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Underslung rear ARB


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I have been driving my SL for the past few months without the rear ARB fitted because of problems during the build. Basically after sometime attacking the diff casing with a file I could not get the bar to anywhere near clear the diff. Fearing I was going to break through the casing I left it with a view to seeking advice. Sometime later when at Dartford I asked about this problem and was advised "nothing has changed, just remove more material". When I explained how much I had removed already an angle grinder was suggested.


Has anyone else been worried about the amount of material removal and / or used an angle grinder to obtain sufficient clearance? I'd like to get it fitted as the car is a bit understeery without it.





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The diff casing is pretty thick at that point. You should be able to remove 3mm no problem.


You can also file away the addiotnal material where the blocks sit upon the low chassis rail. All you need is the square mounting face on the end of the inserts.


Bending the ARB will cause the torsional force to be unevenly distributed along the bar in use.


Fat Arn

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I had the same problem, but sorted it by:


a) Removing about 3mm from the bottom of the diff ie completely filing away the rib around where the arb will pass

b) Carefully cleaning up the top of the inserts on the chassis rails (about 1mm gained)

c) Taking off about 3mm from the bottom arb mounting blocks.


I now have about 2-3mm clearance between the diff and a straight arb.

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Arnie's just not a bender - never will be; he's about the most homophobic chap I know in fact.


As regards the rear ARB, I had to remove a fair bit of material from the underside of the diff - a simple file did not suffice, we went at it with an angle grinder in the end; there seems to be a lot of material you can lose and I then cladded the bar with fuel hose to prevent erosive contact.


I thought the bar was more designed to perform its task by twisting or not, rather than bending iyswim. There again, I have a BA not a BEng so I am qualified to talk torsional rubbish.



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