I was mounting these up, on my little Chinese machine, for a friend, and I've toyed with the idea of 255/70R15s. Now I've tried these, a 285/70 would be too close to rubbing, but a 255/70 should clear.



And just in case anyone had any other ideas:



That's how it would be.

 

Why put truck tire sizes on your car? What's wrong with the stock 15" tire? A 255/70 is almost a 30" tall tire.

 

Sometimes even 2.47:1 gears and a 0.696:1 OD with a lockup torque converter won't get the cruise RPM low enough with 26" tires. 29s fit, obviously, so why not? Or, I could go for 255/45R20s or 285/40R20 sand still end up at 29"
Maybe you don't remember when PHR did their Econo-Performer II '67 Camaro convertible? Back then, there were no 20s. Maybe the glory days aren't for everyone, but with 18s and an LSx for my '94 Camaro, and my '86 being the best platform for trying a big block, the 255/70R15s just seem more appropriate, since ultimate performance isn't always the goal.
But someday someone else may wonder how much can fit. Here's 2 pics of a 29" tire.
This test fit kinda got me thinking Mad Max, post-apocalypse stuff.
I do appreciate you asking, trying to learn, just being curious. Thank you for that.

 

those all-terrains kindof make me wonder what a set of super-swamper boggers would look like on the back...in keeping with the mad max thoughts

 

I couldn't sleep, so I was studying Moog's master list of all their coil springs. I think I'd order a pair of their CC845s if I wanted to run dirt roads on tires like these. Up front I'd have to experiment. 5406s might be good for washboards, but for a compromise I could live with on the street, I think 80090s. For actual rocks at low speeds, like the old man who took the white Crown Vic to Moab, I'd try 5778s. After removing the bumpers, of course.
I feel fairly sure a 225/70R15 would fit up front on stock springs, with these taller coils a 215/75 should be easy.

 

http://www.streetfire.net/video/top-gear-usa-season-3-episode-6-2592012_2398109.htm

 

Maybe this is making me deranged. I went to the library and found a guide to all the dirt roads in Utah. Difficulty ratings, GPS coordinates, points of interest, campgrounds, trail conditions, the lot.
Today I'm trying the 235/75 on the front, with turning.
Meanwhile, I'm thinking of ordering cheap Chinese 245/70R16.

http://www.discounttiredirect.com/di...0&rd=16&cs=245

or

http://www.discounttiredirect.com/di...0&rd=16&cs=245

The math says a 4.10:1 gear should be plenty for a 350 / 700R-4.
More pics in a few hours.

 

 

 

The cheap way to try this is retread tires.
As this is a RWD road car, airing down the tires ain't happening.
I'll want to keep the car up and safe, and LT tires will reduce the risk of a sharp rock stranding me.
https://www.treadwright.com/individu...225-75R16.00-E
The tires could always end up on my big van, so then it only costs me $100 for a set of coils. Those could be trimmed shorter later, so the investment risked is really just a tank of gas.
I'm thinking I will cut some 1/4-inch mild steel to tack weld to the bottom of the transmission pan, likewise the engine oil pan.
See the USA in my Chevrolet? I'm game.
First up: Golden Spike to Lucin by dirt, where the old railroad tracks aren't, then another dirt road to Wendover, then paved down to Gold Hill, then dirt nearly all the way to the north end of Utah lake. That's along the old Pony Express, and there's geodes.
252 miles of off-pavement.
I may be a few months getting going, but I'll go get pics.

 

ha, that's awesome.

Have you stiffened the body any? (subframe connectors or anything like that?) I would think that would help, you don't want to tweak the frame climbing a bank or something, especially with it being a t-top car.

Also, i'd invest in a good portable air compressor and deep cycle battery.

Some people might frown at this, but it seems like a fun idea, enjoy it.

 

Yep, dual SFCs, inners and outers, plus an Optima red top. Just ordered the Ford Racing rebuild kit for the Traction-Lock differential in the '01 Mustang GT 8.8" rear axle I got for this car.

 

If anyone ever tries this, myself included, it seems to me that puncture resistance is more important than traction, that's what come-alongs ( hand winches ) and Hi-Lift jacks are for. The Jeep guys are all about airing down for traction, but are quick to point out it doesn't work with 10-ply tires. Fine. Better to not be stranded with a cut tire, even if it means more manual labor to get moving again. So run your 10-ply tires at 25 psi, not 80 psi, but also not 5 psi. 5 psi is what Jeepers air down to.
In that vein, I've found a 10-ply LT235/75R15E all-terrain that'd be good for the front, it's a Nokian Rotiiva A/T, rated to 111 MPH (speed rating S) Nokian item number T428439, I found them for under $150 ea, delivered.
And if I ever try this, I'll be trying something even larger under the rear. Partly because the rear doesn't steer, partly because the front isn't powered, and partly because it's easier when you can pick your line for the front without having to worry about where the rears go, which also helps justify swapping an overkill axle under the rear.
At trail speeds, big brakes are no help, and to protect the tire sidewalls from cuts ( sidewalls aren't 10-ply ) you want the narrowest wheel possible for your tire size, so a 7" is really not good for a 235/75, you'd do better if you can get 6s from a Monte or Astro, and better to run steel than aluminum, steel bends where aluminum breaks.

 

I got a '95 Jeep Cherokee 2-door 4x4 with the 4.0L, but I'm gonna put 35s under it. It came on a set of Cooper 235/75R15s, I still have this car and these wheels. The step-son that came with my marriage 4 months ago, he showed a little interest in my 'maros, but it turns out he prefers a second-gen Mitsu Eclipse. Anyway, a few days ago I saw the following pics from back in the '80s, dunno who to give credit to.

 

Hm, I've seen those pics before, don't know who's car that is though.


If you need any information/advice/etc on that XJ just PM me. I had a 96 XJ sport with the 4.0 liter that I drove for FOREVER, 260xxx miles before I sold it (still running like new). Now I'm in a 2000 grand Cherokee (WJ) with the same drivetrain. Love that engine, it's a SHAME that Jeep discontinued it.


One piece of advice - go ahead and buy a complete poly bushing kit, it'll run you a couple hundred bucks but you'll never have to deal with the dreaded "death wobble" after you lift it.


To avoid the possibility of getting this thread closed for going on a Jeep tangent I'll end there lol.

 

Thanks, I'm glad someone is following this one.
I don't want to hurt a third-gen, especially not until I get a '91-'92 'bird, but my '86 sport coupe isn't anything special.
My Jeep is for just in case Barack Odumba refuses to step down.
Meanwhile, I figured out some taller springs for this, I'll try to post that info tonight.
I'm leaning toward starting with 245/75R16s on stock 16x8s on the stock axle, while finding a Ford 9" so I can run 2.47:1 gears on the road, and 7.33:1 gears off-road.
I have a 4.8L LSx V8 and a 2WD version of the SM465 I can install.

 

Yup, still here lol. Nice, sounds promising!

 

I already have the 16x8" wheels, I already have a pair of 245/75R16s, and I have the 245s on another pair of 8s, it isn't right, but it could be street-driven.
I'm not a fan of aluminum wheels off-road, because cast aluminum breaks where steel only bends. I could try 265/70R16s, but Summit Racing has a good deal on 265/75R15s. I didn't know this size existed, but they're 30.7" dia.and $115 each, shipped. And they'll fit on my stock steel 15x7s.
Matching fronts in 235/75 for $100 each, shipped, I think this is what I'll try for.
When I get a 9", Jeep steelies are 5x4.5" and 15x7, or some Ranger Splash wheels were steel 15x7, 5x4.5".
For lift springs, the rears have fewer options, I'm thinking I'll cut the pigtails off one end of Moog CC845s. Up front, there are too many choices. Moog 5556 may get tried first.
The SM465is heavy, unbreakable, and hangs too low, plus the shifter tower is too tall and way too far forward, but that 6.55:1 first gear is great for crawling, probably more out of washes than over rocks, but I have the trans, the shifter, the clutch, the flywheel, the starter, and all the bolts. It doesn't take a slip-yoke, it has a fixed yoke for a 1350 joint.
But the 700R-4 /4L60E has OD, it doesn't hang so low, it has a 3.06:1 low, and some aftermarket torque converters can be an effective 2.55:1, so I may try to sell the SM465 for what Pick-N-Pull charges.
Slightly off-topic? If so, please, MODERATORS, don't delete, because it is relevant to getting the most from trying to fit these tires.

 

Our rear wheelwells won't quite fit a 31.00" tire, but I'm willing to get very close. Those Firestones are snow tires. I checked DiscountTireDirect.com, They have Nankang 31x10.50R15s for $115 delivered, I checked Nankang's website for the specs. They have your choice of A/Ts or M/Ts at that price, both are listed as being 30.50".
Undecided about wanting matching fronts. From behind, A/Ts might pass for snow tires, M/Ts would be advertising what I'm up to.
The M/Ts have matching fronts for $ 87 ea, delivered, 235/75R15, but I can't see any benefit. I'll be going slow like the white car in the vid above, not fast like the race car in the pics above.
Up front, it's probably these: http://www.discounttiredirect.com/di...5&rd=15&cs=235
Or maybe some A/Ts: http://www.discounttiredirect.com/direct
Rear A/Ts: http://www.discounttiredirect.com/di...50&rd=15&cs=31
Rear M/Ts: http://www.discounttiredirect.com/di...50&rd=15&cs=31
No, I don't work for DTD. They just have great prices.
Oh, and F9 7.33:1 gears are $303, D60 7.17:1 gears are $320, F8.8 5.71:1 gears are $210, F9 7.00:1 gears are $200, and GM 7.625" 4.56:1 gears are $145.

 

I like the tread on the M/Ts. Have you looked into Goodyear Wrangler Authority A/Ts? They are VERY aggressive, and look similar to the M/Ts you posted but are A/Ts somehow. I'm not sure if they come in a 235 though. . . . I'll have to keep those M/Ts in mind when it comes time for new tires on my Jeep!

 

Cool, thanks!
I have experience with a 350 / 700R4 / 3.73:1 / 26" combo in another third gen, and that's my most relevant reference for trying to gear this. I did a few spreadsheets, and it looks like I want to start with some 4.30:1 gears, partly because Isuzu used that ratio in the GM 7.5" axle under their early-'90s P'up, so finding them used in the salvage yard for $35 is realistic. The SM465 / 2.47:1 looked decent, but not the SM465 / 7.00:1 nor even a SM465 / 4.56:1, so I'll probably sell the 4.8 and SM465 to get a 350 / 700R-4.

 

How are you planning to do suspension travel on the rear? Pretty stiff or stock or. . .?


Just thinking about tire size, you don't want to a) chew up your fender or (worse) b) chew up your tires. . .since they aren't cheap!

 

It seems to me that I want to keep the car up as much as practical, partly because of the long front overhang. The limiting factor in the rear is the shocks, longer shocks will need to pass through the floorpan. I have seen interior shock towers for Cherokees, so with that I could have more droop.
I have the Moog coil spring catalog, but I find no longer rear springs that are higher rate also. But cutting coils stiffens springs. With pigtails on both ends, one end must be cut, but that's fine, I'm not sure 5" of extra rear ride height would work.
I'm thinking nylon travel-limiter straps at all 4 corners.
I'm thinking there's not much practical increase possible for the front suspension travel, so just the slightly longer coils to keep it as high as "stock" struts allow. Also saves having to mess with the steering, aside from maybe a bumpsteer kit.
For dirt roads, I see no need for a big brake upgrade.
With an overkill rear axle and taller tires on the rear, I just have to pick a line that works for the front, let the rear go wherever it goes. Not sure what I want for a differential, but not a spool, not an open, and probably not a limited slip like an Auburn. I could probably use a Gov-Lock without breaking it, but even when it's "locked", it's still just a limited slip. I'm not prepared to spend for a TrueTrac, I might try a LockRight, I might try a used Zexel Torsen.
The first step will be selling my 4.8 / SM465, I placed ads, then getting some tires. I think I can get a bald 31x10.50 for a test-fit, so I can buy springs right away. The 350 can wait, so can the 700R-4, I'll start hunting the 4.30:1 gears and the Zexel.
I have an Explorer 8.8, but I'm planning on swapping that under my Cherokee. I had another 8.8 from an '01 Mustang GT convertible, but I sold that when I was out of work. It's the correct width, within 0.4" per side, but only 28-spline.

 

I did a lot of trail running/camping all over the west one summer in a low mile stock 1993 Pontiac Sunbird I picked up for $600 that I cut the rear seat out and made a bed.. Just straddle berms, rocks, and don't be afraid to back out for miles if need be when the trail becomes unpassable.. Worse thing that happened to me was I ripped the muffler off, used the tin can and hose clamp method until I found a small shop to weld it back on for $35.. Not sure if i would do it in my camaro, only cause the height, width, and length of the vehicle and the trails I was attempting were pretty out there.. If you could build it like the pre-runner used in baja, then yes, but i just wanted to go, and not think much about it..

My best investment for this trip - A Camp Shower - made me feel good at the end of the dusty day.. http://www.ebay.com/sch/campshowers/...1&_from=&_ipg=

 

You MIGHT be able to get by with stock springs and just installing some "hockey puck" spacers to get between 1 and 2" of lift, it'd also be cheaper. That leaves you with the stock springs though so there's that.


What makes you want the Explorer 8.8? (just curious). My old Cherokee had the Chrysler 8.25 from the factory, which is the same axle they put under half ton RAM trucks for a while. My Grand Cherokee has a D35, which is alright so far (the 3.73's are fun, haha).


Depending on how much cutting/modifying you are willing to do, you might be able to shave some off the bottom of the nose and help your approach/departure angles without hurting the overall look of the rig. instead of just having a flat bottom you cut it diagonally from the front wheel to the end of the nose (lowest point being just in front of the wheel).

 

Just not having the ground effects helps the approach angle some. I'd rather change springs than try spacers.
The Explorer 8.8 uses 3.25" tubes, which means it takes the bigger outer bearings like the F150. The Chrysler 8.25 tubes are swedged down to take S-10 sized outer bearings.
If I pile all my family in my Jeep, that's over 1900#, plus 4 dogs, jerry cans of extra gas, all our 72-hour duffel bags, some jugs of water, ( gotta do a roof rack ) and it begins to get heavy.
The 7.5" axle is known for failing, I had a stock LO3 / 700R-4 / 2.73:1 break one just rolling up to a red light once. And that was the 7.625" 28-spline version, on 235/55R16 street tires, with nothing in the car but me and a half tank of gas. The 8.8 is known for it's strength, some guys are pushing 1500 HP through them, at street weight, so over 3000#.
I don't have a Chrysler 8.25", I considered the Dana 44, but I have the Explorer axle. I have a pile of 8.8 parts, and there's an 8.8 under the E150 van I drive every day.
I figure it better to try the $35 4.30:1 gear in the 7.5" before investing $200 in 4.30:1 gears for an 8.8 or 4.33:1 for a 9",
I already rolled the lips of the wheelwells when I thought I'd be trying 305/30R19s up front and 325/30R19s rear. I even bought a pair of 19" wheels for test-fitting.
Anyway, I'm regretting welding the ball-mount into the hitch, I could plug a winch mount into it otherwise, but I may weld up a hitch mount onto the ball-mount. Surely worth a $300 winch to be able to get home without an unplanned overnighter.

 

That's true. Cool cool, that all makes sense. Sounds like two pretty awesome builds!

 

Been comparing strut specs, even considered Mustang struts. Of the struts that are supposed to fit, and have specs online, I found differences in range of travel, and my choice is Monroe 71728 for $40 each, they spec at 7.125". That should be the range of travel for the front wheels. Seems to me a generous figure for a road car. Rears tomorrow.

 

Seems 31 people have viewed this since last night, I'm glad, but I wish more of you would comment.
With valvesprings, they list the coil bind height, or stack height, so I'm wondering if any of these Moog springs would be stacked before getting to the bumpstops? I can't find any way of knowing except buy and try, but I found Moog 9012 to be a more appealing choice for the front, even if they do cost half again as much. But right now I'm not buying either. Maybe a month from now I'll have enough on my credit card to order some.
If I am going to poke shocks through the floorpan on purpose, then that gives me freedom in the upper end of the rear shocks. The bottom end hangs lower than I'd like, so changing the shock mounts on the axle will give me more freedom there too, so then it is just finding some that match the springs. Can't predict that yet, but I'm not happy with the idea of the CC845s, so I'll be working on that.
I know everyone wants to see pics, but I probably won't have any for another month.

 

Now I've had my cola, I realize there is one indicator. If 2 springs have the same diameter, same free length, same wire size, but different spring rates, the higher-rate one will have fewer turns, so a shorter stack height.
Our stock rear springs, Moog 5665 or Moog CC635, are around 100 pounds per inch. I've been trying some 300s in the rear of my '94 Camaro, which is the exact same rear suspension as my '86, and a 300 appeals more for off-road.
But when I've been changing rear springs, I never evaluated the upper pockets for how well a smaller coil would sit. Our stockers are 4.30" I.D., most of the interesting choices from Moog are closer to 4.04".
I'll be checking AFCO's offerings before deciding.

 

Maybe I should ask the MODERATORS to move this to suspension?

 

Yup. I think poking your rear mounts through the floor is a good idea, considering your end goal. Because you don't need so much UP travel as the ability for the tire to travel DOWN. So the more shock length you can safely accommodate the better off you'll be there.

 

AFCO has some 275#/in rears, but 8" too short. I've seen how coil springs are made, there's no reason they couldn't just cut them at 20" instead of 12", but AFCO refuses. So much for their claims of doing custom springs. I'm now leaning toward Moog 8302 for the rear, if I can make them fit.

 

continuing this here: https://www.thirdgen.org/forums/memb...ja-camaro.html

 

Thanks, Cosmick, I'll be sure to follow!!