From Smoker to Sssssmokin’!

OK, this might help.
So this shows the top of the rails in the engine bay. The ARBs are originally attached to a captive nut on the the bottom face of the rail box section.
I've drilled all the way through and out the top of the rail with a 12 mm drill, then inserted a 12mm od, 10mm id tube through each bolt hole, ground it flush top and bottom and welded it to the top and bottom faces of the rail.
Then there's a spreader plate, and the ARB bolts go all the way through the rail and bolt externally on top.
(the spreader plates mainly hide my welding :))
IMG_2859.jpg
 
yellowz said:
Can you explain a bit further please Jon? I can't picture what you are saying and a quick interweb search hasn't made it any clearer. Familiar with crush tubes and bushes, but not for ARB fitment.
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If you use poly bushes on both sides of the compression rod joint (back to the chassis) the rod has a LOT less movement and acts as a spring, stiffening the action of the ARB. However not being designed for this, they have been known to snap, rather like a paper clip that is bent back and forth many times. This could have very bad consequences.

So what many people do is add a poly bush at the front to reduce compression of the bush under braking and a rubber one at the back to allow for movement. That way you get the best of both worlds.


Others use a rose joint which needs maintenance on the odd occasion but removes the flex under braking, with the added benefit of no vertical restriction.

https://technotoytuning.com/

9942cd9ae2b33530368ab591db5430b7.png



That is what Jon has been referring to.

I haven’t heard of the PMAC / Skidell trick before but it makes perfect sense. Especially as there have been reports of cracks at the ARB mounting point with uprated ones and no additional strengthening.
 
toopy said:
Thanks Ali, it's the fact the rubber boot needs to be cut that makes it far more obvious, i kept looking at pictures of it and just thinking, what am i missing, i just don't get it!
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That makes two of us ;)
 
franky said:
how long do standard ones last? I get the less movement, however given the excess of stress it puts onto other areas/parts I've never seen the point in changing?
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TBH I don't know. 10 years? They're rubber so they will deteriorate over time. My one is nylon and aluminium and I think it will last much longer.
which other parts does it puts stress on? we're talking about a ball joint, it reduces stress on the compression rod and reduces stress on lower control arm.
 
jonbills said:
OK, this might help.
So this shows the top of the rails in the engine bay. The ARBs are originally attached to a captive nut on the the bottom face of the rail box section.
I've drilled all the way through and out the top of the rail with a 12 mm drill, then inserted a 12mm od, 10mm id tube through each bolt hole, ground it flush top and bottom and welded it to the top and bottom faces of the rail.
Then there's a spreader plate, and the ARB bolts go all the way through the rail and bolt externally on top.
(the spreader plates mainly hide my welding :))
Click to expand...

Thanks Jon

Makes sense now!
 
jonbills said:
TBH I don't know. 10 years? They're rubber so they will deteriorate over time. My one is nylon and aluminium and I think it will last much longer.
which other parts does it puts stress on? we're talking about a ball joint, it reduces stress on the compression rod and reduces stress on lower control arm.
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What Franky says makes sense to me - being solid with no give at all, doesn’t it shock stress the mounting points and lower arm bolts more than they were designed for? The energy passed on by the braking force or impact of hitting a pothole will be the same but being solid it must be more of a shock load no? Having said that, there are no reports that I’ve seen of those areas showing stress fractures etc so it may be strong enough anyway.
 
AliK said:
What Franky says makes sense to me - being solid with no give at all, doesn’t it shock stress the mounting points and lower arm bolts more than they were designed for? The energy passed on by the braking force or impact of hitting a pothole will be the same but being solid it must be more of a shock load no? Having said that, there are no reports that I’ve seen of those areas showing stress fractures etc so it may be strong enough anyway.
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where would you rather have your shock loads - suspension arm in a plane it wasnt designed for, compression arm in a plane it wasnt designed for or a reinforced chassis mount point?
 
franky said:
wouldn’t you want it to work as designed?
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But wasn’t the design also a little flawed, hence geometry changing and the vibrations under braking + all these alternate solutions to try to fix it?
 
AliK said:
But wasn’t the design also a little flawed, hence geometry changing and the vibrations under braking + all these alternate solutions to try to fix it?
Click to expand...

Totally, however looking at all all the bits involved, its the limitation's of the chassis around those areas?
 
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