Rennlist - Porsche Discussion Forums

Rennlist - Porsche Discussion Forums (https://rennlist.com/forums/)
-   928 Forum (https://rennlist.com/forums/928-forum-69/)
-   -   alignment (https://rennlist.com/forums/928-forum/1138116-alignment.html)

dsweet928 04-11-2019 07:55 PM

alignment
 
installed refurbished steering rack on my 1984-S (great deal by Roger at 928sRus BTW) and put on new tires all the way around so an alignment was in store. Alignment shop got the front and right rear aligned but the right rear was way off. Any adjustments made it worse. Could see no indication of anything bent or out of whack. Anybody had this experience or know of what to possibly look for?

dsweet928 04-11-2019 07:56 PM

sorry, front and left rear were good, but right rear was the issue

dr bob 04-11-2019 10:04 PM

Share a picture of the alignment report so we can see what was out of whack.

Common stuff:

-- The upper dogbone link bushings collapse, so can't get camber correct.

-- Rear ride height sagged so can't get camber correct.

-- The lower control arm lateral "spring" plate is bent by a tow-truck or transport driver who loops a rear tie-down or recovery strap around it, then pulls. Prevents the rear toe from setting correctly.

-- The camber adjustment has hogged out the relief and hole in the crossmember. Carl sells a repair piece that goes in the opening to help with this. 928 Motorsports.

-- Accident damage.

dsweet928 04-13-2019 12:02 AM

alignment report attached

https://cimg0.ibsrv.net/gimg/rennlis...0cf8a14ea0.jpg

worf928 04-13-2019 03:06 AM


Originally Posted by dr bob (Post 15767832)
-- The lower control arm lateral "spring" plate is bent by a tow-truck or transport driver who loops a rear tie-down or recovery strap around it, then pulls. Prevents the rear toe from setting correctly.

Based upon the alignment report.... this---^

Here's a picture of the bent part to which Dr B refers:

https://cimg0.ibsrv.net/gimg/rennlis...3a6ccf6844.jpg

FredR 04-13-2019 04:19 AM

The morons who recovered my late 90S4 after my wreck did exactly what you see in the photo above- easy to spot that type of damage. That amount of error should trash the rear tyre rather quickly I suspect- have had a breakdown recovery recently?

Other than that no idea what else it could be given the adjustment is so far out other than chassis damage that is- any history of damage?- is the car new to you? Stuff like this does not happen overnight due to wear.

dsweet928 04-13-2019 11:39 AM

Have had the car 2 years and slowly rehabbing it. Not sure of damage history unfortunately. Will take this much appreciated feedback and investigate further. Thanks all!

dr bob 04-13-2019 12:37 PM

A bent spring plate is common and is easily naked-eye diagnosed by looking up and from the floor just behind the rear tire. It's an all too common bit of damage, unfortunately. There's other destruction available at the front when a recover effort includes straps or chains around the steering and under the nose. These point to the need to keep the "tow eye" handy and the threaded receivers clean and ready for any recovery effort. It's worth testing the tow eye in both front and rear receivers to make sure it will work when you need it.

Once a car is on a flatbed for transport, the front factory tie-down hooks are the best place to secure the chassis. In the rear, there's no similar hook so the process gets to be more interesting. Ideally, a tow strap would loop around the trailing tube of the lower control arm without grabbing the spring plate, but that's work especially if the car is damaged. The tire-net style of hold-down is OK. I've seen tow straps looped through wheel slots/spokes, but with those the finish on the wheel is at risk if towels/rags aren't used in there. Carl Fausett at 928 Motorsports offers rear tie-down adapters that fit where the rear lower link pin and the anti-roll bar link fit to the lower control arm. These pieces are an ideal solution, plus offer some minor adjustability for the anti-roll bar action.

Used and rebuilt rear control arms are available from 928 International. The rebuilt arms come with new rubber. The rubber bits may still be available separately from Porsche, as you'd want the damaged side and the other side to match when you are done. The front bushing mount rubber is critical to correct "Weissach" function, and the 35 year old pieces on the car now may have stiffened up a tiny bit since new.

That upper dog-bone link has replaceable bushings. Where the inner end connects with the crossmember, the camber adjuster hole gets hogged out if things aren't maintained tight. Carl has a steel repair insert that restores adjustability. Dog-bone bushing wear and load are exacerbated by low rear wheel offset numbers and spacers.

worf928 04-13-2019 12:38 PM

The problem with that bent piece is that, if you are a tow truck driver on hands and knees looking under the rear, it looks like a big thick hunk of metal. It is very not obvious that it is 'wafer thin.'

Wisconsin Joe 04-13-2019 12:45 PM

What about using the rear suspension crossmember, right under the transmission?

worf928 04-13-2019 03:14 PM


Originally Posted by Wisconsin Joe (Post 15771134)
What about using the rear suspension crossmember, right under the transmission?

Rear tow eye to pull onto flat bed. Through the wheels for tie-down. You need a spot where the ratchet straps won’t slip. Too much ‘stuff’ on the cross member that can/will get broken (wheel hub harnesses and brackets. )

EDIT: e-brake cable on the cross member right under transaxle.

Carl Fausett 04-15-2019 05:00 PM

We have all seen more damage caused by a careless tie-down than it would cost to install a good tie-down and avoid the damage to your car all together.

Here is a good and easily installed tie-down. The adjustable drop links are optional - you can order the tie down hooks alone for $159.00, mention "Rennlist" when ordering and take another 10% off.

https://928motorsports.com/parts/rea..._bar_mount.php


https://cimg3.ibsrv.net/gimg/rennlis...01b28147cf.jpg
https://cimg6.ibsrv.net/gimg/rennlis...c0660d7343.jpg
https://cimg7.ibsrv.net/gimg/rennlis...951145de95.jpg
https://cimg9.ibsrv.net/gimg/rennlis...8777c270d3.jpg

dsweet928 04-16-2019 09:25 PM

the car was transported on auto hauler from St Louis, Mo to me in Lexington, KY back when I bought it. Maybe it happened then.

FredR 04-17-2019 04:30 AM

Sadly that would explain what you have found.


All times are GMT -3. The time now is 06:59 PM.


© 2024 MH Sub I, LLC dba Internet Brands