Well, I checked everything BUT the rack as I have IGN-1As mounted on the frame under it which are a major pain to remove. Kind of kicking myself for that but I didn't have a lot of time and there were other things that needed to get done. Everything else seemed totally fine and tight.

I think in my original post I may have exaggerated the effect on weight/unweight on the turning radius. On smooth pavement the car is very predictable. It's when you get into anything bumpy or uneven that it just feels all over the place.

I wonder if what I am feeling is tire flex, exaggerated by stiff springs, bushings & swaybars + sticky tires? I am running factory wheels.

 

Update: I was going through the thread @Sgtblue linked to and realized that I was chasing after the wrong bolts -- I was trying to get to the ones that are on the column that comes down from the steering wheel, not the two straps on the subframe. I did check the bolts on the subframe and they were tight. So either I am too sensitive, these tires just feel weird, or something about my combination of components just doesn't feel quite right. At any rate, I don't think there is anything "wrong."

 

A highly-damped stiff suspension, along with low profile tires inflated to their design pressure, likely 35+ psi, WILL lose traction over bumpy pavement. That's one of the main reasons why off-road vehicles have large low pressure tires and suspension with a lot of travel in an attempt to keep the tires in contact with whatever they're running over.

 

I would still check for ANY play in the rear (like your wheelbearing idea).

I once had loose bolt on my FC rear triaxial hub that had ~1mm slop and it made car drive to one side badly over continously bumpy road surfaces.

 

Some people have tested bump steer on the factory FD suspension geometry and have found it to be significant.


If I recall correctly, the FD geometry was designed to have toe changes during compression and rebound to add stability in certain situations.

Since my engine is swapped and the steering rack is not in the identical position that it was in from the factory, the tie rod angles created some bad bump steer and I was getting similar symptoms as you. After adjusting my outer tie rod end positions to get closer to zero bump steer, my car now feels significantly more solid and stable.

 

I just recently read on here someone with a lowered FD was setting up their front end and checking to see of they needed to use bumpsteer spacers and found the stock geometry had zero bumpsteer all the way theough to max compression.

The dynamic toe of the FD is in the front lower arm sliding bushings and the rear upper arm sliding bishings.

If these are shot the car will get wobbly.

One way to kill the bushings is to tighten the mounts with the car in the air and suspension at full droop (like when working on suspension.)

As the factory manual shows, you need to tighten them with the suspension at normal ride height (wheels on the ground or a jack under the tire/axle till that corner is loaded).

Otherwise the bushings tear from over rotation.

 

Would be keen to see what "more aggressive" alignment settings would be.
I am getting mine done and doing a bit of research online to see what people are setting it at, and for what use.

(For reference, I am super low, previously "stanced" but now going back to more drivable/racey spec. I'm very low, tucking tire, and on basically full adjustable suspension, looking for mostly street/mountain driving, with an occasional drift day. Tentatively looking to go with something in the region of -4/-1 deg camber, which is a big difference from my existing -5.5/-6 deg.)

 

Reading through my old thread list I saw this and wanted to update it: problem was the front swaybar was in upside down.

 

been a long time since I owned an FD, but my recollection is that the front swaybar was fairly flat and symmetrical, but maybe there was some angle to the arms I’m not recalling


.

 

The only thing that could be upside down is the links pointing above the lower control arm instead of beneath, putting the bar at a funny angle and maybe binding.

 

Yes the tips angle either up or down. It’s even depicted in the FSM. The bar should be installed with tips angled up.

 

R-24