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kmas0n

kmas0n

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Also, ordered so Nitto Trail grapplers today... 40x13.5R17.
After lots of careful measuring, there is room, with maybe a little rubbing on the fenders in extreme situations.
 
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Trevlaw

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The rough draft of the shock tower is together... this is actually version 3.0. One thing to note... 2.5's max out what the poly towers are capable of. There is VERY little wiggle room. I had hoped to cant the towers back at the same angle as the rear (for my OCD), but there isn't enough room for the shock to swing front to back unless they are closer to vertical. So they are nearly upright (85*). I put the steering shaft back in to make sure there is no interference.

full compression.
View attachment 347297


Nearly full extension. I need some taller jack stands. The castle bolt is laying on the floor at 12" of droop... so, its going to need a lot taller. Currently its going to work out 5 up 9 down front and 6 up 8 down rear. I may increase ride height another inch for 6up 8 down/ 7up 7down. According to the internet, its better to have slightly more up travel in the rear, so this is perfect.

I may also have to lean the towers out a few more degrees. At full flex the springs are going to contact the frame. currently they are about 3*
I did a quick cycle with a tire on and it doesn't get anywhere near the shock at this config, so there is room to move.

View attachment 347298

Full compression from the side. The shock is biased towards the front of the tower at full compression. Neutral at ride height. How neutral? at ride height I can easily slide the bolts out of the shock ends.

View attachment 347299

Potential hydro bump location. I like that I can tie the trackbar, bump stop cup, and shock tower together.

View attachment 347300

Interesting. The 2.5 foxes come with a different rod end (com 10?) that looks like a rubber bushing with a 1.5 width, so no goofy spacers needed. Clearance is tight here. I had to drill a large hole in the bottom of the shock mount to clearance the shock end.

View attachment 347301

Resisting the urge to weld all the things. Still a few things to check, tweak, and nudge. I think the front has been easier to fabricate than the rear.

What rubber bushing are you talking about in the lower eye? Should be a Com10 bearing with two metal spacers that go into the bearing. Maybe you got the new style spacers with O rings on them?

Looking good, You're gonna like the 2.5s. I'd raise it the inch for 7/7" split in the rear. I've got 8" up in the rear and 6.5" in the front and it gets after it as much as the tractor motor can push it
 
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kmas0n

kmas0n

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What rubber bushing are you talking about in the lower eye? Should be a Com10 bearing with two metal spacers that go into the bearing. Maybe you got the new style spacers with O rings on them?

Looking good, You're gonna like the 2.5s. I'd raise it the inch for 7/7" split in the rear. I've got 8" up in the rear and 6.5" in the front and it gets after it as much as the tractor motor can push it

I'll get a closer look tomorrow.

I'm looking forward to the 2.5's for the TJ. After I've spent some time on the front, I'm going to see how viable they are to adapt to the rear. Every forum post I could find pretty much agreed... everyone who did 2.0's wishes they had done 2.5's
 

Trevlaw

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I'll get a closer look tomorrow.

I'm looking forward to the 2.5's for the TJ. After I've spent some time on the front, I'm going to see how viable they are to adapt to the rear. Every forum post I could find pretty much agreed... everyone who did 2.0's wishes they had done 2.5's

I don't remember the compressed lengths off the top of my head, but if your rear is setup for 14" 2.0s, some 12" 2.5s might nearly bolt in length wise, and should have a 1" spacer inside between the piston and bearing block you can pull out to make them 13's. Plus there's some stubbier lower eyes you can get for the 2.5s too I believe, about an inch shorter maybe.
 
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NashvilleTJ

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The rough draft of the shock tower is together... this is actually version 3.0. One thing to note... 2.5's max out what the poly towers are capable of. There is VERY little wiggle room. I had hoped to cant the towers back at the same angle as the rear (for my OCD), but there isn't enough room for the shock to swing front to back unless they are closer to vertical. So they are nearly upright (85*). I put the steering shaft back in to make sure there is no interference.

full compression.
View attachment 347297


Nearly full extension. I need some taller jack stands. The castle bolt is laying on the floor at 12" of droop... so, its going to need a lot taller. Currently its going to work out 5 up 9 down front and 6 up 8 down rear. I may increase ride height another inch for 6up 8 down/ 7up 7down. According to the internet, its better to have slightly more up travel in the rear, so this is perfect.

I may also have to lean the towers out a few more degrees. At full flex the springs are going to contact the frame. currently they are about 3*
I did a quick cycle with a tire on and it doesn't get anywhere near the shock at this config, so there is room to move.

View attachment 347298

Full compression from the side. The shock is biased towards the front of the tower at full compression. Neutral at ride height. How neutral? at ride height I can easily slide the bolts out of the shock ends.

View attachment 347299

Potential hydro bump location. I like that I can tie the trackbar, bump stop cup, and shock tower together.

View attachment 347300

Interesting. The 2.5 foxes come with a different rod end (com 10?) that looks like a rubber bushing with a 1.5 width, so no goofy spacers needed. Clearance is tight here. I had to drill a large hole in the bottom of the shock mount to clearance the shock end.

View attachment 347301

Resisting the urge to weld all the things. Still a few things to check, tweak, and nudge. I think the front has been easier to fabricate than the rear.

Have you checked the clearance for the springs? A trick I used while doing the setup was to leave the center spring follower in place. On my shocks it’s the same outside diameter as the springs. Slide it up and down during cycling and you know your spring clearance.
 
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kmas0n

kmas0n

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What rubber bushing are you talking about in the lower eye? Should be a Com10 bearing with two metal spacers that go into the bearing. Maybe you got the new style spacers with O rings on them?

Looking good, You're gonna like the 2.5s. I'd raise it the inch for 7/7" split in the rear. I've got 8" up in the rear and 6.5" in the front and it gets after it as much as the tractor motor can push it

I checked the shock ends this morning. You are correct, Com10 bearing with two spacers and a large o ring. Thanks
 
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kmas0n

kmas0n

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I don't remember the compressed lengths off the top of my head, but if your rear is setup for 14" 2.0s, some 12" 2.5s might nearly bolt in length wise, and should have a 1" spacer inside between the piston and bearing block you can pull out to make them 13's. Plus there's some stubbier lower eyes you can get for the 2.5s too I believe, about an inch shorter maybe.

I've considered 12" 2.5's as well. I really need to get the rear driveshaft so I know if it can even support 14" of travel. I didn't know the trick with removing the spacer worked on the 2.5's too. Good to know.
 
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kmas0n

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Have you checked the clearance for the springs? A trick I used while doing the setup was to leave the center spring follower in place. On my shocks it’s the same outside diameter as the springs. Slide it up and down during cycling and you know your spring clearance.

I've been sliding the spring over the shock to check clearance. Thanks for the tip!
 

Trevlaw

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I've considered 12" 2.5's as well. I really need to get the rear driveshaft so I know if it can even support 14" of travel. I didn't know the trick with removing the spacer worked on the 2.5's too. Good to know.

Yeah, the spacer trick is handy. Obviously the spacer is there for a reason, to keep the shaft from kind of wobbling or kicking to the side too much inside the body, but I've been running my 12"(13") 2.0 smooth bodies with the spacer removed for several years and haven't noticed any ill effects. I think it can also cause premature wear of the wiper seal in the end cap.

I'm not sure if it would be more or less of a problem with coilovers. I'd think if the springs never unseat at full droop that the preload from the springs would probably keep the shaft straight with the body near full extension moreso than just a smooth body shock
 
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kmas0n

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Yeah, the spacer trick is handy. Obviously the spacer is there for a reason, to keep the shaft from kind of wobbling or kicking to the side too much inside the body, but I've been running my 12"(13") 2.0 smooth bodies with the spacer removed for several years and haven't noticed any ill effects. I think it can also cause premature wear of the wiper seal in the end cap.

I'm not sure if it would be more or less of a problem with coilovers. I'd think if the springs never unseat at full droop that the preload from the springs would probably keep the shaft straight with the body near full extension moreso than just a smooth body shock

I suspect it offers support when the shock is most vulnerable at full extension. I also suspect the rear threat is bind at the Com8 or 10 bearing from axle rotation due to the nature of link suspension. Does the trick work on 14" coil overs... so 15"?
 

Trevlaw

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I suspect it offers support when the shock is most vulnerable at full extension. I also suspect the rear threat is bind at the Com8 or 10 bearing from axle rotation due to the nature of link suspension. Does the trick work on 14" coil overs... so 15"?

Yeah that is the main point of it I believe. The com bearings do get close to maxing out on my setup, but I was able to pull 14" out of my old 2.0s in the rear, so shouldn't be a big problem.

I think all the shocks have the spacer after a certain length, I was happy to find my 10" 2.5s had a 1" spacer. I can't remember for sure, but I think the 14's might have two one inch spacers in them
 
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kmas0n

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I'm confident about the placement of the trackbar and upper link mount, and I got tired of the tack welds breaking when cycling for the coil overs, so I welded the mounts up. I thought I would include a little detail about the upper link mount.

I cut the factory style upper mount in half, so there were two prongs sticking up and then fitted some tube for an internal structure.

PXL_20220801_154508676.jpg


Then I built the link mount from this foundation.

PXL_20220801_155744748.jpg


I was able to weld the 1/2 tube to the inside of the link tabs, as well as weld them to the housing. Usual treatments were performed, pre heat, post heat, blanket for slow cooldown.

Other side.

PXL_20220802_125028498.jpg


Top view.

PXL_20220802_125120886.jpg


I still wanted a little more support in between the tabs and the prongs, So I made this little bridge that tucks down inside and anchors everything together.

PXL_20220802_131606659.jpg



welded.

PXL_20220802_132959564.jpg


As mentioned a few pages back, the reason I didn't do the standard truss bridge is with the V8 there simply wasn't room for one without loosing significant up travel. So this is as strong of an upper mount as I know how to make. Gusseted internal structure, and a differential cover tie in. For a failure, I would have to hit something hard enough to rip the top of the pumpkin off.
 
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kmas0n

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Thoughts on front sway bars.

So, since designing my front steering and suspension, I noticed a few things.

When raising the axle side trackbar mount up, and therefor raising the roll axis with it, I researched side effects of having such a high roll center. From what I read, it creates a very stable platform. Its said the rig feels well planted in off camber and sidehill situations, but doesn't give much warning when it does tip. Also for street use because the axle has a mechanical advantage on the frame (longer lever) there is a lot less body roll, but increased side to side jostling when going over uneven bumps.

I can confirm this sensation a little... before the TJ went under the knife I had lowered the frame side rear trackbar mount 2 inches... which has the opposite effect. the Body had more leverage against the axle. Head toss or side to side jostling was reduced, but body roll was increased.

I've noticed a lot of very high end rigs (genright) that run a high roll center don't run with a front anti-rock. but They still have a rear sway bar. (4 links usually have a pretty low roll center).

Thoughts, experiences?
 

TRE3TOP

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Thoughts on front sway bars.

So, since designing my front steering and suspension, I noticed a few things.

When raising the axle side trackbar mount up, and therefor raising the roll axis with it, I researched side effects of having such a high roll center. From what I read, it creates a very stable platform. Its said the rig feels well planted in off camber and sidehill situations, but doesn't give much warning when it does tip. Also for street use because the axle has a mechanical advantage on the frame (longer lever) there is a lot less body roll, but increased side to side jostling when going over uneven bumps.

I can confirm this sensation a little... before the TJ went under the knife I had lowered the frame side rear trackbar mount 2 inches... which has the opposite effect. the Body had more leverage against the axle. Head toss or side to side jostling was reduced, but body roll was increased.

I've noticed a lot of very high end rigs (genright) that run a high roll center don't run with a front anti-rock. but They still have a rear sway bar. (4 links usually have a pretty low roll center).

Thoughts, experiences?

Only note I want to point out about the gen right rigs is the gen right rear sway bar is substantially stiffer than the anti rock rear.
 
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starkey480

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Thoughts on front sway bars.

So, since designing my front steering and suspension, I noticed a few things.

When raising the axle side trackbar mount up, and therefor raising the roll axis with it, I researched side effects of having such a high roll center. From what I read, it creates a very stable platform. Its said the rig feels well planted in off camber and sidehill situations, but doesn't give much warning when it does tip. Also for street use because the axle has a mechanical advantage on the frame (longer lever) there is a lot less body roll, but increased side to side jostling when going over uneven bumps.

I can confirm this sensation a little... before the TJ went under the knife I had lowered the frame side rear trackbar mount 2 inches... which has the opposite effect. the Body had more leverage against the axle. Head toss or side to side jostling was reduced, but body roll was increased.

I've noticed a lot of very high end rigs (genright) that run a high roll center don't run with a front anti-rock. but They still have a rear sway bar. (4 links usually have a pretty low roll center).

Thoughts, experiences?

Not an expert, but don’t front and rear sway bars work together to keep the rig balanced? I also thought they add balance to the front axle traction wise while articulating and help balance the rig between the two tires, but I don’t fully understand the dynamics yet.
 
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Mike_H

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Not an expert, but don’t front and rear sway bars work together to keep the rig balanced? I also thought they add balance to the front axle traction wise while articulating and help balance the rig between the two tires, but I don’t fully understand the dynamics yet.

What @kmas0n is saying is statically correct. Went raise the roll center toward the center of gravity, you essentially have a shorter lever therefore it takes MORE force to create the same displacement (think of a teeter-toter that is has a pivot point biased toward one end).

If you have a stiff enough front (or rear) bar, you can make the other unnecessary...the trade off is the lighter the anti-roll bar, the easier it is for the axle to articulate...enter the Anti-Rock, sway lock, etc. So, the trick is to balance the sway bars with all the other things (weight distribution, ride characteristics, etc). You want the lowest rate of sway bar possible to fit the design criteria (which is different depending on how you use your jeep) If you try to do it all on one axle, you violate that "light as possible" because you could split the rate between two axles instead of one.

Hope that makes sense...I'm at work and a little distracted...
 
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Trevlaw

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I'm no expert either, and haven't messed around at all with moving the track bar mounts around at all. I have been running the savvy mid arm with just a front anti rock on the loosest setting for the past several years though. I got used to the body roll and it never bothered me a whole lot, but having all of the roll resistance at just the front of the vehicle does feel a bit odd on hard corners. The rear is definitely more squirrely and I can feel myself tipping forward and to the side instead of just sideways, also makes the rear end more prone to sliding as there's not much down pressure on the inside wheel.

I'd imagine you'd feel similar effects, just the opposite with a rear bar and no front. If I had the option of either having all the roll resistance on the front or back, vs the same roll resistance split 50/50 I'd definitely go with the latter.

All anecdotal and probably not very helpful. Though I'm currently working on fitting a rear TJ antirock on, but not in the usual over the gas tank way. My clearance between shocks and tires is non existent so no way a sway bar arm and link was going to fit between them. The rear TJ antirock bar seems to be just long enough to stick out enough on each side between the rear frame rails under the rear body mounts, through that cross member. I'm eliminating my rear body lift pucks and putting the same length spacer on top of the cross member. The lower body mount will go up inside the tube spacer, with the upper mount on top of it. Then drilling, counterboring and tapping the sway bar arm for a 7/16-20 socket head bolt for rotational clearance in that outside corner of the cross member. Going to hole saw through both halves of the frame, weld in a metal sleeve on both sides that the bushings press into, then slide the bar through there. The arm should end up just inboard of my 2.5s and behind them enough where a long axle side tab can stick out towards the rear for a link. I'm also using front antirock arms just because I had an extra set.

Just another option if you are also tight on space, should have it done next week and I haven't found a reason why it shouldn't work yet.
 
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Trevlaw

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Here's a couple pics of what I'm working on. It'll be tight with the arm, but I think it should work. May need to cut and dog leg the arm for cross member clearance at full bump
PXL_20220804_192453318.jpg


PXL_20220804_192514589.jpg
 
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