Panhard bar question

[sunsetrunner]

...Where have you seen the SPC arms have camber adjustment? The arms I've seen are strictly caster, but having the caster corrected up top lets you have more room to use the lower adjusters to get camber tuned.
http://www.spcalignment.com/instructions/25480-INS_WEB.pdf
That claims they can adjust camber, but I think it's misleading. If they are camber adjustable, why do the different settings only show caster specs?

LR arms have adjustable camber and caster. You can slide the ball joint along the cutout on the arm, as well as all the caster spec settings shown on the instructions. I don't know how many degrees of camber this allows for but it is a decent amount. Source: I have LR UCAs and have had lots of alignments. Pic is from an FJ stolen off the Google, but similar.

 

[Tyler James Inc]

[MENTION=118730]AssBurns[/MENTION] that sounds spot-on. I'm no expert either, but that's how I see it as well. I do know a little(.5*) negative camber is desirable for better handling on the street. I also know caster helps with return-to-center. I believe toe largely affects tracking straight, but think caster has an affect on that as well. [MENTION=142071]sunsetrunner[/MENTION] thanks for that picture- that explains the camber adjustability perfectly.

 

[jkeith.w]

Not much needs removed. Here is a good thread.

http://www.toyota-4runner.org/3rd-gen-t4rs/154043-my-experience-trimming-35s.html

That's with what; a 2" BL?

 

[jkeith.w]

at 5* for tracking and driving . . . I had it aligned at that and drove it for months till the rubbing drove me nuts. . . Was aligned at 5*, 4*, 3* and now 1.7*. It drives perfect now. Clears my old 305s at full stuff and lock with zero rub.

So initially you had the SPC BJ at full rearward position and the LCAs canted forward to get the 5 degrees of caster, right? Do you recall (or do you still have the alignment sheet) what your camber setting was?

And currently your SPC BJ is in the full forward position (same upper BJ position as stock arm, caster-wise) but you ARE using the SPC for camber, correct?

You do/don't have a BL?

What is your wheel width/offset and spacer width (if any)?

 

[JayRolla]

So initially you had the SPC BJ at full rearward position and the LCAs canted forward to get the 5 degrees of caster, right? Do you recall (or do you still have the alignment sheet) what your camber setting was?

And currently your SPC BJ is in the full forward position (same upper BJ position as stock arm, caster-wise) but you ARE using the SPC for camber, correct?

You do/don't have a BL?

What is your wheel width/offset and spacer width (if any)?

With spc arms at the rear I could have gotten 6*. Cams had more adjustment.

Camber is zeroed on both alignments.

Most alignment shops won't do what is needed. I had to put spc arms forward. Max the cams myself and set spc camber to zero as close as I could. This way camber was so close the shop would not mess up and barely moved the cams.

I have 1.5" BL. Stock rims. 1.25" wheels spacer.

 

[jkeith.w]

Thanks - that's extremely helpful!

So, with SPC full forward (stock caster position for UCA) and your LCAs canted forward, you are at 1.7 caster, zero camber. Are the LCA adjusters maxed for forward movement of the lower BJ as it is right now? - you said they barely moved them..

I need to measure and see what the most positive camber setting of the SPC is compared to stock... (although I prefer a separate camber adjuster!)

 

[JayRolla]

Thanks - that's extremely helpful!

So, with SPC full forward (stock caster position for UCA) and your LCAs canted forward, you are at 1.7 caster, zero camber. Are the LCA adjusters maxed for forward movement of the lower BJ as it is right now? - you said they barely moved them..

I need to measure and see what the most positive camber setting of the SPC is compared to stock... (although I prefer a separate camber adjuster!)

LCA cams are maxed. I maxed them before alignment so they didn't need to adjust much.

Camber adjustment on spcs is extreme. You can pretty much set the tires in a V sitting on sidewall. You have to adjust them with no weight so the camber needs fine tuned worth lca cams.

Even though my spcs are forward in stock location I seem to have way more firewall clearance than stock uca's. Geometry seems different even though it shouldn't be. Seems tire flexes up into wheel well instead of back into firewall giving me tons of clearance.

 

[poopypants]

I run his same setup and I know I have more up travel than his pics even with my lowered bump stops. Guessing he has sway bar connected without longer links and/or no relocation brackets. You really don't know if your maxed till you start to get a tire off the ground.

I'm guessing he can compress almost 2 more inches.

No, I run longer second gen links.

More than enough to cycle my suspension to the extent that my shocks allow.

 

[poopypants]

I'm more concerned about any weird effect that a raked panhard bar (which places the two pivots in the rear suspension at different heights and distances from the centerline of the chassis) may have on steering inputs than the seemingly insignificant axle-centering changes. In terms of body roll, what happens when steering left? Does it pivot from the axle end of the bar (low RC)? When steering right, does the body then pivot from the frame side (high RC)? My truck has a tendency to step out under throttle in wet conditions when steering left - how much of that is attributable to an artificially low RC because of my raked bar? What happens in emergency lane change situations (left/right/left) at speed? Or when off-camber/pitched over to the right negotiating an obstacle off-road? Too many unanswered questions for me that I don't have to think about with the bar leveled.

On top of that, I've also noticed that at least one of the popular adjustable panhards have right hand threads at both ends - making it coarsely adjustable. You certainly aren't dialing in small bar-length adjustments/corrections without having left/right threads, so I'm doubting that I could address the axle offset from my ~2.5" lift with any precision with one.

:shrug:

Agree completely with the first paragraph. And it does EXACTLY what you said with the roll center differences for cornering one way out the other. I could definitely feel that before correcting mine.

As for the second paragraph... I'm confused... What difference does it make about the direction of threads if you just take the bar off, adjust each side, then replace?

 

[poopypants]

so, just saw this on crazydubman's thread:

:wow:

things get weird when both sides droop.

That looks like more than 1/4" to me...

 

[poopypants]

I'm with you [MENTION=28464]eimkeith[/MENTION] as far as the axle being centered not being a major concern of mine. Haven't measured, 'cause I really don't care. I do care about it shifting when equally compressing, as well as handling characteristics.
Since [MENTION=118730]AssBurns[/MENTION] asked about up-travel on the OEM LC/extended billy shocks, I took some pics. Also some pics of the PCK axle bracket clearance to the crossmember. Not very helpful with my lack of up-travel. I did, however, verify outboarding clearance between tire and frame, as well as took a look at the lower mounts again.

"Clearance" shot-

Outboard space shot-

Video- attempting to show its at full bump-
https://vimeo.com/199398709

Thinking mines actually fully compressed now?

Ps, mine wss shot in the dark, with a flash, but my tire was about another inch into the wheel well over yours... But that may be tire size difference ? 285/75/16 here

 

[Tyler James Inc]

That looks like more than 1/4" to me...

Haha well yeah, but that's sitting much "lower" than a 4" lift too [emoji6]
And I never thought yours wasn't fully compressed; I know these longer shocks don't provide a ton of up-travel.
Maybe yours was more tucked because your other side was more drooped- know what I mean? That would make sense for sure. My tires are 315/70R17, FWIW.

 

[jkeith.w]

As for the second paragraph... I'm confused... What difference does it make about the direction of threads if you just take the bar off, adjust each side, then replace?

having opposing threads at opposite ends allows miniscule (exact) length changes - whereas having same threads at both ends allows 1/2 turn/thread pitch change (coarse) increments only. This is why tie rods have opposing threads.

 

[poopypants]

having opposing threads at opposite ends allows miniscule (exact) length changes - whereas having same threads at both ends allows 1/2 turn/thread pitch change (coarse) increments only. This is why tie rods have opposing threads.

No, tie rods have opposing threads so that they can stay mounted and the jamb nuts loosened and then lengthened or shortened by spinning the center sleeve during alignment then immediately tightened with the jamb nut and set.

This really isn't a necessity on the adjustable pan hard. Take out the bar, measure the hole to hole distance, adjust the hole to hole length identical on your pan hard and your done. A half turn is not enough distance on a panhard to make a difference, it's not a fine tune item like a tie rod with a fixed length... You load up the back of your Runner and it will move the pan hard horizontally as much as a half turn "course adjustment".

 

[jkeith.w]

I think you're inadvertently proving my point: looking at the minuscule length changes needed to recenter the axle (see my drawing) - using repositioning as motivation for an adjustable panhard but then creating one without opposing threads for fine adjustment is nonsensical.

(And tie rods and almost all suspension links have opposite threaded ends specifically for exact adjustment, as I said.)


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[Tyler James Inc]

This really isn't a necessity on the adjustable pan hard. Take out the bar, measure the hole to hole distance, adjust the hole to hole length identical on your pan hard and your done.

Why would you get an adjustable panhard if you just matched it to your static panhard?

 

[JayRolla]

Why would you get an adjustable panhard if you just matched it to your static panhard?

When the panhard is removed does the axle realign when its off the ground? I thought I heard someone mentioning that the stock panhard when installed is pulling the axle over? Just a guess.

 

[Tyler James Inc]

[MENTION=50342]JayRolla[/MENTION] since the upper and lower links are symmetrical, [when the panhard is removed]the axle should be centered under the frame. On or off the ground.
Yes- when lifted- the stock panhard will pull the axle to the passenger side. The adjustable corrects that, but not if you match it to the length of the stock bar.

 

[JayRolla]

[MENTION=50342]JayRolla[/MENTION] since the upper and lower links are symmetrical, [when the panhard is removed]the axle should be centered under the frame. On or off the ground.
Yes- when lifted- the stock panhard will pull the axle to the passenger side. The adjustable corrects that, but not if you match it to the length of the stock bar.

He didnt say match the stock bar. He said remove stock bar. Axle centered. Measure hole to hole. Adjust bar to this measurement and reinstall. Since the axle centers with it removed the new measurement will give you the amount needed to adjust the bar.

At least thats how I read his post.

 

[jkeith.w]

That's how I read it also.


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