Ducman82

so i got my car back from the alignment shop. looks like the front camber is -1.8 driver, -1.9 passenger. wheels are close to the fenders so im going to half to
A- raise the ride height
B- roll the fenders
C- both

i had the alignment done because it was WAY off, and did not want to drive it like that for 50 miles etc till align it. how do i figure out the best ride hight for the car? WSM guidelines? or due to the wheels and tires do a custom jobber?

225/40/18 front
285/35/18 rear

David L. Lutz

My experience has been if you change the ride height, you will need to re-align again.

I also suggest check the height and compare to spec. in the WSM and go from there. I am running 225's 18in. and set within spec. there is plenty of distance between fenders and tire.

mark kibort

i believe that about 1-2 fingers space on the front tires to the fender is about right for a street 928. I run with the tire under fender lip, slightly, and i do drive a lot on the street, but have to be very careful. For looks, anything in the 140 to 155mm range up front is fine, as well as the rear. Still, roll the lip of the fender with a wooden baseball bat, very carefully. you have a race alignment now, so raising the suspension will give you more toe in as well. 1.7 degrees of camber, is where i found the best place of handling and tire wear, even for the street. 1.9 is getting to the edge. you could be burning up the inside edges with this much camber.

the WSM wants 180mm and that seems to make the 928 look like a 4x4 IMHO.

Mike LaBranche

Workshop manuals if you're running stock gear. 190 mm front, 175 rear. Changing ride height most definitely changes alignment, hence our insistence the tech not raise the car when doing same.

Ducman82

ya ill check the ride height tomorrow per WSM. now i need to find a wood bat that can be abused..... any tricks to that?

pcar928fan

Yea, you will have to realign once you rest the height. Seen so many bad fender rollings, I can't recommend this job...especially if you have never done it before! Asking for trouble!

Ducman82

ya i figured id get it redone anyway. ill check with body shops next week. see if i cant find some on that has the roll tool, just in case.

dr bob

I think thiis sums it up in a nutshell. If you want the car to "look cool" and you drive where there are no dips, potholes, steep driveways, speedbumps, or other road hazards, and don't care about tire life, try it at "two fingers space on the front tires to the fender." It may be perfect for Mark's race car that gets driven on the street to and from the track, but in my experience it's not the way to set up a car that you want to actually drive on the public roads regularly.

If you'd like the car to ride halfway decent, handle corners consistently well, keep the front tires going in the same direction most of the time, avoid the severe tramlining and bumpsteer issues, keep the spolier, AC compressor, alternator and oil sump on the car, and avoid the uneven tire wear that comes from severe toe change on suspension travel with the car sagged so low, try something closer to what the factory recommends. For the front, the lowest recommended setting starts you out at about 170mm, measured from the center pad rear bracket of the lower control arm to the ground. This measurement assumes new properly inflated tires of the original size, so you can adjust this recommendation slightly if you have worn or different-diameter tires. This adjustment number is after the car has been driven enough to get the suspension settled well. For used cars on used tires, the absolute minimum is 160mm, and that's a fudge number at best that allwed the dealers to avoid having to adjust and align cars that sagged during warranty. Stick with 170mm and you should be OK. Mine drags the spoiler on the driveway at 160, even driving at a crawl. 170mm (about 3/8" higher) is somewhat better, and 180mm means I can come and go without leaving plastic on the pavers.

Ducman82

Ok so i went out and messured. the rear is dead on at 175mm both sides, good to go there. i will just need to roll the fenders so it does not rub when i hit big bumps but great for now.


As for the front........ wow, it was at like....... 130mm. so i got it at about 183 184ish right now. i have about "3 finger spaces" or about 50mm from the flat center patch of the tire to the lip.. this look about right for 18 inch wheels?

Fogey1

There's this resurrected thread as well:
"Cause of sudden ride hight and camber change."
https://rennlist.com/forums/928-foru...-change-4.html

In which i posted:

Quote: Originally Posted by FredR
Your first action is to get the car on a platform lift and measure where your ride height is relative to the measuring points ... Fred R

+928, BUT ... no need to put the car on a lift. The measuring points are readily accessible to someone lying on the ground beside the car. You can't really use a ruler from this position, so I used a carpenters sliding bevel:
http://www.sears.com/shc/s/p_10153_12605_00939582000P

Slide the tool under, one side flat against the ground and tilt the other leg up to the measuring surface. Fix that angle/height/bevel and remove the tool. Then it's easy to put a ruler on it to measure the height.

You can do the whole car in five minutes or so.

Plus, plus also to using approximately the stock ride height. My front end was collapsed to <130mm when I bought the car and that's why I lost my alternator at a mild dip on a straight stretch of road at only 60-70mph.
__________________
Will

mark kibort

rear looks good, front I would drop an inch or so, but that would be murder on the toe. (it will toe out if you lower it as well as increase camber). so, you are kind of in a bind if you want it right

mark kibort

Bob, go buy a jeep!

stock specs make the car out to look like a 4x4. In europe, the ride hights are generally 1" lower, which is right around 150mm for our cars.

I run on the street and to the track, and on the track at 110mm front and 135mm rear. I have to be REAL careful. at 150mm, for years and years, no issues at all. my buddy at 140mm took out his alternator, but he hit a nasty pot hole, sued the city and won.

if you want you car to clear parking curbs, buy a suburban.

Dont even go there about tramlining, handling poorly, etc. lowering the car only helps in all areas.

mk

mark kibort

You forget that i owned a street 928 and used it in all the ways that it was designed, for over 10 years before I started racing it. 100,000miles, and another 40,000miles on that chassis, with a mix of racing as well, on the street and I had NONE Of the issues that you are saying that could happen. perfect tire wear! great handling and it looked great too. (2 fingers space at the front and just over the tire in the rear) . If you have had issues at this ride hight, then you need to find a different alignment shop.

Now, please dont take my advice if you are not planning to take the car to an alignment shop.

There are no issues with sligtly drooping tie rods. bump steer as described here on the list, is highly overrated. In my opinon, the car is much safter and the 180mm ride hight looks silly and causes the car to not handle as it was designed. again, my opinion. Just trying to help.

Ducman82

o its going back to the alignment shop this week. getting that done again, is cheaper then new tires.

WallyP

I disagree with Mark.

I would strongly suggest stock ride height - close to 170mm.