The LBP XJ Cherokee POS

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Scott Cee AKA 2drx4
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Re: The LBP XJ Cherokee POS

Post by Scott Cee AKA 2drx4 »

Got those wires spliced back together with some dualshield splices. There was wires that were basically just twisted together under the tape, as somebody tried to solder them but failed miserably.

Also since I don't think I mentioned it, I'd installed a modded IC-2300H with a RAM mount for comms. Works really good for the price. And the RAM mount means it's easy to take out if I want to put it in another vehicle.
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Re: The LBP XJ Cherokee POS

Post by Scoobienorth »

I’ll say scrub radius matters. After my fiasco. I’m curious as to the difference though. For snow wheeling the beadlocks are nice but not as needed as people think unless you’re planning on rock crawling in the snow or slick conditions where you’re beating on things and sliding into stuff. We regularly run 2-5 psi and about the only lost beads were me doing things that had every right to, like winching sideways at 3 psi. Radials seem to hold their bead better than bias plies. If it were me I’d run what you got and see how it does and what you want to change then. The toyo’s never impressed me in the snow, my 33” claws left a set of 35’s on a 80 series behind by a long ways but I’d give them a shot. Maybe a couple 1/16” grooves in each center lug would help.

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Re: The LBP XJ Cherokee POS

Post by pointsnorth »

running the rims you have is making the best with the ackerman angle built into your front diff as it was engineered for a vehicle with significantly longer wheel base having put these into the cherokee the intercecting axis of your front wheels is closer to your rear bumper rather than being the center point of your rear axle that causes more pushing then following of the axle.

a little cut and paste
The intention of Ackermann geometry is to avoid the need for tyres to slip sideways when following the path around a curve.[2] The geometrical solution to this is for all wheels to have their axles arranged as radii of circles with a common centre point. As the rear wheels are fixed, this centre point must be on a line extended from the rear axle. Intersecting the axes of the front wheels on this line as well requires that the inside front wheel be turned, when steering, through a greater angle than the outside wheel

A simple approximation to perfect Ackermann steering geometry may be generated by moving the steering pivot points outward so as to lie on a line drawn between the steering kingpins and the centre of the rear axle in the case of a solid axle forward facing steering arm

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Scott Cee AKA 2drx4
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Re: The LBP XJ Cherokee POS

Post by Scott Cee AKA 2drx4 »

Scoobienorth wrote: Tue Nov 05, 2019 8:17 am I’ll say scrub radius matters. After my fiasco. I’m curious as to the difference though. For snow wheeling the beadlocks are nice but not as needed as people think unless you’re planning on rock crawling in the snow or slick conditions where you’re beating on things and sliding into stuff. We regularly run 2-5 psi and about the only lost beads were me doing things that had every right to, like winching sideways at 3 psi. Radials seem to hold their bead better than bias plies. If it were me I’d run what you got and see how it does and what you want to change then. The toyo’s never impressed me in the snow, my 33” claws left a set of 35’s on a 80 series behind by a long ways but I’d give them a shot. Maybe a couple 1/16” grooves in each center lug would help.
Yeah, I'm sure the scrub radius still matters, but I'm thinking it isn't as important. That's assuming I don't buy some 2" BS wheels and then weld a ring onto them, making the scrub radius extremely bad, as seems to be super common in the rest of the Jeep world. :laughing: There's a fair number of steel (ugh) wheels out there with 4-5" of BS (I'm assuming they're all 8" wide wheels because that's all I'd look at), along with some aluminum ones, but that's still 2"~ less than the factory wheels. I'll have to look around and see, as you said it doesn't matter as much if you have beadlocks as most people make out, it is apples to oranges running low PSI in snow compared with in other scenarios where there will always be more side loading on the tires, and if I use some Sitkaflex or roofing poly on them I think I can get them to hold to any pressure I'm likely to run. But I like buying shiny baubles so beadlocks would be cool. :lmao:
pointsnorth wrote: Tue Nov 05, 2019 8:42 am running the rims you have is making the best with the ackerman angle built into your front diff as it was engineered for a vehicle with significantly longer wheel base having put these into the cherokee the intercecting axis of your front wheels is closer to your rear bumper rather than being the center point of your rear axle that causes more pushing then following of the axle.

a little cut and paste
The intention of Ackermann geometry is to avoid the need for tyres to slip sideways when following the path around a curve.[2] The geometrical solution to this is for all wheels to have their axles arranged as radii of circles with a common centre point. As the rear wheels are fixed, this centre point must be on a line extended from the rear axle. Intersecting the axes of the front wheels on this line as well requires that the inside front wheel be turned, when steering, through a greater angle than the outside wheel

A simple approximation to perfect Ackermann steering geometry may be generated by moving the steering pivot points outward so as to lie on a line drawn between the steering kingpins and the centre of the rear axle in the case of a solid axle forward facing steering arm
The modified steering arms make the Ackermann even worse than it would be if I'd been able to run everything straight up how Dana made it, as I had to move the TRE holes inwards a bit. If I had gone to larger wheels (20s, yuck) I probably could have kept them where they were or even moved them out. That said it's way better than most people who run straight or inward offset high steer arms and have no Ackermann or reverse (anti-Ackermann?).

I think it's still a bit inconclusive how much it matters with the use of lockers, as when locked the inside front tire then always has the shortest path and the lockers mean it likely has to slip, since the other tires are probably not going to roll/freewheel faster than it, and if it's slipping in the forward direction it will likely just get pushed to where it 'needs' to be. But like I said, I think it's a bit inconclusive how much it matters, at least for low traction stuff.

In general it seems if you can get scrub radius and Ackermann mostly correct things will just work better... Which was part of the goal in the first place.

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Re: The LBP XJ Cherokee POS

Post by HillBilt »

What really is a "perfect" Ackermann or scrub radius in the offroad department? with steering angles now into the 50*. (Legit question-not being an ass)

Ive got a terrible scrub radius right now with running front wheel spacers, and honestly don't even notice it at all, like zero. Still waiting on one to come off and hit a bus of transgenders :rainbow:
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Re: The LBP XJ Cherokee POS

Post by Scott Cee AKA 2drx4 »

HillBilt wrote: Tue Nov 05, 2019 10:40 am What really is a "perfect" Ackermann or scrub radius in the offroad department? with steering angles now into the 50*. (Legit question-not being an ass)

Ive got a terrible scrub radius right now with running front wheel spacers, and honestly don't even notice it at all, like zero. Still waiting on one to come off and hit a bus of transgenders :rainbow:
Good point. Once the steering angle is extreme it's not like things aren't just binding or slipping anyways.

However I know this thing drives way better and steers way better than my old MJ, which would be fairly comparable as far as wheelbase and overall width went, but it used stock width axles and 3.5" BS wheels and had straight steering arms. I don't know how big of a difference it necessarily makes offroad, but it's essential for easily finding a parking space while going to an ice cream meet, and I need to be able to take a hand off the steering wheel so I can wave to the JLs. :lmao:

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Re: The LBP XJ Cherokee POS

Post by pointsnorth »

Ackerman and scrub are two different aspects of steering geometry but can both affect each other too a degree.
Image
This shows what a perfect Ackerman angle would look like. this example shows the tie rod behind the steering axle but flipping it forward a line drawn from the the tie rod to Center of kingpin will have both lines converging at rear axle.

Most axles are set too work most efficiently at a set wheel base

Ackerman is only considered at or for slower speeds as most high speed application use a reverse Ackerman designs


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Re: The LBP XJ Cherokee POS

Post by pointsnorth »

This comes into effect once turning as we know the two front tires are at different turning angles have the right angle minimizes the pushing thru from the rear axle

Ackerman is really some that is never considered in a standard wheel alignment in a stock vehicle but consider an axle like the super 60 in a ford it’s designed to work in its upper range 200 plus wheel base dropped into a Jeep tj wheel base that when consideration of Ackerman angles nee to be considered the most.


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Re: The LBP XJ Cherokee POS

Post by Scott Cee AKA 2drx4 »

pointsnorth wrote: Tue Nov 05, 2019 11:07 am Ackerman and scrub are two different aspects of steering geometry but can both affect each other too a degree.
Image
This shows what a perfect Ackerman angle would look like. this example shows the tie rod behind the steering axle but flipping it forward a line drawn from the the tie rod to Center of kingpin will have both lines converging at rear axle.

Most axles are set too work most efficiently at a set wheel base

Ackerman is only considered at or for slower speeds as most high speed application use a reverse Ackerman designs


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Even from the factory the Ford axles were a compromise. I forget where the center point of the Ackermann works out to on them, but it doesn't actually correspond with any of the wheelbases that they offered, it's just "somewhere back there." Obviously they were limited the same way I am, in the if you have the steering on the front side of the axle it means the TRE locations have to move outwards, and that interferes with the wheels. They also were offering a variety of wheelbases and didn't want to make a bunch of different axles. And I think it makes even less of a difference once the wheelbase is past a certain amount, likely a value that can be expressed by a multiple of the vehicles width.

I think scrub radius matters far more on high traction surfaces, as if it isn't right it will dramatically increase the required steering force, and it actually forces the tire to break traction when being turned with the vehicle stopped (one tire has to move back, one forwards, fine with an open diff but with a locker it means something has to give).

Also with Ackermann you're not getting full steering angle on one of the tires. In the event that only one tire is the one making contact, or that it actually has traction, it's fairly irrelevant where the other tire is pointing. I know a lot of guys justify their complete lack of Ackermann with this, as they would rather get as much steering out of the tire that has traction regardless of if it is the tire on the inside or outside of the turn.

Since I like having a vehicle with a body, it's not like I can use any more steering angle as it is. I've already got more than a factory XJ had, as opposed to most modded XJs that wind up with significantly less. :laughing:

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Re: The LBP XJ Cherokee POS

Post by Scoobienorth »

I think scrub radius matters far more on high traction surfaces, as if it isn't right it will dramatically increase the required steering force, and it actually forces the tire to break traction when being turned with the vehicle stopped (one tire has to move back, one forwards, fine with an open diff but with a locker it means something has to give).

Since I like having a vehicle with a body, it's not like I can use any more steering angle as it is. I've already got more than a factory XJ had, as opposed to most modded XJs that wind up with significantly less.

Not quoting the rest of that. But these are the two exact issues I’ve got. Full hydro or assist even it probably wouldn’t be as noticeable. But my steering box is supposedly as good as the Durango box the xj and the guys upgraded to and yet I couldn’t steer if I wasn’t moving it was so bad. And the extra sweep of the tire was so pronounced I feel the added strain was to much. Like my power steering fluid boiling from the constant back and forth while crawling in the deep snow. I also lost angle due to the jk Pitman arm but my ujoints can’t handle the tires I’m on so I left it as is.

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Re: The LBP XJ Cherokee POS

Post by Scott Cee AKA 2drx4 »

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Did a bunch of maintenance crap because it had been sitting. The TPS decided to die at some point, so it wasn't running great, which turned into chaos as I wound up having to spot weld a new arm onto an ultra-rare NOS OEM one because I couldn't get it adjusted otherwise. Added another RAM mount for a phone or InReach, didn't take a picture but I don't think you need one. Main reason for that was the speedometer no longer works most of the time, so I'm just using my phone. A bunch more lights died in the cluster, so maybe I'll pull it out and see if I can get the speedo working anyway; it's just super weird that a cable drive speedo is intermittent, I though it would be a totally binary thing.

I still need to swap the rear springs, they're getting worse. I still need to find a driver's window regulator that isn't stripped. I still need to put some sort of a splash shield on the intake at a minimum. A rear wiper that both exists and works would be cool too, also the front washer pump decided to die.

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Re: The LBP XJ Cherokee POS

Post by arse_sidewards »

HillBilt wrote: Tue Nov 05, 2019 10:40 am What really is a "perfect" Ackermann or scrub radius in the offroad department? with steering angles now into the 50*. (Legit question-not being an ass)

Ive got a terrible scrub radius right now with running front wheel spacers, and honestly don't even notice it at all, like zero. Still waiting on one to come off and hit a bus of transgenders :rainbow:

High speed off road only toys that get trailered everywhere notwithstanding I would just set the steering for best street performance. Good street performance will pretty much completely translate to good off road performance assuming your geometry isn't shit and causing things to go more than the typical amount out of whack as suspension cycles. Pavement is the highest traction surface and highest speeds these vehicles see so making it steer good there is the most bang for your buck when it comes to pleasant driving experience.

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Re: The LBP XJ Cherokee POS

Post by Scott Cee AKA 2drx4 »

I finally figured I'd try to fix the lack of rear speakers issue. I put this off for ages because I knew it would be a project that would take 10X longer than it should and cost too much for the reward. The main reason for this is the hatch had been hacked badly by the PO, so nothing would fit correctly. I bought some Kicker 6x8s from Cambodian Tire because they were on sale for $50 or something.


Made some mounting plates out of aluminum scrap:
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I made them at work with mostly the wrong tools. I don't do much (any) sheetmetal work there normally, and took most of my stuff home. So they're a bit rough. :laughing:

Butchered hatch:
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I added some adhesive here to help tie everything back together since it's fiberglass.

Bolted in:
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Added grills:
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I think I wound up with 8 hours into this crap between making the mounts, painting them, bolting them and the speakers in, figuring out the wiring, then cutting out the interior panel and putting the grills on them.

It actually sounds way better, so there is that. I might swap the door speakers out for some better ones too.

Now if I had a real muffler and wasn't subjected to constant engine drone noise I MIGHT be able to enjoy music while driving. :lmao:

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Re: The LBP XJ Cherokee POS

Post by Scott Cee AKA 2drx4 »

Went out to the lookout about the Nechako cutbanks. Most of the trail is a 2, maybe 1. :laughing: The last 2000' or so required 4wd. One of my hubs came unlocked trying to get back out of there so I had some troubles, plus the Gladiator before me really chewed it up. And I had 45PSI in my tires and didn't feel like changing that. :homer:
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Re: The LBP XJ Cherokee POS

Post by HillBilt »

Some 3 way interracial Jeep action going on there
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