Version 3.0.... Making This One Last

[MrShoeBoy]

Calling Crash, Goatman, FarmerMatt, vetteboy, ashman, and others who have done extensive modification to keep the unibody alive....

In the last year or so I have been having problems with my current XJ. The doors are not lining up right, the tailgate doesnt open smoothly, a tail light was cracked from the tailgate/body flexing, theres a serious leak in the rear cargo area at the corners from cracks, the rear shackle boxes are starting to crack and tear as well, and the whole thing just feels "loose" and squeaky.

I first started out with a '89 Cherokee with a 3" lift with 31s and rolled it. No big deal, just swap everything into a "new" shell and move on. Well I did that about 6 years ago now and this current shell is about to die. I should have put a cage in it way back when but I did not have the tools, skills, or money at the time to do a cage. At this point in life, I have the tools, money (maybe), and the skills to do a full on build.

Over the years I have been watching various build ups and have a few questions for people who have built cages and done the reinforcing thing before...Goatman, vetteboy, ashman, Crash, plus any others I have forgotten.

Question #1 How much material really NEEDS to be added to the "frame rails" to A) keep them in shape and protect against rock damage, and B) provide enough stiffness to keep from tweaking the unibody shell, and C) to provide enough support for suspension links?

I have seen builds where people throw on 1/4" angle iron or box tube, but really what needs to be there to hold shape and not be complete over kill? I want a good strength to weight balance.

Question #2 Out of all of those who have done a cage, A) what is the best way to tie it in, B) How has this worked out since being built, and C) What do you like and dislike or would do over again having done it?

Most of the cages I have seen just put big flat plates on the floor and weld them in, then others bolt and or weld the plate down with another plate on the floor, then my favorite is the cage that goes through the floor and ties into the rock rails and beefed up frame rails.

Question #3 Did all the effort of trying to strengthen the unibody work out as planned? What would you do differently after having done it once already?

Question #4 I know the answer to this question will vary extensively between every build and location but just a ballpark # is fine. How much did you spend approximately to get the shell up to par? Lets talk about materials alone and not factor in labor just yet.

What I would like to build is a XJ with a 4.6L stroker, 5 speed manual, NP 231 really want an atlas or stak 3sp, HP Dana 44 front, Ford 8.8 rear, ~5" lift with 3 link front, 4 link rear 1/4 elliptical, 35s or 36" Iroks, flat belly or close to it, full interior cage with 5pt harnesses and race seats, and small exo similar Goatman's. I already have the drive train, just lack a good shell, a cage, seats and harness. The goal is to build something solid that I can take just about anywhere my nerves will let me and then drive it home Most of the wheeling I do is east coast rocks but I could eventually end up out west.

Thanks,

AARON

 

[vetteboy]

Hmm...well, first, I'm honored that you've included me in the ranks of such infamous people. I still bow to those guys for inspiration for sure, and I've certainly taken a good deal of info and applied it to my own thing.

I can't offer much yet because I don't have any longevity to my build. I wheeled it for a bunch of years with just 33's and "stock"ish suspension and didn't have any problems. Then I started breaking too much stuff so I set out on my current build. So here's my answers to your questions, based on my personal experience and also what I've tried to avoid:

Question #1 How much material really NEEDS to be added to the "frame rails" to A) keep them in shape and protect against rock damage, and B) provide enough stiffness to keep from tweaking the unibody shell, and C) to provide enough support for suspension links?

I would absolutely describe what I've done as overkill. No question there. Everyone looks at my build pictures and probably 60% of the time, the first question I get is, "how much does that thing weigh?"

I'll have a good answer as soon as I can drive it to my buddy's landscaping scale, but for now, I'll offer the opinion that it might still be within the GVWR rating of a stock XJ, as long as the gas tank is empty and there is no one sitting in it.

Partially it's the fault of the horror stories I've heard, and the fact that I don't want to have to "maintain" the unibody as it is. Even with everything I've done so far, I know I'll have to address the firewall/cowl/a-pillar area before too long, as I haven't yet. I want to get the drivetrain tested and solid on a few good runs, I want to make sure I don't have to make any major revisions to anything, and then I'll finalize the front.

Question #2 Out of all of those who have done a cage, A) what is the best way to tie it in, B) How has this worked out since being built, and C) What do you like and dislike or would do over again having done it?

I did plates on the interior, and matching plates below the floor that are tied into all the unibody reinforcement. Here's the A- and B-pillar plates, integrated into the rocker support and "boatsides":

the C-pillar tie-in:

and the D-pillar/rear tie-in:

As you can see, the 3x3 extends all the way back, where it's further integrated into the bumper mounts, rearmost cage support, and vertical tailgate support (for the MJ tailgate I put on there).

In retrospect...I'd probably try and find a more efficient way to do it, because at this point the cage probably wouldn't come out in one piece if I unbolted everything anyway. We'll see how it holds up, should be fine, but it's a lot of bolts and a lot more work to make all the matching footplates.

Question 3, like I said...this is a "brand new" build, so we'll see what happens.

Question #4 I know the answer to this question will vary extensively between every build and location but just a ballpark # is fine. How much did you spend approximately to get the shell up to par? Lets talk about materials alone and not factor in labor just yet.

I would estimate 20-30 feet of 3x3 angle, 150 feet of 1.75" x .120 DOM for the cage, and the rest has just been scrap metal I've found laying around and cut down to size. Prices will vary by region but I got the DOM tube for $3.05/ft and the angle was incredibly cheap as I got it surplus from a job a friend of mine was running.

What I would like to build is a XJ with a 4.6L stroker, 5 speed manual, NP 231 really want an atlas or stak 3sp, HP Dana 44 front, Ford 8.8 rear, ~5" lift with 3 link front, 4 link rear 1/4 elliptical, 35s or 36" Iroks, flat belly or close to it, full interior cage with 5pt harnesses and race seats, and small exo similar Goatman's. I already have the drive train, just lack a good shell, a cage, seats and harness. The goal is to build something solid that I can take just about anywhere my nerves will let me and then drive it home Most of the wheeling I do is east coast rocks but I could eventually end up out west.

Almost exactly my goals as well, except I just went a little larger. My motor has 170k flawless miles on it and I couldn't see adding any more expense and time to this build to replace it. Once it goes I'll be building a propane-powered 4.6 stroker. I've got a trip planned towards the end of May to go spend a long weekend up in New England and run a bunch of different trails and camp there, and right now my goal is to be able to drive the XJ up there (around 300 miles each way), wheel the whole time, and drive it home. Having to bring a trailer and tow rig would be annoying and a lot of the trails require driving on public roads for access. Next weekend (the 21st) is going to be the big shakedown run for mine so I'm sure I'll have some stuff to add after that...but as of now, I'm pretty optimistic that this rig will be able to do whatever I ask it to.

 

[Shadowgames96XJ]

I had my 8pt cage tied into the unibody frame, I had plates at the bottom of each pillar and than had a friend (the welder/master fabricator, since I have no welder/shop) and I made plates for the underside, and than tied those and the rock rails into the frame after it had been plated, with 3x3x1/4 angle, I was starting to lose my front leaf spring mounts, we add gussets everywhere possible, I still need to tie the rear most pillar in, I have my radius arms on my frame rails. it really stiffened things up, The first run out was great, I had the suspension doing the work instead of the unibody twisting. pretty much the cage is tied into the unibody, and the rock rails, are tied into the cage, and unibody frame, I don't know how much my jeep weighs, but would like to find out.

 

[Goatman]

Question #1 How much material really NEEDS to be added to the "frame rails" to A) keep them in shape and protect against rock damage, and B) provide enough stiffness to keep from tweaking the unibody shell, and C) to provide enough support for suspension links?

Question #2 Out of all of those who have done a cage, A) what is the best way to tie it in, B) How has this worked out since being built, and C) What do you like and dislike or would do over again having done it?

Question #3 Did all the effort of trying to strengthen the unibody work out as planned? What would you do differently after having done it once already?

Question #4 I know the answer to this question will vary extensively between every build and location but just a ballpark # is fine. How much did you spend approximately to get the shell up to par? Lets talk about materials alone and not factor in labor just yet.

AARON

#1. A 2" strap along the bottom of the frame will keep it from caving in. Anything more than that would be designed to add rigidity. Remember, structure, like triangulation, does more for rigidity than thick steel. I think that anyway you tie the LCA mount and the front leaf spring hanger together is going to help, like the T&J stiffeners, and I like the TnT stiffeners. I'd go for more boxing and less metal thickness. I did something totally different, but it seems to be working since mine is pretty stiff now.......though the cage helps, too. I put 1x3 boxed tubing down the side of the frame, spaced out from the frame by one thickness of the 1x3 on each end, the idea being that the structure created by the spacing would add more stiffness than simply covering the existing frame with more metal. If I had to do it again, I'd run round tubing down the side, attached to the spring hanger and then angled in to the frame ahead of the LCA mount.....with a 2" strap along the bottom of the frame to keep it from caving in.

#2. Cage tie ins should be a good as you can make them, within reason. The C and D pillars are easy since you can go right to the frame, but the A and B take more thought. On mine, the B pillar is tied into the shoulder harness bolt, so I only have a plate on the bottom bolted to the floor. The A pillar should eventually go to the frame if on the inside, or to the firewall if it goes behind the dash. I always try to get people to remember that the XJ body does a decent job all by itself, so there's no need to go hog wild on steel thickness and numerous tubes and braces.

I think the thing I like best about my cage, and it has worked well since I've rolled it 360* since the cage was built, is the way the A pillars are made. Mine is a partial exo with the A pillars going down through the top of the fender, tied into the side of the cowl, then to the leading edge of the rock rails. I have aminimal interior cage and a kind of minimal exo, and I like the combination. The inner cage is mostly to add rigidity, and is tied into the inside of the A, B, and C pillars. I also really like that my cage runs all the way to the front bumper, which I think is important for overall rigidity.

#3. Yes, mine is rigid. But, I've had more cracks even after doing the frame stiffeners and cage in the forward section. If I did it again, I would use the TemperMental forward frame reinforcement plates, and the SBS, and frame stiffeners along the sides, and a cage. I've done mine piece meal, and it would be much better to do it all at once. After the initial cracking, repairs, and building the cage, what I didn't reinforce enough was around the track bar frame mount and steering box, where there is a lot of flexing. Also, I've had cracks in both the front and rear crossmembers. Do it all at once.

#4. I have no idea. I don't keep track. Since I didn't buy anything premade, the cost of mine is the cost of the scrap metal and my labor, plus the cost of the tubing for the cage. There are good products out there now, and if I was doing it again I would use them.

I don't know that I start over on another shell. I considered it, but when I made a list of everything I would have to move or redo, and added up the hours to do it, it was way more than I wanted to do. So, mine is the same rig I've been wheeling hard for 13 years, and the cracks are repaired. It's stiff enough now that there's nothing further to worry about. You can look over some Jeepspeed rigs to get ideas on how to beef things up, those guys have come up with many good ideas.

 

[MrShoeBoy]

Thanks vetteboy, after your next trip out post up an update! You better have pictures I followed most of your build thread and like all the tie in points.

Shadowgames got any pics of the additional bracing? I would love to see how everything attaches to everything else.

Thanks goatman, that was exactly what I was looking for. Got any pictures of the box tube you added for the frame rails? I have an idea what you are talking about but pics would help. I have thought about beefing my existing body but there is a lot of suspension things I want to change up front and I think it would be easier to build from scratch, plus the doors physically dont line up and theres excessive warping going on in the rear upper quarter panels.

AARON

 

[Goatman]

Well, here's a pic of what I did. I think it helped, but if I did it again I'd do it differently. I'd use round tubing instead of boxed and carry it forward of the LCA mount, and attach it in the back directly to the front spring hanger.

 

[Ty2003K]

Goatman

Why would you use round tubing if you did it again? Seems like the square or rectangle would work better as you did it.

 

[MrShoeBoy]

Goatman

Why would you use round tubing if you did it again? Seems like the square or rectangle would work better as you did it.

Typically round tubing has better torsional stiffness than square or rectangle when comparing similar size material. The bracing he did goes from the control arms up front to the front leaf spring mount in the rear, so when the suspension is cycling, its trying to twist the body so thats the main reason why round would be better in that application.

I did some more searching over on the JeepSpeed forum as well as on this forum and have a general plan on what I want to build. Thanks for the help guys!

AARON

 

[Goatman]

Goatman

Why would you use round tubing if you did it again? Seems like the square or rectangle would work better as you did it.

Yeah, what he said. I'd run a 2" strap down the bottom of the frame to protect it, then some 1.75" or 2" tube down the side of the frame for rigidity. The round tube has more stiffness/rigidity than rectangular tubing.

 

[MrShoeBoy]

Anybody else have thoughts or opinions? I know there are several people out there who have gone through and done all the frame plating and cage install to prevent the unibody from folding like a taco.

AARON

 

[BIGWOODY]

Anybody else have thoughts or opinions? I know there are several people out there who have gone through and done all the frame plating and cage install to prevent the unibody from folding like a taco.

AARON

scrap it and build a chassis....:wave:

 

[Weasel]

clean everything off the underside and weld all of the seams.

One thing that might cause you problems is something Goatman mentioned, if you stiffen up the chassis too much you might get even more cracking as the body is not flexing and the stress is going to be localized in the none stiff areas rather then be taken up through the entire chassis.

 

[MrShoeBoy]

scrap it and build a chassis....:wave:

Can I have yours? Or do you want to buy me a tow rig and trailer Let me know if you find anything deceint up in the Gboro area. I still gotta be able to drive this thing in snowy winter weather. I am moving to Cincinnati in September and want a roof and heat

AARON

 

[XJEEPER]

Richard's experiences as well as many others who have pushed the limits of the unibody enspired me to beef this rig up before it ever hits the trail, no guarantees of course........SBS/TMR/T&T plated front to back. Armor is next.

 

[MrShoeBoy]

XJeeper, got any more pics of what you have installed/ done? I would like to see the fit and finish of these parts. Plus I would like to see how it all fits together. I keep debating if its worth the money to buy the parts or fabricate them.

AARON

 

[XJEEPER]

Which parts? Here's the fit of the TMR plates, which are available in 1/8" and 3/16", your choice.....I went with 1/8". Fit is perfect, well engineered component and easily trimmed to match up to the JKS SBS and T&T stiffeners.

As for the T&T truss, another well engineered component and well worth the money. Just chop of the stock UCA mounts, drop the truss in place, square up at the spring perches and stitch weld in place.

Sorry, not trying a hijack....... should be relevent info for this thread.

 

[MrShoeBoy]

Thanks for the pics! Pics like these are EXACTLY what I was looking for. I was kinda hoping for some more feedback from people who have already done this and have had it out on the trail, but build up pics work just as well.

AARON