Thanks Mac.
Doing the work instead of throwing parts at it , Damn it! I have to know!

Bent? no damage report but bumper had been repainted before I got it. Been under it and looked but could never find even a hint of damage or repair. Think suspension height measurement locations would make squaring reference points?

Agreed, RoW030 is not that pleasant on crappy streets.

 

Sometimes throwing parts is acceptable. However, in this situation you can throw some very expensive parts at the symptom. If you throw the wrong parts...$$$.

Like you I'd want to know so I would fix the car properly.

Many older cars have repainted front bumpers. That in and of itself is not sufficient to suspect the car has suffered more severe damage.

A newish looking headlight vs. one that has some discoloration, differences in the condition of the condensers, a new looking wheel compared to the other that has suffered the ravages of time and tire changes, these can suggest the car has been in an accident and the differences arose from repairs.

(When my Turbo was repaired after a mule deer collision the factory condenser and radiator were a different color than the originals and the other side's hardware. I had the body shop paint the new ones to match the ones on other side.)

But an accident bad enough to bend the car should have signs of severe damage and repair from under the car. That underbody anti-rock chip resistant paint may be missing in places, or it could be very fresh. One or more new plastic underbody panels. Bent jacking points.

I'd point out the suspension/steering components could be different to, with some new and some old, but with the RoW... sometimes owners use an accident as an excuse or an "opportunity" to change suspension so one loses that "tell".

Your alignment guy should spot any issues, but maybe you need to ask? He may not volunteer this. Ask him if he is having to use up too much adjustment to bring the car into alignment. Now some of this might arise from the different suspension. He may have to go to the rail to say bring the camber into spec. But the adjustment on each corner will be the same or nearly so. What I'm talking about is asymmetrical adjustments, with one corner having its adjuster in the middle of its travel or range while the other corner having one or more adjusters cranked all the way to their max (or min) setting.

I'm not saying the car is bent only that that can be an explanation. But you have other things that can explain the car's behavior.

The odds are it is one of those. It is your task to find which one.

Oh reference points... that's tricky. There are many hard points that are to state the obvious critical they be in the right place, the right position, but many of these are only checkable by having the car partially torn down -- the wheels removed at least -- and the car placed on a special bench to which fixtures can be placed and the body's hard point locations checked for proper position.

There are not many things you can do on your own. As I touched upon above the alignment guy can sometimes provide some enlightenment regarding the car's condition.

(Again with my Turbo: Shortly after I bought it I took it to another dealer to have it aligned. The tech told me after he was done the car was one of the "straightest" he had come across. My point in relating this is the techs see a lot of cars, and get a feel for what's normal and what's not.)

Is the car's ride height good? That is even? That is something you can check on your own.

 

Remove you spacers and try it again, that is, just drive it. Likely that has a lot to do with it.

 

unfortunately, need the spacers for clearance

 

I would drive the car at night in a quiet paved area close to a hard wall if possible. It's amazing what you can hear at night that you will never hear during the day. Try to make your wheel bearings make noise by driving in small circles.

If you will observe your wheel/tire assembly spinning on a balancer, it's easy to see how much up & down or side to side movement it has, & therefore ride disturbance. If the tire/wheel passes you know to dig deeper, spacers ALWAYs mutiply any cumulative imperfections.

 

So I don't see anywhere in this post about the wheels you are running. I take it they are not stock. Can you post details? Are you running hubcentrenic spacers? If so, are they metal or plastic.

If your wheels are not stock, and they are two or three piece, I think you found your issue.

 

aftermarkets wheels at the moment, oe turbo twist and sport designs exhibit same issues. having spacers checked out, they are hub centric as a 5mm can be, with the locator screw. re-torqueing everything and looking for play with dial indicator. once I have a rotating mass base line, I will have a better idea what is going on.
Like Mac stated, may not show up when unloaded.

 

FYI, Porsche worse case run-out for total rotating mass (hub+rotor=.002" at the hub which equates to .0045" @ perimeter, 18" alloy wheel =.0275) exclusive of the tire is calculated to be .032". With my 5mm spacer and all surfaces cleaned I am at .025". These are my aftermarkets wheels, not great but within spec., so I will assume my OEs will be better.

We know where this leads, tires.

For high speed driving, do I dare mention the "N"

 

Not only what tire, but sizes & air pressures, & age of the tires.