Alignment issues on 09 G8 GT

[Gascan775]

HELP Please,

Trying to get my 09 G8 GT back to handling like it should after some serious coin invested.

New control arms (both) up front, pedders strut mounts, inner and outer tie rod ends, sway bar bushings, UMI roto trailing arms and toe rods out back, adjustable sway bar links front and back, Koni sport adj struts and shocks all around, new sway bar bushings front and back.

Basically a new suspension all around - one constant since getting the car (second owner since 19,200 miles) to date with 96k the car would run straight, cornered flat and the wind in WI would hardly ever move this car. However, after 2 attempts no joy in getting the car to track straight. Seems to be searching (left or right) on highway but you’re always tweaking the wheel and the wind IS pushing me around now.

I have the alignment specs from the forum (Thank you all for documenting that). So I need a couple pieces of info and an maybe some feedback,

- Can’t seem to find anyone who knows "how" to correctly align the car here in Wisconsin. Any thoughts?
- Could really use some “actual” numbers from somebody who is tracking well (camber, caster, toe, etc...)

- The Koni install was purchased as a "kit" for all 4 corners, but it turned into one of these strut mod deals NOT new struts with cartridges. You have to drill and cut the strut case to replace the OEM cartridge with the new ones. If I had heard about this I would have gone to coil over route instead - NICE FREAKING PICTURES KONI!!!

Any insights (alignment shops in WI, good suspension settings (actuals) etc...would be great....

This mod may not have any bearing on the issue but it was a major disappointment and looking for feedback from others if they had issues with this set-up?

Ps - new tires with old suspension (ie: tired) ran just fine (as always). I was starting to get some wiggle at speed which was the push to freshen up everything.

Any insights (alignment shops in WI, good suspension settings (actuals) etc...would be great....also any potential things that could have been missed in install of all this, spring alignment, Strut mod, or ???

Thanks for any insights on this....

[WhatNext]

Since a lack of tight tracking seems to be the issue, that points to the caster being too low and not equal (driver side/pass side). You should have 4+ degs of caster on each side and equal. I think 5 - 6 degs would be ideal. What are your alignment readings for caster?

Since you replaced/upgraded your suspension, that most likely affected the caster. Just replacing my struts thru my caster off. Now to adjust the caster on a G8, you need caster adjusting bolts/cams which a shop won't have on hand. The GM caster adjusting bolts (92218339) can only add or subtract 0.5 deg of caster from each side (depending on the direction they are installed). Aftermarket cam bolts can do more adjustment (0.75-1.0 deg max) but cost more. I would go with the aftermarket ones for more adjustability.

Then there are expensive adjusting plates that replace the mounting at the top of each strut and allow a lot of caster and camber adjustment.

[roman1978]

WhatNext can you provide the parts for aftermarket adjusting plates or where they can be purchased

[WhatNext]

No, don't have the specifics on hand. They are shown somewhere on the forums.

[WhatNext]

Found it. Go to K-mac.com.

Like I said pretty pricey ($545)

Just to be clear - You don't have to go with the pricey strut top adjusters. More negative camber than allowed by the G8 factory parts can be done by elongating the upper hole that attaches to bottom of the strut and after market castor adjusters are ~$100-150.

[norm8332]

When I installed my LCAs I had an issue where the car wasn't lowered down to compress the suspension when tightening the bolt that attaches to the UB on one side. This caused an issue where the car was an half an inch higher on that side and the camber was off. Just thought I'd throw that out there because you mentioned control arms and the camber issue.