206 replies to this topic

[rodomo]

I have just had a look at Moot's mate's panhard set up in this thread:

http://www.gmh-toran...=0

My understanding is that the Commodore rear end with parallel control arms and a panhard rod is superior to standard Torana with angled conrol arms and no panhard.

The reasoning is that the Torana rear end steers a bit like a skate board when cornering.

Am I correct?

This came up in conversation last week with a couple of forum members.

[micklx]

The parallel arm setup like a Commodre is superior when compared to the Torana angled setup. The Torana's can suffer from the rear suspension binding up under racing conditions when the control arms are trying to allow the suspension to move up and down as required as well as provide lateral support to the rear axle.
On a Commodore, the panhard rod supports the diff laterally allowing the control arms and bushes to only have to accomodate suspension up and down movement.

The drawback with a panhard rod is that as the suspension moves up and down the rear axle moves slightly to the left or right, this is where the watts link setup is superior as the rear axle stays located centrally.

[rodomo]

Watts on yours Mick?
(pardon the pun)

[Racehatch]

My car has an adjustable panhard rod, I am planning on changng that to an height adjustable watts setup though, as it will allow me the chance to be able to adjust the rear roll centre.

I agree with commentts made re the angle of the top arms... pig of a setup... really hurts the cars ability to get out of corners well under power (as it induces extra understeer) which I really noticed at Phillip Island. Currently looking at ways (within the rules of course) to get around this problem as I feel it will go a long way to improving the cars pace at some of the faster tracks..

[micklx]

I've just got the original Commodore Panhard rod.
If I ever get on top of the rest of the car, then a height adjustable Watts Link is on the cards.

The way I understand the I.P. rules, you can add links to the suspension but you can't remove them, so you would need to add a couple of upper links running fore/aft, and render the standard top arms useless so they do nothing, maybe make them out of celery so they flex ???

It's quite an art interpreting some of these rules, no wonder there have been so many arguements over the years.

[rodomo]

The way I understand the I.P. rules, you can add links to the suspension but you can't remove them, so you would need to add a couple of upper links running fore/aft, and render the standard top arms useless so they do nothing, maybe make them out of celery so they flex ???

So removing your original panhard and fitting a watts link would be acceptable?

With the Toranas, what if you were to brace the 2 top arms across?
Sort of like an "A" frame but perhaps with with a brace near the body and another close to the diff?
Would it be too strong?
Or would the bushes allow enough flex?

[Racehatch]

So removing your original panhard and fitting a watts link would be acceptable?

With the Toranas, what if you were to brace the 2 top arms across?
Sort of like an "A" frame but perhaps with with a brace near the body and another close to the diff?
Would it be too strong?
Or would the bushes allow enough flex?

Yes, you can change the panhard for a watts linkage.

Re the rear trailing arms on the Torana, unforunately you have to retain the original arms unmodified.. so the only option as mick suggested would be to somehow render them useless, maybe with "supersoft" bushes, and create an extra a arm setup, with the 9inch though, there isnt much room.. (although it has been done)

[Racehatch]

Group C ran panhards...actually illegally but they did...no watts but...careful boys...dont want any fights on rules this early..Lol!
R

hehe, dont worry Rory, this is for my IPRA sedan, I've got a hatch that I'll be building for the replica racing which these mods wont apply to

[Struggler]

FWIW my old Group C A9X had a panhard rod. It actually broke once at the rod end and the difference in handling was like night and day. I got a new rod end and refitted it ASAP.
I never would have thought it would have made that much difference.

[TerrA LX]

[TerrA LX]

Thats Ron Missen. He has done plenty for me as i have for him.
One of the MOST knowledgeable blokes to have ever lent a spanner.

[TerrA LX]

Didn't bother with the other end as optimum is as long as physically possible and level at normal suspension height so as not to arc too much during suspension travel.

Edit, you can just see the mount in the previous pic, do you also think that those outer arm mounts on the diff are angled up (rear ward) quite a bit?

Edited by ALX76, 31 December 2007 - 12:36 AM.

[TerrA LX]

The arc travel of a pan hard bar when the suspension moves up and down is what makes a watts link superior.

Edit, the longer the pan hard bar the less the arc travel.

Edited by ALX76, 31 December 2007 - 12:44 AM.