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Reply to "Newbie with many questions"

Gordon Nichols posted:

Todd wrote: " I want to know if there is any safety reason one can not use two knuckle/u-joints on a steering column?"

Short answer - No.  But there's a yes involved, too.

Longer answer:  Sometime around 1972 and after car manufacturers started going to transverse (crosswise) engines in the front of cars, various governments started testing them for crash-worthiness and found that, on front impact, the engine would be forced rearward and often rotate, shoving the steering column straight back into the driver's chest and killing them.  This was especially true with the original Austin Mini.  That's what started the "crush cage" that VW went to on the beetle around 1968.

Other manufacturers used a shorter, centered steering column and an off-set steering rack and pinion, all connected by a short shaft with two universal joints, thereby providing for movement of the engine/transaxle/frame in case of frontal crash.  If you look closely at Wolfgang's photo just above, you can see how it works.  this method also allows for easier placement of the rack because it no longer needed to be directly inline with the steering column.

So, yes...  There is a safety issue with using two knuckles to connect the steering column to the rack.  It was done to improve driver safety in case of a frontal crash.  

It is currently the preferred method provided that the two shafts are off-set enough to never allow them to line up and become a spear in a crash. 

Doggone THANKS!  Your explanation couldn't have been better with photos.  I understand exactly what you are saying.  And now I understand WHY the previous owner/builder planned on using 2 u-joints.  Unlike a VW or 356, the rack and pinion steering is located behind the centerline of the front wheels and close to the firewall.  The steering box is not on center with the steering column and the arm from the steering box is angled.

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