Suspension and front alignment

There are a few drawbacks in Destiny's suspension which have bothered me a while and needed to be reviewed. While the rear suspension with original leafs felt too soft , the front of the car vice versa felt too stiff, with the newly installed Kyb Gas-A-Just shocks. When the rear seat was occupied by my daughters the combination felt unbalanced on the road with the rear hanging even lower.

My thoughts about the ride height were contradictory. On the other hand I'd like to lower the stance and on the other I wanted it to stay up. So I would not mind a 1" lowering suspension, if the suspension would be able to bear the weight.

A couple of words about the KYB Gas-A-Justs which despite their confusing name, are not adjustable. What they are is stiff gas shocks which means that you need a lot of force to push them in. And that means they are good for rough driving. That also means that normal cruising on cobble stone street is not the most comfortable experience. If the shocks do not flex, something else in the car will, causing rattle and shake.

A fellow on FMOC happened to have a set of 1" lowering rear springs and a pair of 1" lowering front coils for 100 EUR when I was making a plan for my suspension update. The price seemed reasonable so I bought them. Though, I decided to replace the rear leafs first and then, after seeing the effect, decide what would be the cure for the front. I also placed an order for softer oil/gas KYB Excel-G shocks (formerly known as KYB GR2) for the front. To start with the project I measured the ride height on all corners from ground via wheel center to top of wheel-flare.

Newly sandblasted pair of 1" lowering
sets next to old stock leaf springs.

After painting the leaves and adding some grease and anti-squeak pads, I clamped them the leaves together and bolted them in. Then I took the measures of ride height which showed that the expected 1" lowering had turned out to be only one centimeter  lowering with the new measure being 66 cm.

Next phase was to test the carrying capacity. By asking my wife and daughters to step in, I repeated the earlier measurements of the ride height with load (sorry, no pictures of this), which resulted that the rear sits 1 cm higher with load than earlier. Test approved.

As the lowering of the rear was less than expected, I only replaced the front shocks, instead of replacing or cutting the coils. After this was done and the car stood on blocks of wood I carried out a DIY toe-in and camber measurement.
 

A variety of KYB shocks for early Mustangs

I made a couple of 4-lug modifications to aluminium bars which I borrowed from a friend of mine. Then they were bolted against the brake drums and attached with two measures after the steering was centered.

And the measures were read on the other side. There was 9 mm difference between front and rear which means that the toe-in is 4.5mm (0.43 degrees). The specs for toe-in are  (min,optimum,max) 1/8"-1/4"-3/8" so mine was near to max. I decided to reduce the toe-in to 3 mm total, which called for turning the tie-rod adjustment sleeves about one full turn altogether.




I had unnecessary big 9mm total toe in within 600mm

Many sources say that front alignment should start by measuring and setting the caster. As that is difficult to d-i-y, and my only target was to see whether we're in the range, I skipped the caster and measured camber by the following methods.

The ruler placed vertical against the drum

A bubble gauge 

With the bubble in the middle measure the
gap on the upper end

I repeated the measurement on both sides of the wheel bearing cap, recorded the average and moved on to the other side. Averages were 11.5 driver side and 7.5 passenger side. I placed the numbers in a trigonometric formula and had my camber in degrees. Mine fell withing the acceptable range and with acceptable difference between each other.

I also paid some time cleaning and painting my rims and had the tires balanced in a local tire shop. Then the tires were bolted in and Destiny was dropped on the floor. Ride height front showed 66.8 cm, which is 1 cm less than with Gas-A-Justs and about 1 cm higher that the rear. So Destiny goes slightly nose-up as these ladies used to when they left the assembly line.

 

I also found a date stamp 047 on the tires which means that this set of GoodYear Spectra M+S's left the factory on the fourth week of 1997.  I may have to consider replacing them after a few seasons.  

 

The test drive proved that Excel-Gs were a good choice for my purposes. Small humps and holes were not felt like with Gas-A-Justs and the overall driving experience was smoother and more comfortable.

Thus the new paint on rims , I'll install the hub caps back.