TB Front Axle

[ferricsteed]

Good day folks. Does the front axle with lettering ppint forwards like TA's or to the rear like TC's? My car is a loo ate TB, if one would qualify such a short production run as early or late. As is, it points to the front with
the top of the king pins angled to the rear slightly. I am assuming the geometry of sliding trunnions versus shackles changed the total castor angles; hence the axle change. (Total guess on my part)
Regards,
Tim Bloomfield
Hot Louisiana

[Steve Simmons]

Camber and Castor angles are the same as TC:

Castor 3 degrees (top of eye pointing toward rear of car)
Camber: 7 degrees (top of eye pointing away from car)

I seem to recall that the lettering on TA/TB is on the front, as opposed to TC being on the rear. But measuring the axle should tell for sure which way around it needs to be.

[ferricsteed]

Thank you Steve. Lettering to the front. Top of dowel rods thru kingpin "eyes" lean slightly to the rear.
Tim

[Tom Lange, MGT Repair]

Is there a consensus about whether or not to use the wedges?

Tom Lange
MGT Repair

[Steve Simmons]

Is there a consensus about whether or not to use the wedges?

Tom Lange
MGT Repair

Consensus, not quite, but most people will say to delete them. The wedges were added to lighten the steering by changing the castor angle, but in doing so they reduce stability. With aftermarket steering (VW or Datsun) the wedges definitely aren't needed since the low ratio of these boxes already makes the steering very light. I tried running both ways with my Datsun steering and didn't notice much difference, so I removed them. Ten years later I was working on the front end and... lo and behold... I didn't remove them after all. Guess I forgot. And the car is incredibly stable compared to most TCs despite the wedges being there. I plan to remove them (for real this time) one of these days. It will be interesting to see if I can tell a difference this time after driving with them for so long.

[mingle54]

The castor on the TB is the same as the TA which is 6 degrees (3 on the base and 3 on the chassis).
Prior to the wedges being fitted, the TC was 8 degrees (3 on the beam and 5 on the chassis), the wedges reduced this to 5 1/2 degrees. On my last TB I fitted the wedges "the wrong way round" thereby increasing the castor to 8 1/2 degrees, this improved the stability considerably.
Mike

[jddevel]

When refering to "wedges" are you discussing the caster shims?

[frenchblatter]

Jan, the "wedge" is an aluminiun wedge (like a slice of cheese) that was fitted between the axle and spring. It was mainly for the US market and is designed to lighten the steering. I took mine out as they have a detrimental affect on straight line running. I have a well set up bishop cam steering and have no problem. As an apprentice I was taught NEVER TURN THE STEERING WHEN STATIONARY. No if's or buts the car must be moving, no matter how slowly before the steering is turned.

[i.thomson]

Norman, your rule about not turning the steering until moving is the best reason i know of for banning power steering on small cars. Apart from being an unnecessary marketing ploy to sell cars to people who are unsure of their ability to park they are just another thing to go wrong. To make a tenuous link from this rant to castor wedges, power steering enables much higher castor angles to be used thus enabling the driver to concentrate on other things much more important than driving. Oh, and it makes extra profits for the sellers of track rod ends and enables drivers to make pretty swirl patterns in warm tarmac.
Just sayin'
Ian Thomson.