Ride Height............,Again

Joined
Feb 12, 2023
Messages
62
Reaction score
122
Location
New Baltimore, MI
Ok.....Here's question.
I just put my 69 fury back together. I rebuilt the entire front suspension, and did a factory disc setup on it. I set the ride height. From my eyes, the ride height looks good. I did the factory procedure from the shop manual where you measure from the lowest point of the lower ball joint and from the adjusting blade. I still have what seems like a long way to go when I measure distance a from distance b with respect to the floor, the difference is only an inch or so. Factory spec. is 1 3/8".
Seems like if I keep raising the torsion bars I'm going to be significantly higher than I originally was. I also marked the torsion bar bolts when I took everything apart, and I'm right where I started. am I missing something stupid, or am I just being over cautious?
I know fender height isn't the proper way to do this, but my fender is about 27 1/2 inches off the ground.
Any thoughts?
 
If you freshly rebuilt with new bushings and seals keep going up to the factory ride height. What you don’t know is who adjusted it prior to you to maybe try to lower the front and raise the rear. Even the factory setting is not that high. I found that when I rebuilt my’68 Polara I set it to factory height and after driving a few hundred miles as the bushings settled in I had to re-adjust. Set it drive it re-check it. If it still looks a little high then next step is to look at your rear spring sag. On the front, too low you may bottom out or get a too spongy floaty ride.
Set it to spec, drive, recheck. Then maybe tweak it to your look and ride preference.
 
When we replaced the lower control arm bushings in my '67 Newport, I went through some of the same things to use the FSM method of setting the ride height on the front suspension. I understand their reference points and such, but I knew there had to be something better and easier for people who did not want to do all of these things.

Seems like that the flat spot on the bottom of the lower control arm should be reasonably parallel to the road surface when things are "close"? In order to check the side-to-side level, look at the space between the lower control arm bumper and where it contacts the stub frame. Rather than a ruler or tape measure, you can use your fingers (side by side) and visually look at the gap between the bumper and frame item. Then in looking at that gap, you can also check the gap with finger movement, side to side, to "feel" the gap, too. Of course, for this to work, the bumpers need to be in good condition and the same height on each side of the car.

I know that when the cars were new, many dealership people had their yardsticks to measure the height of the wheel opening sheet metal/moldings. I never did like that as those measurements can vary, even side to side, due to the amount of adjustability in how the sheet metal is attached to the body. Things can look "right" and still be toward one end of the spec or the other.

Then I realized that the BEST way to do the deal, even without the FSM and its numbers, is visually. How so? With the car sitting on level ground/surface, the ROCKER PANEL of the car should be sitting level and parallel to the road/ground surface. When the imaginary line extended from either the rocker panel moldings or the bottom of the rocker panel themselves, crosses the center of the wheel/hub cap/wheel cover, it should cross both the front and rear items in the same place. For a reference point, look at the pictures (not drawn art) in the sales brochures to get an idea of how things should look.

Why the rocker panel? When the body structure's metal is laid out, the rocker panel is one of the foundation pieces that everything else is attached/welded to. It HAS to be correct or the rest of the items will not be in-spec, to me.

One disadvantage to my shadetree method is that ALL FOUR TIRES must be of the same size and/or diameter. Of course, too, tire pressures need to be approximately the same.

Understand, also, that the pre-load on the torsion bars will affect the spring rate of the bars. More pre-load = stiffer and will raise the front end above specs.

Less pre-load = softer and will lower the front end below specs. In this mode, the softer spring can allow the front suspension to bottom out easier and more (less distance between the lower control arm bumper and its contact point on the stub frame). More of the dreaded "GM Float", too! Control and safety on a washboard or rough road surface can be compromised, too. More lean in the corners, rather than being more flat (like it should be). Plus, unless the front end is not re-aligned when this is done, the tires can be more into negative camber and more inner-rib tire wear.

As mentioned above, on ANY new bushings in the front suspension, consider the first adjustments the PRELIMINARY adjustments. Get it close, but then re-check after 500-1000 miles to get to the final adjustment, for the reasons stated. Also do the factory-recommended "bounces" of the suspension before any checks or adjustments.

Sorry for the length, but it takes more words to describe the simpler procedures than to put them into action. Plus the reasoning behind getting the desired end results.

Enjoy!
CBODY67
 
Hers a few profile pics of my 69 Fury , it’s 26 9/16 high to the bottom of the trim . The tires have 33psi .
IMG_0648.jpeg
IMG_0651.jpeg
IMG_5916.jpeg
IMG_5815.jpeg
IMG_5726.jpeg
IMG_8206.jpeg
IMG_0417.jpeg
IMG_0422.jpeg
IMG_0420.jpeg
 
Different size tires will change the measurement to the fender, so will rear suspension height, or amout of weight inside car or fuel tank.

Make sure the upper and lower control, arm bolts are loosened so the height change doesn't stress the bushings. Tighten those bolts when car is on the ground and height is where you want it.

Yes it can change after driving, normal to readjust later.
 
Make sure the upper and lower control, arm bolts are loosened so the height change doesn't stress the bushings. Tighten those bolts when car is on the ground and height is where you want it.
^This^
 
Far from expert on this but agree with Old Man on couple things.....cars look better than they did when rolling off the Hamtramck line.....if I spelled it right. Also agree on ride height. I have done some work on mine, but not all, and have adjusted several times. My goal is as said, to get the rockers level. When young, my 57 convert was jacked up, but not now. Ride height will change suspension ride and handling a bit, and can get extreme, but, also want to note that the spring rate is the rate. And, when loaded, they have a force on them that creates a torsion torque. But, changing the position does not affect rate, only position....until you get extreme. The weight and the spring remain pretty much the same thruout our adjustments, meaning that the car weight on the spring is the same, as is the effect of load from bumps and so on. Raising or lowering does not affect the spring itself, just the position and geometry of suspension and steering. What is nice, is that once you get the look you like, then measure both sides at the well trim. Do wish I had the energy to pull the control arms for new bushings....hmmm.
 
Back
Top