New to the forums here and am hoping that a few of you could offer some advice.
Here is the deal. I have a 69 fastback. Here is a list of everything I have replaced on the front end. New lower control arms, rebuilt uppers (ball joints and shafts-I tack welded the caps on), Shelby drop, poly bushings in the original spring perches, new outer and inner tie rods, idler arm, 1 inch front sway bar, new strut rod bushings, KYB shocks, front wheel bearings and new lowering springs.The ram and pump are still original but nothing leaks. On the rear I have new springs with poly bushings and heavy duty shackles. I also have a set of Global West sub frame connectors. The rear was rebuilt with all new bearings, posi and ring and pinion.
I am the third owner of the car but I really have no way to know how many miles are on it. The odometer says 89,000 currently. So I'm positive its at least 189,000 maybe even 289,000.
I've had it aligned twice and the second time ( a different shop) they got the specs pretty good. I don't remember the actual numbers but I finally have some return to center and it goes pretty straight down the road. Tire wear is good as well.
However this thing is absolutely scary over 80mph. Example down shifting to 3rd and revving the motor up to over 4k while maneuvering out of my lane into the oncoming one and back into mine is enough to give you a heart attack. I rebuilt my power steering control valve thinking this would help. It didn't make any difference. What I did notice when I had it apart is that the spool valve to me seemed messed up a little.
Its kind of difficult to explain but I will have to because I didn't take pictures of it. It looks as though you took a grinding bit and put a 45% bevel on part of the spool valve. This happened in 3 areas, the inside of both the large outer portions and both sides of the large middle section. Each section is only about 1/2 an inch long and are all in line with each other. The spool valve other then the edges being messed up looked okay. Meaning no grooving or pitting. Same with the housing. The bore looked good.
The best way to explain how it drives when your going from one direction to another under high load is that it has a huge dead spot and you actually have to over steer the car to go where you want it to. Once it does start to head in the direction you want then it quickly goes to much in that direction and you have to over correct the other way just to keep it on the road.
Another way to describe is like the ram is completely worn out and when pressure gets high there is bleed over from one side (that would make the car turn left) to the other side (to make the car turn right). Who knows, maybe its a combination of both. I can say that anything below 40 mph at low RPM's it drives pretty good.
I do not have any idea how these things drove new. So I do not know if its even worth spending the money to replace the factory stuff (control valve, ram and power steering pump) with new units that from what I understand are made over seas, get rebuilt units, convert it to manual steering (which is another issue) or just replace the whole system with a rack and pinion. I have driven a 69 with the flaming river power rack and it was great but the reduced turning radius was a real PITA! I don't like the decreased turning radius. Being a daily driver having to do a three point turn when its able to do a U turn (with the factory steering) just stinks.
The Borgeson box seemed like a good option but I have read quite a bit about people complaining of a lack of feedback and the return to center being almost non existent. So I have concerns with going that route. Plus my car is low and the longer sector shaft has me worried some.
I know that this is an entirely different steering system but I had a 67 F100 that after I replaced the I beam pivot bushings, king pins and adjusted the steering box drove like a dream! No play and very responsive. But I do know it had an integral PS box. I can't imagine that the factory system on the early mustangs was all that bad when working properly?
I have made sure that there is not something else wrong like cracked shock tower, frame rail, or that anything is loose or moving around. Because honestly that is what it feels like. I caught a pot hole with the idler arm and it tore the frame rail pretty bad. I did a very sturdy fix on that. But it still dives the same before and after that happened.
Kind of at a loss as to what direction to head in right now with it because funds are the main issue. I would like to keep power steering if possible. If replacing the ram, control valve and pump will take care of it, great! But if purchasing a manual steering adapter is the only way that's going to fix it then I guess that is what I will have to settle for.
The cam is going flat and I am going to change it out for a roller. This $$$ was going to be spent on the steering but obviously if the motors getting pumped full of metal then there is not point in fixing the steering at this time.
I kind of feel it might be a catch 22 kind of deal. As I mentioned I have no idea how these things drive when everything is working properly. I don't want to flush $600 dollars down the drain then end up with something that still makes you pucker and white knuckled every time you do some spirited driving. This is why I mentioned just going manual until I can afford something like a Steeroids kit. Without a frame of reference its really difficult to make a decision.