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Rear Anti Roll Bar with Live Axle
Antnicuk - 8/12/08 at 04:25 PM

I have heard various opinions on this. I have an Atlas on the back of my stylus and there is quite a bit of lean. It has a panhard rod and front and rear trailing arms.

I have a small tubular ARB on the front.

Am i better off just fitting a stronger one on the front and leaving the back or leave the front and fit one to the back.

Also, how does moving the locating points of the pan hard rod up or down affect things. I understand it is supposed to be as horizontal as possible.


John Bonnett - 8/12/08 at 04:47 PM

Hi, I'm no suspension specialist but in my experience if you stiffen the back either with an anti-roll bar or with stiffer springs the car will develop more over steer. Similarly, stiffening the front will give you more understeer. So, I think you have to address both ends to maintain the balance.

John


britishtrident - 8/12/08 at 05:10 PM

Is the car over steering or under steering ?

If under steer stiffen the back springs
If over steer stiffen the front anti-roll bar.


Antnicuk - 8/12/08 at 08:14 PM

very little understeer but the super soft R888's on the front and the 330 ftlbs at the back sees to that!

from pictures taken at the trackday the back end seems to tip up quite a lot but from the front it looks ok.


procomp - 9/12/08 at 07:51 AM

Hi

Dose the Stylus still run the Sylva style arms at the back. IE lower one forwards and the top one to the rear.
Or have they switched to a more conventional all four forwards.

Cheers Matt


britishtrident - 9/12/08 at 08:31 AM

Is the panhard rod more or less horizontal and how high is it above the deck with the driver on board ?


Antnicuk - 9/12/08 at 06:20 PM

the stylus runs 2 lower arms from in front of the axle and 2 upper arms from behind the axle.

The P/H rod is almost horizontal at ride height but is slightly lower at the end attached to the axle and is about 6-7 inches from the floor.

Its mounted about an inch higher than the bottom of the seat pan

[Edited on 9-12-08 by Antnicuk]


procomp - 10/12/08 at 08:17 AM

Hi

With that arm setup ( as per the sylva's ) you do not need an anti rollbar for sure. The arms are already trying to twist the axle during any roll. It would be wise to check around all mounting points both axle and chassis for cracking as the brackets are put under high stress during any roll. Especially if the bushes are old and firmed up. Make sure the bushes have plenty of compliance in them.

Panhard rod is also by the sounds of it in a std Sylva position. So not too bad.

You say it has an ATLAS axle in the back. if it has they are considerably heavier than the English axle and for sure will require dampers with specific valving to control the extra unsprung over the weight of the English.

Thing to try first would be play with the front bar. Try stiffening it if no real effect sounds like you could do with a stronger one. Most used on the Sylva / Raw strikers etc are of 7/8" - 1" dia tube depending on what length legs it is possible to get in and the space available for width.

Cheers Matt


Antnicuk - 10/12/08 at 12:44 PM

Thanks for that, My current ARB is only about 5/8 inch tube on max adjustment. Where can i get a thicker one from ? Its just a straight bar with a 45 degree bend at each end.

The bushes seem ok, i removed the arms at the weekend as i'm going to replace the bushes at the chassis end of the bars with rose joints and leave the axle end bushed, as i need to be able to adjust the axle slightly.

The atlas is heavier but i have a small disc conversion which is a bit lighter than the drums. I assume i would need to weigh the axle to know, but who would know what shock set up i would need?


procomp - 10/12/08 at 02:55 PM

Hi
For Antiroll bars for the strikers either Raw or sylva try Timgrey motorsport or Andy at AB performance. I supply both with antirollbars.

At the rear DONOT fit any rose joints. For adjust-ability you can make adjusters with bushing to give adjustment. With the setup they have you need as much compliance as possible. Other wise you end up with the axle or chassis brackets beaking off.

Cheers Matt


Antnicuk - 10/12/08 at 03:17 PM

I know Tim, i went to Abbeville and Rockingham with him. his mate has an RX7.

Do you supply to trade then?

Others have fitted rose joints to their stylus' and only had problems when fitting them both ends. With bushes at the axle end would this still cause a problem?

What other methods for adjustment are there that would take the abuse?


procomp - 10/12/08 at 03:31 PM

Hi i supply a lot of antiroll bars to the trade. Not wanting to step on Tims toes. He has a racing budjet to fund .

We have seen many occasions where even with rose joints at one end the brackets have ripped off. 99% of the time it's the one at the rear chassis that gives way first. End result is the axle going backward and the prop breaking at the rear UJ.
without the compliance the axle is just not allowed to sit on the ground during cornering which gives lack off grip from the inside rear. Bad news if an open or ATB diff is fitted.

Cheers Matt