For quite a while now, my B310 hasn't wanted to self center when you let go of the wheel. It has factory 13" wheels, widened out to 7". And cut springs, with shortened inserts.
My WOF guy (who is also a mate) knocked me back on it a few times ago. So I loosened off the free play adjustor screw quite a bit, (Some idiot had cranked it down quite a ways. (me)) and fitted the standard sunny wheels off my trailer with skinnier tyres. It was a bit better, and he reluctantly passed it.
The next time, he also mentioned that it didn't seem right to him. So I put the car up on blocks, pulled the wheels off, and stripped the suspention out. I removed the idler arm bush, and greased the buggery out of it. I also took the springs off the struts, and pumped the bearings between the top cup, and the top hat full of grease too.
Since it was all apart, I greased the thrust faces of the LCA bushes too.
The the car in the air, and the tie rods disconnected from the steering arms (so no weight on the drag link) I could wind the steering wheel from lock to lock with minimal effort. (ie, no tight spots. No undue drag)
Put it all back together, and no dice. It's still the same as ever.

Then, the other night I was on the book of faces. And the guy I bought the car off messaged me. as well as a VB210, he has a WB310. The 310 got defected for uncaptive springs. His front coils are aftermarket ones. So no incomplete coil at the top like my cut springs. (I had thought perhaps the incomplete contact circle at the top may have been cocking the top cup over, and jamming the top bearing)
Anyway, he went for the inspection to get his defect sticker removed, and he also got pinged for the car not wanting to self center too.
He's running fat feet too. at least 3x7, with likely more rubber than I'm running. If negative offset wheels were causing this, surely everyone would know sunnys do this. And there must be hundreds of guys with wide wheels on their 310s. So surely that isn't the cause?

Since it effects both of us, anyone got any suggestions?

Centering is mostly controlled by wheel alignment. If the toe-in is off it can have problems. If the camber varies from side to side it can have problems. But mostly it is the caster.

I think that highly offset wheels would make poor alignment more noticeable. Wide tires certainly affect wandering/tracking when traveling in a straight direction. Not sure is it affects self-centering from turns. The solution is usually more caster. Stock B310 caster spec is not much on the minimum side, but is 1 degree more tha B110 on the maximum side of the specification.

Personally in my datsun I liked non self centering. Made my car feel planted in corners and on the road. I never hadvan issue or noticed til crumb bought it and hated it lol.
It had always done it since I owned it.

It is a safety issue.
I had my wheel alignment done when I first put the car on the road. The wheel alignment guy (another mate) reckoned mine was the best sunny he's done. (he's done 4-5 sunnys easily)
That said, I have hit a lot of potholes since then. (so many my bump stops disintegrated) The roads here are f-king atrocious, even three yours on from our first big earthquake. (Ask revhead001)

The last idea I have left is to measure the min distance between the front of the front wheel arch, and the tyre. And then turn down more plain onto the castor rod. Crank the arm as far forward as I can..

Any other ideas?

what kind of springs you running? sounds like your weights out. does it pull just one way? or follow the camber of the road?

It just wants to go which ever way the wheels are pointing. So steer around a slight bend in the road, and you have to manually straighten up.

So my mate tried to fix his.
He cut 18mm off the crush tubes in his castor rod bushes. And cranked the castor rods up. He reckons it makes his wagon handle awesome. But it doesn't self center yet.

The SAI has a big effect on this, sounds like the primary effect?




Quote:
Are you using 610 (180B) struts? They have a less favorable included angle compared to the 1200/120Y or newer large Datsun struts e.g. 200B or 910 or 280ZX -- meaning less SAI for any given camber. At least reportedly.

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it's mainly castor. If you lower the car the castor rods become more horizontal and therefore longer, and you lose some of what little castor these cars had in the first place. Machine the castor rods to make castor adjustable extending the treaded section of the rod, or just as per the 1200 competition manual in the tech wiki.