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260DET

Universal Anti Roll Sway Hollow Bar Kit

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The bar itself is straight and usually splined each end to accept the bar ends which are essentially levers that connect via links to a unsprung part of the suspension somewhere. There are versions made for using on the rear suspension of a drag car which look like they could be adapted to work on a Z car, at the front of course. But finding info on the wall thickness of the hollow bars used is like a Wikileaks exercise only harder.

 

Maybe someone here is using something similar on their race car that suits, if so tell us about it. I'm plain researched out.

 

EDIT Maybe a mod would like to move this to suspension.

Edited by 260DET

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I have seen a number of these on S30's and recently purchased one for the car I am building. Selection involves knowing the spring rate you desire. You can calculate the thickness you need based on bar length and arm length. Rule of thumb is use steel arms for heavier rates. You will need bent arms or bend them yourself. I have seen them mounted using flange mount bearings through the engine bay, fenderwells, and frame rails. I chose an aluminum bearing block I think I got from Pegasus.

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Great find, thanks. My race 280ZX has a OE big hollow bar on the front off some JDM Nissan sedan, so much lighter. It works well, will measure the OD and wall thickness and post them up.

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Well :) 1speedway have a 32mm OD hollow bar, the same OD as my JDM one. Mine has a 3.5mm wall thickness, 1speedway have a 3.2mm wall option. This is a great guide for what may suit mine, for anyone else my JDM bar is pretty stiff, no rear bar used, so if you want a stiffy the 1.25" hollow .125" wall 1speedway option may suit you.

 

Mine is soft mounted which is not good, one of the reasons for going this way is to have hard mounts. 

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My application is for a project Z car, anticipate making up and welding mounting plates to the chassis rails. Certainly for a S30 this would be necessary. Other than that my preference would be to use long links connecting to the struts which, if possible, will dictate the length of bar required.

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My application is for a project Z car, anticipate making up and welding mounting plates to the chassis rails. Certainly for a S30 this would be necessary. Other than that my preference would be to use long links connecting to the struts which, if possible, will dictate the length of bar required.

 

You really don't want to connect to the struts.  I know a lot of production cars do this now but for a racing car you're better off connecting to the control arm.  The reason being you increase the side load on your struts and that increases the friction that needs to be overcome before everything can move and the shock can do its thing.  

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Look at used nascar swaybar on ebay or go to Roush's outlet store and you can find anything you want.  A friend used one on the front of his 260 EP car.  He used the spherical mounts you can get for them and used the straight arms and then bent them to be close to the stock pickup location on the lower control arm.

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You really don't want to connect to the struts.  I know a lot of production cars do this now but for a racing car you're better off connecting to the control arm.  The reason being you increase the side load on your struts and that increases the friction that needs to be overcome before everything can move and the shock can do its thing.  

Interesting. I was actually considering this and had thought of attaching to the strut. Glad I didn't do it now.

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You really don't want to connect to the struts.  I know a lot of production cars do this now but for a racing car you're better off connecting to the control arm.  The reason being you increase the side load on your struts and that increases the friction that needs to be overcome before everything can move and the shock can do its thing.  

 Interesting point, hadn't thought of that. But if the links are aligned parallel to the struts then such side loading would be negligible?  The reason why I like the idea of strut connected links is that they can be long and so allow acceptable angularity when their location on the bar is adjusted in or out.

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I´m planning to use roll bar like this; it has hollow tube and adjustable knifes.

Mine is D.I.Y-kit, so it has to cut to proper lenhgt and weld those sleeves into it. Those blades are rotating, so you can adjust their stiffness.

IMG_0029.jpg

post-3341-0-28157500-1482209189_thumb.jpg

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I´m planning to use roll bar like this; it has hollow tube and adjustable knifes.

Mine is D.I.Y-kit, so it has to cut to proper lenhgt and weld those sleeves into it. Those blades are rotating, so you can adjust their stiffness.

IMG_0029.jpg

 

Looks awesome!

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 Interesting point, hadn't thought of that. But if the links are aligned parallel to the struts then such side loading would be negligible?  The reason why I like the idea of strut connected links is that they can be long and so allow acceptable angularity when their location on the bar is adjusted in or out.

 

The long links are appealing.  I've seen a lot of cars running the bar across like a strut bar and then you have the long link.  You could even hang the bar from the strut bar via rod ends to make a nice low friction mount.  I've seen a couple of touring cars use rockers on the ARB linkage so you can get long links and mount the ARB down low.  You can also fit droop and or pitch limiters this way.

 

As you turn with the strut mounted version you'll see offset that will sideload the strut.  Somewhere I read a quote from a touring car driver that mentioned he had fought understeer on their car all year and then it was solved.  When he asked the race engineer what the change was he said it was the ARB mounting location changing from the strut to the control arm (same wheel rate was seen).  Ideally it would be nice to have some hard data to back this up but I don't.  I just wanted to throw this out there as an FYI.  I personally was all set to do this myself until running across this.  When I took my first class with Rouelle I sat next to a guy who built some really trick cars.  He shared in class how changing the rocker geometry so that the pushrod/rocker/shock were in plane from the old setup where the pushrod was out of plane with the rocker made a large difference in front grip and driver feel.  

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OK, I'm convinced, bar links to terminate at the LCA's. To use longer links it might be an idea to mount the bar on top of the chassis rails, am going to have to fabricate mounting spots anyway and all that would be otherwise required are holes through the inner guards for the bar to go through. Thanks for the constructive comment chaps.

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The 00008 BSR car and I assume others ran a solid bar through the frame rails in the engine bay. They welded in a section of pipe and had the bar attached to the LCAs. I believe Bob said, soft springs and shocks coupled with stiff sway bars. Will ask JR next week when I'm in Connecticut.

 

I have one of the bars up in the shop and will check it tomorrow for any identification markings.

Edited by gnosez

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Got some 1speedway bits, it's all pretty massive except for the hollow bar, the steel arms are simply huge so they will have to be lightened somehow. The mounts I got are quite good, bronze bushes into which the bar slides so unless they are misaligned there should be no binding. I try to keep an eye on the weight of the bolt on bits whatever they are, got some work to do here.

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