Suspension travel upgrades on an 80

[SUMOTOY]

Agree, 6" or more of lift is needed to put the stock arms on top, the axle will needed to be bump stopped losing some up travel, but longer shocks are needed to get full travel and they need the extended stops anyway. that much lift is where the arm angle starts getting extreme, affecting ride and handling, I don't see any benefit to doing it with a lower lift.

Ok, I was hoping to keep on track with using stock ride height. Understand the advantage on a 6in lifted truck gaining more clearance than one even taller, but the thread was following the stock truck height for a while. Nay is up 3 inches now, and you are up 6, and WE is chopping rods to make them appear unequal. Seems maybe toyota made a good stock design that is tough to "optimize" further?

It depends on where and how you wheel, I have landed on the stock arms at the frame brackets a few times playing in the rocks, it hasn't been a problem, but I wouldn't want them any lower. The arms under the axle cause more trouble, they are easy to hang up on.

Nay was on the right track raising the front mounting points. I'd certainly think that rear bracket skid plates could eliminate a lot of hangup. Then again, if you are hanging up on the brackets, I'd venture you are already denting the transfer's skidplate.

A couple of interersting threads in the last few weeks on 'improving' a stock suspension to allow more capability. It appears static ride height is tough to improve, and adjustable ride height has it's own set of issues as well.

I'd be thinkin Nay's old 8in lifted jeep should be pretty reasonably priced right now...

Scott J

 

[Tools R Us]

Ok, I was hoping to keep on track with using stock ride height. Understand the advantage on a 6in lifted truck gaining more clearance than one even taller, but the thread was following the stock truck height for a while. Nay is up 3 inches now, and you are up 6, and WE is chopping rods to make them appear unequal. Seems maybe toyota made a good stock design that is tough to "optimize" further?

:whoops: on the stock thing. In stock forum the axle will flex just about the same as the shocks will allow? Adding longer shocks/lifts is where flex mods pay off.

...I'd certainly think that rear bracket skid plates could eliminate a lot of hangup. Then again, if you are hanging up on the brackets, I'd venture you are already denting the transfer's skidplate.

The bushing holder part of the arm is plenty beefy, a skid isn't needed, most of the time it's coming down off of a rock and landing on it, taking contact pressure off of the tire. When playing in the rocks with my I take it slow and easy, no problem backing up and taking a slightly different line. The transfer "skid" only has a couple of minor scratches.

 

[Cruiserhead05]

Wonderful.


You guys ruined the air bag thread, now this one is headed in the same direction.

 

[alkaline747trio]

So, could one benefit by installing longer shocks on a stock 80?

 

[Walking Eagle]

Wonderful.


You guys ruined the air bag thread, now this one is headed in the same direction.

sorry. I should not allow myself to get so irritated. It just really bothers me when I take the time to draw up a proper representation of what the real geometry going on is, and Sumotoy claims I'm fudging things- or basically calling me a liar. Guess the light of fact doesn't penetrate that far into the darkness.

I'll leave this bit of advice for anyone wondering what's happens with raising axle mounts, or dropping radius arm mounts, or flipping arms. Sit down with a piece of paper and a compass. Or take a couple of popcicle sticks and put pins through them into your workbench (not the wifes dining room table). You'll see the same thing I've drawn. Maybe some of you will believe the popcicle sticks more than a CAD drawing.

 

[Walking Eagle]

I changed one of the assumptions from dropping the axle brackets and putting the axle where it would be without dropping them to going out the full arm length and then dropping. Still the same result. The suspension path is not the same as dropping the brackets on the frame. I threw dim's in there so no one things I'm fudging things.

 

[SUMOTOY]

I changed one of the assumptions from dropping the axle brackets and putting the axle where it would be without dropping them to going out the full arm length and then dropping. Still the same result. The suspension path is not the same as dropping the brackets on the frame. I threw dim's in there so no one things I'm fudging things.

WE:
These are really nice Cad drawings. The problem is the givens in the equation. Let's be clear we are only addressing the front axle here for now (post 18)

* LG = LB
* "Stock mounting points" - only allowed to raise or lower perpendicular to the ground
* Stock mounting points = 2 locating points, one on either side of the axle. Hence
* the arc should center thru the axle, NOT thru a single mounting or pivot point.


You are oversimplifying the givens Heath. The arc at the front is the same. In fact, look at it this way to help. Cut off the mounting tabs from the bottom of the axle and put them on top of the axle (for ease of concept, just flip rod LB over and remount it to the top of the axle with the relocated mounting tabs). Now you have taken LB and raised it so it's mounting is exactly the same distance on top of the axle as it is on the bottom. So, you now have
* one level axle using the stock bottom mounts = LB
* one level axe using the same mounts located on the top of the axle = LG
* Axle center LG = Axle center LB
So,
*arc of LG = arc of LB

You have now raised the mounting point in front without changing the arc. Put another way, one of the givens here is that axle center is the same. You haven't shown that to be true, and it should be with a dual pivot point front mounting. And it actually reinforces Nay's conclusion that frame drop mounting should be avoided, given the choice.

Your drawings do not reflect the front or the rear axle, nor do they reflect the story problem givens. To help understand your error, try doing a zoom detail of the front mounting points (that's 2) with the givens above.

Scott Justusson

 

[landtank]

WE:
These are really nice Cad drawings. The problem is the givens in the equation. Let's be clear we are only addressing the front axle here for now (post 18)

* LG = LB
* "Stock mounting points" - only allowed to raise or lower perpendicular to the ground
* Stock mounting points = 2 locating points, one on either side of the axle. Hence
* the arc should center thru the axle, NOT thru a single mounting or pivot point.


You are oversimplifying the givens Heath. The arc at the front is the same. In fact, look at it this way to help. Cut off the mounting tabs from the bottom of the axle and put them on top of the axle (for ease of concept, just flip rod LB over and remount it to the top of the axle with the relocated mounting tabs). Now you have taken LB and raised it so it's mounting is exactly the same distance on top of the axle as it is on the bottom. So, you now have
* one level axle using the stock bottom mounts = LB
* one level axe using the same mounts located on the top of the axle = LG
* Axle center LG = Axle center LB
So,
*arc of LG = arc of LB

You have now raised the mounting point in front without changing the arc. Put another way, one of the givens here is that axle center is the same. You haven't shown that to be true, and it should be with a dual pivot point front mounting. And it actually reinforces Nay's conclusion that frame drop mounting should be avoided, given the choice.

Your drawings do not reflect the front or the rear axle, nor do they reflect the story problem givens. To help understand your error, try doing a zoom detail of the front mounting points (that's 2) with the givens above.

Scott Justusson

Anyone else having trouble understanding this criptic mess?

Is there a decoder ring available on EBay?

 

[sleeoffroad]

Man, what are we trying to prove here again? Tyler, you following all this. You started it, you better explain it

 

[SUMOTOY]

Anyone else having trouble understanding this criptic mess?

Is there a decoder ring available on EBay?

Ha:
Well, the pictures won't help you either then LT. The drawings in 59 and 66 show different arcs using the same story problem. It'd be so much easier if the arcs overlapped, since they do. It's kinda like staring at pirated pay for view...

Thought I'd help with the story problem, since I'm starting to see double staring at the pictures. I think too, WE has also buried a subliminal ad for hot chicks offroading 80's.... Squint carefully at those enormous 'orbs'.



SJ

 

[landtank]

RYA, I guess

 

[SUMOTOY]

Man, what are we trying to prove here again? Tyler, you following all this. You started it, you better explain it

Nay actually started it in post #2 Christo. I was just starting to think there was hope for us stock ride height boys, until post 15 and 18...

Since those posts, Nay is up 6inches, and TRU is up 3. Thankfully, you already offer those products at Slee. WE has Cad, and I just spent 150bux and put in airbags inside my springs.

Prove? Nada. I was optimistic that the thread could continue past post #2, but it got held up in geometry class.

Bummer.

SJ

 

[ed97fzj80]

The discussion was never limited to stock height, and 4" and 6" lifts were discussed even in post #2. The question was how to improve suspension travel. IMO, things were really going along just fine until post #41 when somebody who knows that he annoys somebody else made a specific effort to engage that somebody else in a debate . . . the result of which should really have been foreseen by that somebody. To put it less politely, somebody, intentionally or not, trolled somebody else, and somebody else swallowed it whole.

I'm not even going to get into how somebody else's drawings are perfectly valid since the rear attachment point of the front arm is fixed, so the front attachment point can be represented diagramatically with no loss of information. Somebody would just write a long, meandering, dissembling post pointing out the deficiencies of the problem definition in response to a statement like that.

 

[SUMOTOY]

The discussion was never limited to stock height, even in post #2. The question was how to improve suspension travel. IMO, things were really going along just fine until post #41.

You indeed can move the mounting point of the axle rod up and NOT increase stock ride height. I believe that was Nay's inference, and cetainly a reasonable conclusion.

Ok then, do we assume 15 and 18 to be true also? Ok, then we need to pick either cad 59 or 66 as true, because they both aren't by definition.

It's a mess, but it started at 15. By 18 it was in trouble. 41 only tries to straighten the course out. Without agreement on the basics, how exactly were things really going along just fine? I'm interested in applying my experience and BTDT of suspension designs to help work through some of the technical errors. No doubt there are a few in this thread.

The nature of a forum I suppose. I'm learning quickly that "80 Technical Forum" has to include the quotation marks on occasion.

Hope springs eternal. Carry on boys. WE, if you want to get straight on 15,18,59 or 66, feel free to take it private. Those 4 posts don't complement each other. I'd be happy to apologize for my challenge if we agree on your geometry.

SJ

 

[Hayes]

Somebody raised the LB of the LG that somebody diagramatically trolled in paragraph 3, section 2 of post #75 so that the angle of somebody's post about somebody else's post was acutely obtuse. Of course, if post 75 can't prove this to be true, then the length of somebody's radius in the LB is too short for the LG of line 1, and the travel of the center of sombody's axle will be decreased and the bump stop of somebody else's L-shock of the J-spring bracket point will certainly result in a nuclear implosion.

Now I get it.

Hayes

 

[ed97fzj80]

I have the solution -- the FLUX CAPACITOR!

 

[landtank]

I have the solution -- the FLUX CAPACITOR!

the flux capacitor is for the rear axle dip****.

 

[ed97fzj80]

Not on the '97s.

 

[landtank]

Not on the '97s.

I stand corrected

 

[Walking Eagle]

Ok then, do we assume 15 and 18 to be true also? Ok, then we need to pick either cad 59 or 66 as true, because they both aren't by definition.

did you miss this in post 66? "I changed one of the assumptions" conclusion is still the same. If you're going to change the mounting, you can mount it so the effective length is longer, shorter or the same. I show 2 of the 3.

It's a mess, but it started at 15. By 18 it was in trouble. 41 only tries to straighten the course out. Without agreement on the basics, how exactly were things really going along just fine?

The basics are the front axle is going to rotate around the mounting point. If you raise or lower that point, the radius of the circle is the same, the section of the arc is different, which changes the path.

If you change the mounting of the axle to the radius arm, you can change the effective length of the arm (the effective length is a straight line from the pivot to the axle). This is not the same as changing arm mounting on the frame, nor does it have the same effect on the suspension.

Hope springs eternal. Carry on boys. WE, if you want to get straight on 15,18,59 or 66, feel free to take it private. Those 4 posts don't complement each other. I'd be happy to apologize for my challenge if we agree on your geometry.

SJ

I'm plenty straight on all my posts - thank you very kindly. I don't need you to agree on my geometry for it to be true. It's true weither you believe it or not.



Lord - please give me the strength to stop replying and trying to educate the unteachable.