[aosborn]

Originally Posted by 1971BB427

Never got into Autocross, but it is fun to watch. I built my '71 Camaro to be street driven, but handle well, and it does whatever I want, and usually more. I find I chicken out before the car has handling issues.
We like to take a drive in the summer up the windy Columbia River Gorge scenic highway, and push through the 10-20 mph curves as hard as our pucker factor will allow.

That is a great road, I have driven it many times myself. The next time you are out that way check out the road above the Maryhill Museum. SOVREN, the vintage road race guys, stage a hill climb there once a year. The road they run it on is the first paved road in Washington state and it is as curvy as a snake with a hunchback! I hope to run my Jeep on it sometime...

Maryhill Hill Climb

[kso]

Originally Posted by aosborn

... If you did all aluminum bushings in both the front eye and the shackle, I would bet that you could hang the rear end nearly level with no support on the opposite side. I might try that the next time I have the opportunity. ...

I think you should try that, yes...you might be surprised. More easily (and accurately to negate the effects of any frame or bracket flexing), you could just clamp any old leaf-spring set in a vice with a means to measure deflection angle and then apply a torque wrench to the end.

I see a lot of book-reading here but not so much book understanding, and the meaning of "bind" is pretty-much lost in the wind along with where arc does and does-not mean anything. Said as a guy who canyon-raced for years and has built both coil- and leaf-spring cars. Just how much difference there is dialing in roll stiffness using sway bars on the different suspension types would be enough to let someone suspect what's going on when leafs are working...then if you take some actual measurements you might have actual knowledge. "Just saying".

Anyhow, you got the "roll-understeer" thing, which is something that most people don't have a concept of.

[aosborn]

Look at the cars in my photo album and my avatar. Those are not theoretical, and they did not build themselves. There are plenty more where they came from.

What I am trying to do on these forums is to present a very complex subject in a way that is informative but not too heavy. If that is all you got out of my comments regarding leaf spring bushings and suspension binding, then you missed the point completely. If that is because I didn't explain it well, then my bad, if it is because you just didn't understand it, well...I tried.

Have a good day.

Andy

[MARTINSR]

Originally Posted by aosborn

Look at the cars in my photo album and my avatar. Those are not theoretical, and they did not build themselves. There are plenty more where they came from.

What I am trying to do on these forums is to present a very complex subject in a way that is informative but not too heavy. If that is all you got out of my comments regarding leaf spring bushings and suspension binding, then you missed the point completely. If that is because I didn't explain it well, then my bad, if it is because you just didn't understand it, well...I tried.

Have a good day.

Andy

Andy, you have explained things well enough for my brain to get a grasp. I am thinking that "someones" deflection angle is binding.

Brian

[kso]

Originally Posted by MARTINSR

I am thinking that "someones" deflection angle is binding.

Brian

Well, we're telling a guy to put a panhard bar on his 1st-gen Firebird, which 95% would not do (my Guldstrand-built Camaro road-racer doesn't have one) and saying that leaf springs don't twist, which is dead-flat wrong.

So...what is it about? This is helping?

Later.

[MARTINSR]

Originally Posted by kso

Well, we're telling a guy to put a panhard bar on his 1st-gen Firebird, which 95% would not do (my Guldstrand-built Camaro road-racer doesn't have one) and saying that leaf springs don't twist, which is dead-flat wrong.

So...what is it about? This is helping?

Later.

We were discussing it, my contribution was little more why I put one on my truck, and it wasn't for any other reason than to limit sideways movement of the rear so the tires wouldn't hit anything. We need to lighten up, I made a joke, that's all.

Brian

[NEW INTERIORS]

Only thing I was trying to point out here is.. By adding the panhard bar to fix one problem, Does it also create another one ???

Weighing out the real true benefits with a leaf spring set up..

I know Andy has some knowledge in chassis's,, But in the end is it worth the trouble to gain very little...

[1971BB427]

Same here. I understood, just didn't agree. That's what these discussions should be about, not about a contest to see how many will attack or flame.
I still think that the normal travel of a panhard bar is an arc, and as such it will try to push/deflect the springs sideways as the rear travels up and down. It's just not something I'd ever put on any of my vehicles.
If it's done because clearances are at a minimum, then those clearances must be enoughh that the arc of the panhard bar's travel wont push or pull the axle and create a further clearance issue.
By the way Andy, your build cars are amazing!

[aosborn]

SLO_Z28 1974 Z28 Camaro Autocross Test n Tune 2-4-12 - YouTube

Camaro...with leaf springs...

In the words of Forrest Gump... "that is all I have to say about that".

Thank you all for you input and insight.

Regards,

Andy

[NEW INTERIORS]

I would say someone needs to check that car out...

[MARTINSR]

Originally Posted by aosborn

SLO_Z28 1974 Z28 Camaro Autocross Test n Tune 2-4-12 - YouTube

Camaro...with leaf springs...

In the words of Forrest Gump... "that is all I have to say about that".

Thank you all for you input and insight.

Regards,

Andy

HOLY CRAP! That is wild to say the least!

Brian

[kso]

Umm hmm, it's a good video. At a vantage point about 12-14" above the stock roll center, it illustrates the result of body roll and a little bushing squirm. If what you really want is for the tires to not move sideways in relation to the body, you could use a panhard rod or watts link to raise the roll center but then you're back to fighting the leaf springs again and it will get skittish over bad pavement on corners. A better solution for the car shown would be stiffer (or just new) spring bushings and more roll stiffness via swaybars or spring rate.

But anyhow, I think we're all tired of this one and I'm not going to get anywhere with it.

For the original poster, see some light-but-knowledgable discussion pro/con specific to the panhard bar issue here:

Panhard Rod on a Leaf Spring Car