6T6coupe said:
The biggest problem with the Bendix style linkage-assist power steering system is the slop that is designed in. The pitman arm has to physically move the ball stud in order to operate the valve before the steering linkage even begins to move. That big steering wheel movement and lack of on-center feel before anything happens is a design feature. Toss in all the leaks and you have a system that everyone loves to hate.
Rebuilding/replacing the valve, installing a new steering box, quickening the steering, and/or replacing the entire linkage will help eliminate the play caused by normal wear, but will never, ever eliminate that built in movement that has to occur before the assist kicks in.
I understand the system isn't ideal, but ya know, I never thought it was all that bad. I've said this before, and I'll say it again: I've driven cars with integral boxes (including the ever prevalent saginaw), and some have been better in terms of feel and response compared to my stock system, but some have also been worse.
The entire time I drove my Mach daily (my only car for the better part of 6 years), I never found the steering to be troublesome or so vague that I couldn't easily keep the car in its own lane, or point it where I needed to. I also never suffered the tremendous amounts of bump steer I hear everyone complain about (and I was driving the car in Tampa, and anyone who has driven there knows how bad the roads can be, and the damn train tracks every 1/2 mile).
Personally, I just want a system that is
more responsive and has
more feel, 'cause for the most part it seems to function pretty well otherwise.
And while I like the idea of a rack&pinion conversion, there are some serious (to me) drawbacks. Most of all, the loss of turning radius. This may not be a big deal to many, but if you drive your car in a city like Seattle, or SF, or Chicago, and you have to negotiate tight parking lots and parallel park regularly, then you know you can't afford to lose any turning radius.
Another of my big concerns about the rack&pinion conversion is that most (if not all) are proprietary systems. This means if the rack fails, breaks, gets clobbered by something, and has to be replaced, then you have to source another one from TCP, or Flaming River, or Rod&Custom, or whoever. Admittedly there are probably exceptions (I think Randall's rack is a production piece, and he has a cure for the loss of turning radius), but still, if you actually drive your car, and the rack gets fragged in the middle of Nowhere USA, you're in a tough spot to get it repaired. Stock steering parts are available at most regular auto parts stores (especially NAPA), and any two-bit mediocre mechanic (like me) can put it together.