alignment problem
 

so i posted in another thread how after our trip to california the front tires were down to the belts from improper alignment - i got new tires which are 50 series whereas the old fronts were 55 series - this resulted in the front ride height being a little low - i turned the adjusters up about 4 turns without lifting the car and got it within 2mms of the recommended 180mm - fender height very close to 27 inches - drove it 15 miles and it stayed there - took it in to a shop that works on a lot of porsches - i told him about the previous alignment and that the car could not be lifted before adjusting - after car was done he said he didn't lift car, did all adjustments, everything was in spec - then he lifted it up to check if the front end was tight - said everything looked good but when he lowered the car back down it was about 20 mm too high - he drove it around but it still didn't return to the 180mm height he measured before lifting it - i drove it home (about 10 miles) and it's still that 20mm too high - so what happened here - should i just wait and drive it some more and see if it drops ... which is what i told him i'd do - he said he'd stand behind his work and if it needed further alignment he'd take care of it - he said he did not turn the height adjusters at all - so what do you think is going on here ???

Porsche 928 Aficionados-
 

Hey Honerboy - Just from my experience, if the alignment was performed properly, even when lifted later, your suspension should settle back down to the original set height after a few miles. I've rebuilt the front end on both a 1984 and 1985 928 and have lifted the front end many times after an alignment (brake service, tire replacement, etc...) and have had no problems with the ride height settling back to normal.

I've read where some of the more experienced Porsche 928 aficionados recommend driving up to 25 miles over a very rough road surface after an alignment to settle the front end.

Good Luck, Michael

Your ride height is based on the stock tires. If you put bigger or smaller tires on you should not adjust back to the factory height from a suspension geometry stand point. You should calculate the difference in size and add or subtract that to the ride height. That said it's not that far off that a new alignment would bring it back into spec. It should have settled back down. You could pull it back down off the front hooks (like a trailer tie down or similar set up) and see if it comes back up.

The Stepson (84 Euro)requires me to drive it a full 100 miles before it settles fully. I had an '88 that I could drive over speed humps in the Sears parking lot and it would settle completely. My experience is that every car has different rates for settling.

pete r - the old tires were used when i put them on - they were 215/55's - i used them because i was trying to get the car back on the road and they were here, free and had pretty good tread left on them - the new ones are 225/50's which is the stock size - the new tires definitely lowered the car so i did raise it back to the 180mm +/- 20mm that is says in the manual - the car has lowered a bit more since the first post (drove it up and down the highway for about 50 miles) but is still about 188-190 mm - so i'll keep driving it and see if it drops more - it never seemed to take so long to drop and i've had this car up and down on jacks untold times - but then i was never so paranoid about it and didn't measure it as carefully as i am now - the new tires are to blame for that - so would the fact that it was aligned at 180 and is now 188 affect the toe in setting - like too much toe in - or does it mean that if it remains within 180mm +/- 20mm (which it has) the toe won't change enough to matter?

just a follow up on this - after driving the car about 300 miles it seems to have lowered itself back to the set 180mm - i don't know why it took so long - the car is driving very well - at least on the short trips i'm limited to in the winter here - i'll keep a close eye on the tires looking for uneven tread wear

I find a 928 thats been off the ground for a while will take a few hundred miles to get happy with being settled,

sometimes drive for 50 miles then alignment ,
then come back in 1K miles and check it without doing any lifting