what brakes are you running. on my h190 with a particular disc brake configuration the brake caliper was actually hitting the chassis (in fact the bleed nipple itself was hitting, which was a little bit of a worry)

do you have bump stops installed? did you shorten them?

did you do the top bushes on the chassis? they are hard to buy (in aus anyway) and often people don't replace them

it will be interesting to hear what fixes it in the end

Is the bump stop above the diff centre still installed? I had to remove the one in my coupe [H165 housing fitted] as the diff was pivoting on the bump stop under load when cornering.

Let me rephrase... Bind doesn't always mean a complete sudden stop like hitting bump stops. Hitting bump stop will certainly cause big snap oversteer, which as you is not what you are experiencing.
Bind means anything that is restricting the suspension from it's normal operation/movement. It can be an additional arm (eg traction rod) that is a slightly wrong length or set at the wrong angle and ends up fighting the movement of the leaf spring as they travel different arcs. Don't forget a cambered leaf spring's length changes as it moves up and down as well. Huge potential to get a traction rod setup wrong. It could also be a geometry issue. If the traction rod is creating some anti-squat geometry at that particular part of the suspensions travel, you'd get a reduction in available lateral grip. Or a sway bar fouling another component which increases it's spring rate, reducing grip. In those situations you get a much more gradual unloading of the tyre which I imagine could be consistent with what we see on the videos, rather than the big snap oversteer you seem to be expecting froma bind problem.

I'd love to see a pic of the suspension - I'm having a hard time imagining how that sway bar setup you described fits in there with a traction rod as well. It's much more likely to be either of those parts causing problems than shock absorbers.

1200rallycar the aluminum bushes in the chassis and the delrin bushes in the lower part of the front shackle are brand new.

Benny I removed the pinion snubber as well.

Harry thanks for the clarification, sorry works been kind of crazy so my brain was locked on a particular definition of bind.

The way the Addco rear bar attaches is as follows: There is a u shaped bracket that is mounted by drilling two holes in the chassis rail just behind spring shackle. The ends of the sway bar clamp to the spring and use a set up like the front sway bar bushings. I'll try and get a picture up. A few years ago I actually had to shorten up the rod that went from the spring up to the sway bar eye as it was fouling on the chassis rail.

As soon as I figure out how to resize the photos on my iPad I'll post them.

OK here are the pictures; ignore how far the sway bar bushing is pushed over, I put it that to see if the bar was fowling the bracket.

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  rear bar.jpg (23.23 KB)


  traction rod1.JPG (19.19 KB)


  traction rod2.JPG (18.09 KB)

slip disks between the leaves?

yep, based on the pics it looks like both of those arms could be working against the movement of the leaf.

sway bar arm is much shorter than the leaf so it will be travelling a different arc to the leaf, and it's almost solid mounted to the leaf - there's no link pin to take up any difference in dynamic lengths. You could test for a bind condition there by disconnecting the end of the sway bar and jacking up the diagonally opposite corner to compress the leaf 2-3". If the sway bar no longer lines up with it's mount on the leaf spring, that's an issue. Then test for bind in droop by jacking the front up on the same side of the car.

Do the same with tests with the traction rod unbolted at the rear. If the mounts don't align at 2-3" of droop and bump, you've got bind.

Harry, I pulled the standard 50mm-ish end links out of the set up because they were hitting the chassis rails. The issue caused a slow oscillation similar to low air pressure / cut tire. I had originally intended to use rod ends like I did on the front bar. Even though I did it I don't like the way I have the sway bar ends attached, so it's possible they are contributing to or causing the problem.

I'll be revising the links along with getting the end play taken care of.

I apprectiate you guys taking the time to give me some feedback; I obviously have no problem driving it as is but fixing it should help the lap times.

Tom, thanks for the pix - that helps. Looks like the Addco (?) bar you have is bass-ackwards from what the Datsun 1200 Competition Suspension manual calls for. The comp sway bar points the other way round, (with the ends pointed forward) and loops over the axle assembly. It does not mount to the body, but rather to the leaf springs with (2) bushings/clamps per side. Tension on the bar is adjusted by sliding the bushings forward or aft to suit conditions. I think that Trevor Harris had that design down pat from the day he laid ink to drafting paper.

Stan, as amazing as it seems I installed the bar according to Addco's directions.

It may be possible to install the bar per the suspension manual, the loop in the Addco bar isn't as deep as the one in the manual. The Addco bar dips to clear the differential snout and it may have enough clearance to be mounted per the manual.