[Heatwave]

I have a 1969 GTO Convertible with a 200 R4 trans and a 3.55 posi rear. I had a previous owner’s suspension springs that had been “cut” years ago. The car rode too low and scraped too many driveways. So I replaced the “cut” springs with a set of generic springs that unfortunately left the car 2 inches higher than the oem spec height of 9.5” front and 9.0” rear.

So after waiting a few years to see if the springs would eventually settle lower, it was still too high. I decided to go to Ames for the appropriate springs and sure enough, after install the Ames springs, the car looks spot on. The ride height is now 9.25” front and 9.25” rear with 15” wheels and 235/60R15 Goodrich T/As.

I also got motivated to improve the steering which was ok but wandered alot at highway speeds. So I decided to tackle replacing the original steering box myself. My steering was 3 3/4 turns from stop to stop. I decided I wanted a quicker ratio. I replaced the existing power steering gearbox with a Cardone unit (27-6509, $159 at my local auto parts with my old unit turned in as a corej. This is a quick ratio unit that resulted in 2 3/4 turns from stop to stop. Very nice improvement.

Once I got into the project I found the rag joint coupler splines to be very worn out which may have been contributing to the sloppy steering. So I replaced the rag joint coupler with a Lares 201 coupler ($32 at my local part store). This coupler has the 31 splines plus flat spot to match the shaft on the Cardone unit for a 1969 GTO.

I clocked the new gearbox by rotating the shaft to full right stop. Placed a white mark on the gear case aligned with a white mark on the pitman arm shaft. Then rotated the steering shaft to the full left stop and placed a white mark on the gearbox case that aligned to the mark on the pitman shaft. Then turned the steering shaft back just less than 1 1/2 turns and marked the case so I would know exactly where the center point was on the pitman arm shaft.

The car drove perfectly straight with the old gear box and I wanted to make sure the new gearbox was installed in the same position. I removed the old gearbox with the steering wheel centered and tires facing straight forward. This was a relatively easy garage swap out. The rag joint coupler nut was torqued to 30ftlb. The 3 gearbox mounting bolts were torqued to 75ftlbs. And the pitman nut was torqued to 140ftlbs on reinstall.

Results: the car now steers and handles terrific. Before it was floaty and wandered on the highway. Very vague steering with “one finger” power steering. More like a Cadillac than a muscle car. With the new gearbox unit, my turning radius is slightly better. Most importantly the steering is much tighter and more controlled with a much faster response. It's no longer “one finger” power steering but that is a good thing. My 1969 GTO steering LOOKS stock but feels pretty damn close to the steering of a modern car.

The combination of oem spec suspension springs and this improved quick ratio steering was a terrific upgrade. Its clearly not a "coil-over" modern suspension but it now feels and rides pretty close to a modern car from my perspective. I thought I would share my experience with this upgrade in case anyone else thinks their 50yr old steering and handling could use some freshening up.

[kk68]

Thanks for the info. Sounds like some great but inexpensive upgrades. Love your car, looks awesome, perfect stance.

[roger1]

Thanks for posting all that info. Did you get all 4 springs from Ames? And, what shocks are you using?

[Heatwave]

Originally Posted by roger1

Thanks for posting all that info. Did you get all 4 springs from Ames? And, what shocks are you using?

All 4 springs are from Ames for a 1969 Convertible GTO w/ AC. The shocks are basic Monroe OE spectrum replacement shocks.

[roger1]

I think you would notice a better ride and road control if you switched to a mono-tube designed shock. Mono-tube are superior to a twin tube design which I'm pretty sure are what the OE Spectrum shocks are.
Least expensive mono-tube shocks are the KYB Gas-A-Just. Quite a step up in price to go to any other brands of mono-tube brands such as Bilsteins.
I put a set of the KYB on my El Camino and was so happy with them, I just bought a set to put on my GTO.