Big Fat Tires

[bjoehandley]

Whats the widest street tire you guys have put on a XJ, I'm looking at around 255/60-70/15 on my factory '97-01 Limited "mesh" style rims (I think they're 15x7)

 

[ILLXJ]

My son has 255/60R15's on his 92. I think they are on an 8" rim. We bought it that way so I'm not sure. JIM.

 

[Wolf]

My son has 255/60R15's on his 92. I think they are on an 8" rim. We bought it that way so I'm not sure. JIM.

Pics?

 

[ILLXJ]

Pics?

I'll see if I can get some this weekend. JIM.

 

[bjoehandley]

Cool ILLXJ, looking forward to it. Do you have any rubbing problems on the fenders, flares, LCA's, etc? Which brand tires are they too and how do they stick and run in the rain and snow as well as on twisty roads (my main reason for asking)?

 

[HaleYes]

I'll see if I can get some this weekend. JIM.

Here are ILLXJ's pics........

 

[BIG-G]

HAH, i have BFG/AT tires at 325/60/15's on my 95 XJ. They stick out way past the stock fender flairs. There mounted to am racing rims 15x10. They measure about 30.5 by 12.5 of tread!! They used to rub untill i took the grinder & did some trimming. I personally love the look and feel of em because tires that wide lower my center of gravity. Of course they limit me on trails somewhat. I got pics up somewhere on here.

 

[ILLXJ]

Cool ILLXJ, looking forward to it. Do you have any rubbing problems on the fenders, flares, LCA's, etc? Which brand tires are they too and how do they stick and run in the rain and snow as well as on twisty roads (my main reason for asking)?

Had very slight rubbing on the flairs when stock & flexed completely. Now it has a 3" lift & no rubbing any where. The rims are American Racing at least thats what the center caps have on them. The backspacing is 3.75 or 4", can't remember for sure. The tires are a no name all weather tire. They do very well in the rain & snow. We don't have much in the way of twistys around here, but it seems to stick pretty good in the corners. The jeep is very stable even without the rear sway bar. Just for comparison the jeep in the middle has a 3" lift & 30's. The other one has about 6" & 31's with trimmed fenders. HTH. JIM.

 

[Wolf]

HAH, i have BFG/AT tires at 325/60/15's on my 95 XJ. They stick out way past the stock fender flairs. There mounted to am racing rims 15x10. They measure about 30.5 by 12.5 of tread!! They used to rub untill i took the grinder & did some trimming. I personally love the look and feel of em because tires that wide lower my center of gravity. Of course they limit me on trails somewhat. I got pics up somewhere on here.

http://photobucket.com/albums/y26/big-g/ :wave:

 

[explorer]

I personally love the look and feel of em because tires that wide lower my center of gravity.

I generally prefer narrower tires, but if you can show me how to make wider tires lower my center of gravity, please do. Thanks

 

[BIG-G]

I generally prefer narrower tires, but if you can show me how to make wider tires lower my center of gravity, please do. Thanks

When u have 12 solid inches of tread on the ground it is harder to tip over then 8 inches of narrower tread. On pavement this is a FACT. Offroading is different and u would benefit from a narrower tire or just one that isnt as wide as mine.

 

[explorer]

When u have 12 solid inches of tread on the ground it is harder to tip over then 8 inches of narrower tread. On pavement this is a FACT. Offroading is different and u would benefit from a narrower tire or just one that isnt as wide as mine.

So is the CG lowered inversely proportional to the difference in tread width? IE: 4" wider tire= 4" lower CG.

 

[BIG-G]

Well i dont know the converion chart by how many inches it is reduced by but it is sheer mathematics that any vehicle with an agressive wide tire will cover more ground and there for it makes it harder to tip over (atleast on pavement).

Think of a race car, a stock nascar runs a certian size tire so would you take them off and put a narower tire on?????

 

[XJEEPER]

Lame....increased tire width does not lower the CG, but improves lateral stability. Other factors are sidewall, rim width and BS. These determine how much the tire will roll or deflect when subject to lateral forces when cornering and the overall stability of the vehicle.

To answer the original question, if you want to go much wider in tire than a 255/60 series, 8" wheels would be better. You could then go with a 275 or 295, without too much "tire roll" when cornering. Jumping up to a 16x8 will give even better results as you can will have a smaller sidewall section which further decreases roll, but you will also have a slightly stiffer ride to factor in, due to the smaller sidewall.

 

[gac_gonejeepin]

Lame....increased tire width does not lower the CG, but improves lateral stability. Other factors are sidewall, rim width and BS. These determine how much the tire will roll or deflect when subject to lateral forces when cornering and the overall stability of the vehicle.

To answer the original question, if you want to go much wider in tire than a 255/60 series, 8" wheels would be better. You could then go with a 275 or 295, without too much "tire roll" when cornering. Jumping up to a 16x8 will give even better results as you can will have a smaller sidewall section which further decreases roll, but you will also have a slightly stiffer ride to factor in, due to the smaller sidewall.

:lecture: --yup he pretty much covered it right there.

 

[bjoehandley]

:lecture: Yup, that's some of what my criteria was.

I wanted to keep in the 60-70 series to keep the sidewall for ride (it's kind of a family truckser right now) and go wide for better handling, and I've read where (and had some experiance with my Lebaron) that a 60 series tires on a 15" rim will offer the best average between rotating mass and size while giving good break away characteristics at the limit, especially since I wasn't going to try and put huge brakes on it.
One thing my Dad has noticed on his '88 and '90 that he got considerably higher milege out of the tires when going to 235/75/15's on them (I think the '88 had 225/75/15 and the '90 225/70/15)

Thanks Guys :wave:

 

[XJ Saga]

Also consider that the sizes of tires you are discussing will add considerable weight, example: 235 from 255 or higher could add up to 20+ lbs per tire, not including the wheel. If you are looking for a street XJ, I would at least keep this in mind as it will affect your off the line performance in addition to speedometer, fuel mileage etc....more rolling mass is not good at all IMO.

 

[BIG-G]

Well thats what i ment anyway,, that the wider tires will keep u planted on the grond better. I used ground clearance as an example to this.

U guys are running 235/60/15's to 255/70/16 and i have 325/60/15 so i know the difference from stock to way wide.

 

[theslacker]

235 from 255 or higher could add up to 20+ lbs per tire.

I don't think an extra 20mm of tire tread is going to add 20lbs

 

[XJ Saga]

I don't think an extra 20mm of tire tread is going to add 20lbs

You are looking at 10lbs of more rubber, minimum.

255 "and over" will add up to 20lbs per tire depending on tread pattern etc.