems. 75 on the freeway in 5th, easily hold 65 up steep grades in 4th gear.
Originally Posted by StanF
32s + 2.5L + AX5 + stock 4.10s = useless 5th gear and general poor highway performance.
Around town and offroad its fine.
Something is wrong with your rig then. I have 31s and can easily hit 80 still on the freeway. It may take me a bit longer than a 4.0 to get up to speed, but once there it holds it fine. I can make my 20 mile commute with hills in 5th the whole time at 70+...
Originally Posted by WidowYj91
I can run 90 with this setup on an old very worn out 2.5. My whole highway driving range is under 2700 rpm.
Ditto. My 2.5 sits at around 2800-3000 rpms from 70-75mph.