highway speeds in a 4cyl yj.

[Jeremy]

ok its time to start thinking about building the yj. this is the first 4 cyl. jeep i have ever owned. what are some of my options for maintaining highway speeds with 33" tires.....same questions for 35" tires.

and i dont want any SBC answers.

 

[SAMI]

i have a toyota 4runner w/ 4cyl & 5.29's pushing 37's.. i ran 75mph+ MAJORITY of the trip to/from st george, faster most the way home... that's between 4th and 5th gears, 3k-4k RPM's just about the entire time..

 

[benjy]

I have a friend with 35's with the 4 banger, 4.10s and he was able to hold 70 most of the way to moab (between 3rd and 4th gear)

 

[red]

i dont know the letter classifications of jeeps (sorry just never bothered to pay attention) but for referance my sister's 97 SE wrangler (4cyl 5 speed manual) was almost floored to maintain 70mph down in houston Texas, hit any hill and 3rd or 4th was needed to maintain even 45mph. 31" tires.

 

[Skylinerider]

I have a 93 YJ and a 4cyl. I am running 32" tires and 4.10 gears (stock). I can do 70+ on level road no problem, but when a hill comes along, I lose speed fast, and have to shift into 3rd.

 

[Jeremy]

i dont know the letter classifications of jeeps (sorry just never bothered to pay attention) but for referance my sister's 97 SE wrangler (4cyl 5 speed manual) was almost floored to maintain 70mph down in houston Texas, hit any hill and 3rd or 4th was needed to maintain even 45mph. 31" tires.

thats what im dealing with now. 95 yj, 4cyl, 5 speed, 4.10's and 31" tires. i do not want to drive to moab in third gear.

 

[SAMI]

sounds like a slightly deeper gear in the diff'll help keep some speed on hills.. all sorts of hills comin from st george, and i think i needed 3rd once the entire way.. i dipped below 65mph maybe 2.5 times...

 

[ewander]

I ran my 4 banger YJ with 4.88 gears and 35" tires.....but it bugged the crap out of me. It was much better than stock but still weak. Your best bet would be to drop to 5.38s with 35" tires. I think you would be okay with 4.88s and 33's though.

Of course your stock axles will only go to 4.88s.

The insanity of driving mine on the freeway forced me to buy a jeep with a 4.0. Hind site, I should have kept my 4 cyl. and bought a tow rig (I tow my jeep now anyway).

Eric

 

[mesha]

My 4 cyl is 4.88s with 35s and I wish it was better. I don't know how every one else manages to drive 70 everywhere but I can't. I just got a 4.0 t.b.i and spacer in hopes that will help. I'll probably go to electric fan. I already have a flowmaster but might put in a header. I would go as low as you can in the diffs meaning 4.88s. All that said I pretty much tow it everywhere on my trailer anyway. Maybe I'll coat the whole thing in teflon to make less resistance.

 

[Jeremy]

i hate the idea of putting 4.88's and 35"tires on the lp d30.

i plan on replacing the front axle soon. but it wont happen before ejs. i hate to step up to 33" tires now nowing that i want 35"s when it is all said and done.

5.13's sound like the way to go. so i need a front 44 with 5.13's and some sort of locker.

i have a 9" rear that i need to get rid of the spool and 4.88's(or whatever they are 86 or 89 i cant remember) and get a detroite and 5.13's ( or what ever the 9" equivelent is)

 

[soda blaster]

before I changed mine I ran 33's with the stock 4:10 gears and it was ok it would do 70 or so just fine. I now have a 44 and 9 inch 513 gears with 37's and forget it, I trailer it only, going out to bfe I could get up to 35 maybe 40 tops

 

[ewander]

The Dana 30 in the YJ is high pinion, but they all have the center disconnect. While I never broke mine I had friends that needed to replace the center axle a couple of times. I did fairly hard trails and never broke a front axle with 35s. The 2.5L is easy on parts, even with the tera 4:1 t-case gears.

Good idea getting rid of the spool. I had a mini spool in my 8.8 and hated it around town.

i hate the idea of putting 4.88's and 35"tires on the lp d30.

i plan on replacing the front axle soon. but it wont happen before ejs. i hate to step up to 33" tires now nowing that i want 35"s when it is all said and done.

5.13's sound like the way to go. so i need a front 44 with 5.13's and some sort of locker.

i have a 9" rear that i need to get rid of the spool and 4.88's(or whatever they are 86 or 89 i cant remember) and get a detroite and 5.13's ( or what ever the 9" equivelent is)

 

[ewander]

You know, the electric fan did help a little with power and mileage. I was surprised. The flow master and open air filter were almost not noticeable. I wouldn’t waist your money on the header.

My 4 cyl is 4.88s with 35s and I wish it was better. I don't know how every one else manages to drive 70 everywhere but I can't. I just got a 4.0 t.b.i and spacer in hopes that will help. I'll probably go to electric fan. I already have a flowmaster but might put in a header. I would go as low as you can in the diffs meaning 4.88s. All that said I pretty much tow it everywhere on my trailer anyway. Maybe I'll coat the whole thing in teflon to make less resistance.

 

[d-stumph]

before I changed mine I ran 33's with the stock 4:10 gears and it was ok it would do 70 or so just fine. I now have a 44 and 9 inch 513 gears with 37's and forget it, I trailer it only, going out to bfe I could get up to 35 maybe 40 tops

you must have a factory jeep 3 speed automatic

 

[JoeT]

i do not want to drive to moab in third gear.

and I don't want to push your little YJ there either!

 

[Jeremy]

and I don't want to push your little YJ there either!

i am so glad i dont have to ride with you this year.

 

[rondo]

when i had my YJ on 33s and stock axles i had 4.56 put in and that wasn't low enough. Braking was scary too! i ended up wiping out the front axle. both axles are junk.
Now its on 37s and 5.38s and barely pushes 70 on flat ground.
If you're staying 35s i suspect your braking will be scary. Go as low a gear as you can.
if i was going to do everything all over again i'd start with a 6cyl jeep or engine swap.

 

[Greg]

For 35's I'd say 5.13's or 5.38's... you're going to have to spin that little 4 cyl to make the Jeep move. Have you thought about a turbo? I know it's been done by others, the Jeep would be more driveable on the freeway, as well as the additional power offroad.

 

[turbohaulic]

IMO get the new tires on and see how it does. My truck with 33's does better than my buddies with the same motor and gears. So you might as well try it out and then go from there.

 

[Jeremy]

IMO get the new tires on and see how it does. My truck with 33's does better than my buddies with the same motor and gears. So you might as well try it out and then go from there.

well if im having issues with 31's i dont think its going to be any better with 35's.

i really havnt looked into a turbo. does any body have a link to some quick info?