Camber Conundrum

[Uwon]

‘78 chassis based hot rod with ‘86 based suspension +adjustable Konis , 930 brakes, RUF sway bar, Rennline strut brace. A-arm bushings and camber plates are in great condition and show no signs of squishing under load. Wheel bearing are new. Everything is nice and tight.
This is a road car with no track use.
My problem is that I cannot get my front camber to less than negative 1.2 degrees so it has that squatting bottom of the wheels out stance. Too bad boy looking for my taste.
The hood to fender spacing on each side is about 3-4 mm which I would consider normal. The Porsche issue camber plates are all the way out and to the back as far as they can go and are actually touching the inside fender structure. The strut brace helped to do this.
Anybody have any ideas as to how to correct this issue? Is there an aftermarket camber plate that addresses the desire for LESS negative camber not just more camber? My goal is negative .50 degree.
Thoughts please.
Thanks in advance.
Johan

[Tyson Schmidt]

You probably won't like this answer, but it's a function of ride height.

If you want stock camber you need stock ride height, which is unfortunately too high for most people.

[Uwon]

Good point Tyson. Forgot about that. No doubt it sure would be a major factor.
Forgot to mention that I have 930 rims/tires and 5 mm spacers at the front to clear the calipers.
Rolled fender lips as well. So I had to keep the ride height a bit up to not catch the fender when turning. See pic.



I don’t think that the car is particularly low, do you? My previous 911 had exactly the same setup (it was the donor) and I was able to achieve -.5 degree camber. Can’t recall whether the camber plates were at the outer limit though.
Guess I need to find adjustable camber plates. Question is which ones will solve the issue. Anyone?
Johan

[tobluforu]

Ahh, form over function. Its funny you use the term "bad boy", why because your car looks like a hot rod. I mean there is nothing about that car that doesn't scream, well... "bad boy."
Good luck.

[stownsen914]

Nicely done car! From the pic, the front camber doesn't look excessive, but pictures can lie sometimes!

Agreed that the ride height shouldn't be the issue - your car doesn't look that low. Do you know if your car has either decambered struts or offset lower ball joints? Perhaps a previous owner installed one (or both) of those items in search or additional negative camber? There are other things that could have been done to the suspension that would require custom fabrication and are less likely.

Scott

[stlrj]

QUOTE=Uwon;9884948]



I don’t think that the car is particularly low, do you? [/QUOTE]


Doesn't matter what you or I think, but you need to have any idea what factory specs are or does it matter? From what I can tell, you seem at least 2 to 2 1/2" below factory specs (but then, that's not how the factory measures it).

However, one of the benefits of extra negative camber is in a slight reduction in steering effort. That's the good news.


Cheers,

Joe

[Uwon]

Originally Posted by tobluforu

Ahh, form over function. Its funny you use the term "bad boy", why because your car looks like a hot rod. I mean there is nothing about that car that doesn't scream, well... "bad boy."
Good luck.

Touché !!!
Johan

[Uwon]

Originally Posted by stownsen914

Nicely done car! From the pic, the front camber doesn't look excessive, but pictures can lie sometimes!

Agreed that the ride height shouldn't be the issue - your car doesn't look that low. Do you know if your car has either decambered struts or offset lower ball joints? Perhaps a previous owner installed one (or both) of those items in search or additional negative camber? There are other things that could have been done to the suspension that would require custom fabrication and are less likely.

Scott

Good question. I can confirm that the struts, camber plates and ball joints are all stock.
I am not familiar with decambered struts and offset ball joints. Can either be used to decrease the negative camber?

[Uwon]

Originally Posted by stlrj

QUOTE=Uwon;9884948]
However, one of the benefits of extra negative camber is in a slight reduction in steering effort. That's the good news.
Cheers,
Joe

Good point.I'm always doing a bit of arm wrestling when parking because of the 930 rims/tires, spacers and no power steering. Then a bit of speed and it all disappears.

[Canada Kev]

Originally Posted by Uwon

I am not familiar with decambered struts and offset ball joints. Can either be used to decrease the negative camber?

They're used to INcrease the negative camber. That might be the reason for your more aggressive camber if they are installed.

[Trackrash]

I had this problem with my car. It is lower than yours BTW.

I did two things to get my camber to about half a degree negative.

First I took out the top strut mounts and made sure that I was getting them to go out as far as possible. It could be that you may have to enlarge the holes the mounting bolts go through or clear out some of the tar. You could use a jack to force the upper shock mounts out, if they don't want to stay put. Some have ground the upper mount some to allow it to go out further if it is hitting inside the fender.

The other thing I did was install a strut brace and use it to force the upper shock mounts apart. This may cause the gaps between the hood to enlarge some. I felt like it was worth the trouble on my car and the gap was not something most people would notice.


Good luck.

[Bill Verburg]

Originally Posted by Uwon

Good point Tyson. Forgot about that. No doubt it sure would be a major factor.
Forgot to mention that I have 930 rims/tires and 5 mm spacers at the front to clear the calipers.
Rolled fender lips as well. So I had to keep the ride height a bit up to not catch the fender when turning. See pic.



I don’t think that the car is particularly low, do you? My previous 911 had exactly the same setup (it was the donor) and I was able to achieve -.5 degree camber. Can’t recall whether the camber plates were at the outer limit though.
Guess I need to find adjustable camber plates. Question is which ones will solve the issue. Anyone?
Johan

Car doesn't appear to be particularly low, SC and 3.2 Carrera suspensions are the same except that different shocks may be used especially now that these cars are so old.

What are the wheel and tires sizes? They appear to be 16x7 & 16x9, 205/55 & 245/45?

running -1°(or more) in front is on the aggressive side but still not that bad I run -.8° on my street car and -3° on the track car

Do you have 5.5° +/- caster?



How about in back?

Wasn't that car in a big crash? If so How sure are you that the chassi isn't sprung? Did it go on a Cellite?

[Uwon]

Originally Posted by Bill Verburg

What are the wheel and tires sizes? They appear to be 16x7 & 16x9, 205/55 & 245/45?

How about in back?

Wasn't that car in a big crash? If so How sure are you that the chassi isn't sprung? Did it go on a Cellite?

You are correct with the rim and tire sizes.

Back is fine.

Chassis is an unmolested ‘78 from Arizona which was thoroughly checked out prior to the build. Although I did not have access to a Cellite, we did carefully measure against the factory specs and to our collective surprise they were sooo close.
The running gear and motor came from my crashed car save for unuseable bits and pieces.

[Uwon]

Originally Posted by Trackrash

I had this problem with my car. It is lower than yours BTW.

I did two things to get my camber to about half a degree negative.

First I took out the top strut mounts and made sure that I was getting them to go out as far as possible. It could be that you may have to enlarge the holes the mounting bolts go through or clear out some of the tar. You could use a jack to force the upper shock mounts out, if they don't want to stay put. Some have ground the upper mount some to allow it to go out further if it is hitting inside the fender.

The other thing I did was install a strut brace and use it to force the upper shock mounts apart. This may cause the gaps between the hood to enlarge some. I felt like it was worth the trouble on my car and the gap was not something most people would notice.


Good luck.

That’s exactly where I’m going now. I’ve dropped the struts and am enlarging the one hole on the tower that is preventing more positive camber.

With respect to the strut brace, I’ve been doing that and it yielded only .15 degrees in total. Unfortunately the Rennline strut can only be expanded by hand as there is nowhere to use a spanner.

Will post results in the next day or so.

[jjeffries]

Johan, your car is one of my favorites here on PP.
My 82 coupe came with a strut brace I have always though is a bad idea because it acts directly on the struts, or at least on the rubber of the upper strut mounts. I don’t know if these were commonplace at one point, but you **can** really crank in more leverage on the tops of the struts with it, i.e., in the direction of positive camber. I have since installed a conventional bar that braces the unibody. It might get you the results you want but maybe you too wouldn’t like the idea of this lateral force applied against the struts themselves. Best, John in CT

[Uwon]

Hey John, looks more like a guilotine LOL.
I agree that forcefully pushing the strut towers apart is probably not the best idea.
I have (rather reluctantly I might add) expanded the one hole on each of the strut towers which will hopefully yield the desired reduction in negative camber. Now just waiting for the paint to dry on the areas affected before re-assembly.
I’ll share the result in the coming days.
Johan

[Jonny042]

Hi Johan, I see you are picking away at the winter to-do list.....

One thing that strikes me is that if you've had to roll the fenders, already, anything you do to fix this issue at the top of the strut is going to make that clearance tighter. I wonder if you should look to the other end of the strut?

One easy (depending on your welding skills) solution would be to shorten your A-arms by an appropriate amount. Definitely want to measure twice

It seems people commonly lengthen them to increase camber so I know it's possible.

[Bill Verburg]

Originally Posted by Jonny042

Hi Johan, I see you are picking away at the winter to-do list.....

One thing that strikes me is that if you've had to roll the fenders, already, anything you do to fix this issue at the top of the strut is going to make that clearance tighter. I wonder if you should look to the other end of the strut?

One easy (depending on your welding skills) solution would be to shorten your A-arms by an appropriate amount. Definitely want to measure twice

It seems people commonly lengthen them to increase camber so I know it's possible.

Any increase in camber in the negative direction will increase fender lip clearance

[douglas bray]

I really don't get the zero camber thing we are trying to do here. I know men that forgo having children to have a car like this one and negative camber is a must have in that deal. My own lowly cab has raised and de-cambered spindles and it's a freakin' cab! Embrace the negative. Enjoy the negative. Look at it as a safety issue if you must. On a Porsche negative is a positive.

[Jonny042]

Originally Posted by Bill Verburg

Any increase in camber in the negative direction will increase fender lip clearance

If it's done at the top of the strut, yes. But if you lengthened the A-arm or use decambered ball joints, it will move the wheel outward and decrease the clearance.

Conversely if Johan was to shorten his A-arms to decrease his camber it would give him more fender lip clearance.