Just curious suspension question

[gathomas]

Prior to replacing most of my front suspension components, the car would jack up from the center jack support fairly evenly and both tires would come off the ground about the same time with the jack raised about 12 inches. Afterwards and with the front torsion bar adjustment screws in the same level, the jack had to be fully extended (19") before the front tire would come off the ground, long after the rear tire had. Does this mean that replacing the front suspension components (A-arm bushings, strut cartridges, ball joints and tie rod ends), affected the corner to corner balancing? Sorry for stupid question, but I want to get to a better comfort level of how much more work I have cut out for me to get it back to right (assuming it was there before I started). '78 SC

[tonythetarga]

If you took the a-arms off the car to replace the bushings, which I am sure you did, then the ride height has likely changed. Regardless where the front t-bar adjuster was, the t-bar spline position has moved. The only thing that holds the splines in place are the end caps which, when reinstalled, fix the ride height and corner balance once it has been correctly adjusted.
What does the car look like when sitting on the ground? Does the ride height look like it is supposed to?

[javadog]

You need to corner balance the car.

JR

[gathomas]

The ride height looks the same as before the work and there is approximately 3/8" difference from each side. I replaced the rear shocks a while back and now intend to replace the rear bushings. I guess a corner balancing will be in order after-wards. I am a bit surprised however that just in replacing the suspension components with like-kind (only new) would have so much of an effect on balancing.

[scotricker]

I've been adding my questions to the ride height thread...

and now I have to balance, too? Except I don't know what that means.

Is there a definition for corner balance?

No track for me (yet) just street. Do I even care? I mean should I even care?

[tonythetarga]

Originally Posted by scotricker

Is there a definition for corner balance?
No track for me (yet) just street. Do I even care? I mean should I even care?

Me thinks you should care. Street or track. Read this tech article.

http://www.elephantracing.com/techtopic/cornerbalance.htm

[javadog]

Originally Posted by gathomas

The ride height looks the same as before the work and there is approximately 3/8" difference from each side. I replaced the rear shocks a while back and now intend to replace the rear bushings. I guess a corner balancing will be in order after-wards. I am a bit surprised however that just in replacing the suspension components with like-kind (only new) would have so much of an effect on balancing.

Keep in mind that these cars settle a bit over time. There is almost no way that your car was balanced within Porsche specs before the changes and I'd say zero chance that it's balanced now. You can't really tell anything by measuring the heights of the fender openings, which is what most people do. It's not accurate and you can have a car properly weight balanced and the ride heights will vary. It's actually not easy to get the corner weights and ride heights all within spec.

JR

[scotricker]

thanks tony, I'll read that article...

[jkh2cpu]

12 inches to 19 inches? Sounds strange to me. Can you take a picture and post it of the car at 19 inches?

?

[gathomas]

I've been reading for weeks about corner balancing, and height adjustment and I guess I'm pretty close to tackling it. I understand it can be time consuming (read:frustrating) and tedious for the DIY, but also that if the car isn't tracked can be done relativey accurate, at least well enough to get it to the shop for an alignment all around.

Also, from jkh2cpu's previous question.......I believe you misunderstood what was being measured. The heights that were given were from the floor to the top of the jack plate not to any where on the car.

Just as a footnote on balancing beauty.......I had my F-car (308QV) up on stands once and I absentmindedly had one of the stands set one notch lower than the rest. To my surprise I could rock the whole car with one finger corner to corner!

[jkh2cpu]

I understood that you used to only jack about 12 inches before the wheels were off the ground. After a front-end rebuild, it's 19 inches, because the front wheel has more 'droop' when jacking the car. Such a change sounds odd to me. I've used the jack point for years... and I just went and did it again: the front is in the air first at about 12 inches off the ground, and the rear follows an inch or two later. Something is odd about this, and I don't believe it is corner balance...

[BK911]

Originally Posted by scotricker

I've been adding my questions to the ride height thread...

and now I have to balance, too? Except I don't know what that means.

Is there a definition for corner balance?

No track for me (yet) just street. Do I even care? I mean should I even care?

IMHO I wouldn't bother with a street car. If you are not pushing the car near its limits, who cares if its balanced? I would set the ride height and alignment and enjoy.

[911st]

Tripod it!

Jack up the car from the side jack point with a floor jack and side plate,

remove the wheels from that side,

lower it to the same level as the non jacked side,

measure from the ground to the centerline of the torsion bars or any place at that point front and rear.

Do the same thing on the other side and compare. They should be very close to the same or your balance is way off.

You can do this with the sway bars connected but better without.

Then equalize each side. If it is a street car this should be sufficient.

[javadog]

It's real easy to lock up a single wheel under hard braking when the corner balance is way off. Do this a couple times in traffic and you'll see the value of a corner balance for street driving.

JR