To echo what's been said, the set-up was done wrong. At a gross level the following was not done (but should have been):

1) Set the ride-height for the car
2) Adjust the corner weights be adjusting opposite corners concurrently. So if the RF/LR diagonal is heavy, both of those corners should be adjusted up AND/OR the LF/RR corners should be adjusted down.

As long as the diagonal corners are moved concurrently, there should be little if any change in the ride-height of the car. It sounds like the shop may have been lazy and adjusted the corner weights by only working on one side of the car. Keep in mind that taking the rear suspension apart to make an adjustment (assuming that you don't have adjustable spring plates) is a drag, but it's the only way to make the adjustment.

It seems like there should be an easy way to determine if the tub is twisted - think of a sheet of paper, with four corners. If all four are in the same plane, it's not twisted.

Is there an easy way to check this on the 911 - just to be sure?

I appreciate the input guys. Here is what this week turned up.

Now the C/B is :
LF 606 RF 547
LR 897 RR 814

Ride height is
LF 24 1/16 RF 24 15/16
LR 25 RR 25 1/4

It is still off almost a full inch up front.

$500 was the cost of the first trip.... and another $500 for the second time around.

For $1000 you can buy your own set of digital scales, and do the job your self.

http://www.pitstopusa.com/INTERCOMPSCALES.asp

I'd feel ripped off if I was in your position.

Bruce Anderson says (Porsche specs) corner to opposite side corner variance should not be more than 40 lbs.

Rdane,
The chassis balance is acceptable despite the slight difference in ride height. This might be the best your car can achieve. I still think something is going on with the chassis. If they didn't include a weight on the driver's side equiv. to you, the chassis is off a little bit more. Raising a corner adds weight to that corner. If you reduce ride height diagonally, the weight goes to the other diagonal corner pair. Weight shifts around, it doesn't disappear.

The more disturbing numbers is the repeat bill for labor. If they did not get it right (close) the first time, why are they charging you full tilt the second go-round? I think you may have some legitimate issues with this billing procedure (depending on relationship, access to other chassis balancing shops, credit card limits, etc.). JMHO.

Sherwood
http://members.rennlist.org/911pcars

That's not too bad.

This could be improved easily, but it will require lowering the RR. John may be onto the key; the RR has reached the bottom of the adjuster range and going lower reqiures re-indexing the tbar.

That's a beach but the only way to do it right.

Are you saying the shop charged you a second time to fix the problem?

"That's not too bad."

But is it acceptable for $1000.... and more importantly should it be better if the car is straight?

"Are you saying the shop charged you a second time to fix the problem?"

yes

What exactly did you get for $500? Can't imagine a c/b costing that much - did they reindex the back end again or something? Might make more sense if they ripped something open - like charged you again for lowering. Otherwise, ouch.

That operation is usually about $150 give or take a few dollars.

Oh, and to answer the question, $1k and a noticable difference in height, I'd have a problem with.

rjp

When you measure to the wheel arch, it will never be perfect even if the tub is dead straight. The car has manufacturing tolerence and that is especially true of sheet metal. Measure to the arch and you measure an accumulation of tolerances.

That is why the factory specs height to the center of the Tbars, not to the wheel arch. But it is a pain to measure tbar height so most everyone just measures the arch.

Given that, I think it reasonable to see 1/4" variance left to right when measured at the arch. Try to get much closer than that and you start chasing your tail. Drive around the block, re-measure and you'll find everything has changed just a bit.

If you want to refine your measures, switch from wheel arch to tbar height.

Yours is 1/4" out in the rear, 3/4" in the front. That's still coarse adjustment territory.

Notice that the right side is high both front/rear. That should be an easy problem to resolve, just lower the right side. It's easy to correct a side that is high/low or an end that is high/low.

The vexing problem is a diagonal that is sitting high, and the opposite diagonal sitting low. You can't dial that out! It indicates either 1) bent tub 2) manufacturing tolerances as above. You don't appear to have that problem (maybe just a little).

In your particular case, it seems the right side needs to come down about 1/2" front and rear. That would bring you into my 1/4" range.

Now, the bigger problem with your current setup is the front ride height. Much too low. Euro heigh is 25 1/5 front , 25 rear. Your front left is almost 1 1/2" low! That is going to hose up your dynamic camber.

Hi Randy, I thought you were going to Bremerton this morning?

Actually they did pull the rear T bars again and go back to the alignment rack. As you can see by the numbers they did it all over. Original bill was another $1000 on top of the original $500 (ya $1500 total) I was charged but when I complained they knocked off $500 yesterday. Still not getting it right @ $1000 From what has been posted by others and the four local shops I talked to isn't OK.

When I left the shop yesterday the agreement was to look at it on monday after the auto cross.

Hi,

I think that's the other Randy (Randy W) who went - too many Randys w/ 911's in Seattle :)

Like Chuck said the settings are bound to change over time since everything on your car is fresh. Even within 1/2" at all four corners would seem acceptable given the newness This has to be accounted for -

You may want to consider cutting your losses, and get another opinion. Go somewhere else to get it checked - including the tub. If the tub checks out, authorize the correction of your car. Document everything of course. This will cost you a hell of a lot less than paying the same guys to redo what they did the other day.

Can only imagine all of this working by having a pro verify in writing that the chassis is straight. And thinking this is the only way you'll sleep at night.

Then work on getting your money back. It's awful to be at the mercy of people who aren't sure.

good luck

rjp

EDIT: Somenone correct me if I'm wrong, but that's BS having to rip the back end apart to c/b - they had it the first time! There's a 1/2" adjustment up / down either way - if they installed the new bars, the eccentrics should've been centered at the height 0you wanted THE FIRST TIME.

I have the same problem on my 73. I havent looked into it yet. I suspect laziness on the part of the shop that lowered C/B for the previous owner. I am going to attempt to straighten it out after I put in the bigger T bars. Sure does look funny from the back!!

Good luck

"if they installed the new bars, the eccentrics should've been centered at the height you wanted THE FIRST TIME."

They did put in the new bars and bushings at the same time (with a seperate labor charge for that work) before the alignment, R/H and corner balance.

Not trying to beat this to death just trying to figure out what it should cost and what I should do next to get the car right.