HI All, I am in need of some help here... I need to find the right disc brake choice for this setup. Getting ready to start putting this one together, and figured I would start up front and work my way back... can someone please identify what axle this is, and what you recommend for a disc brake setup? The previous owner said maybe a model a axle, and a mustang 2 disc brake setup would work?
I think it's a 39- 41 Ford axle + wishbones with perch cut off and welded on top. Don't know anything about disc brakes, though.
I am seeing several issues that need to be addressed, aside from suicidally not having front brakes. I cannot see the bolts that retain the kingpins. They also act as the steering stops. If you drop a kingpin, you're dead. The tie rod end is out front. There will be no way to get the Ackerman angle set properly. This will cause the outer tire to not steer, but skid in a corner. If the steering stops are indeed missing. your steering can fold in, in an unrecoverable fashion, on a hard corner. It appears that there is no engine in the chassis, yet the spring shackles are not under tension as they should be. Set up this way, you will have chassis roll in corners, strange handling and steering. The drag link is drastically out of proper alignment. It appears to go uphill as it goes to the rear. Also, the pitman arm appears to go up. With this arrangement, you are absolutely guaranteed to have dangerous bump-steer. There are no shocks. They are not optional. One of the clamp bolts on your tie rod is missing.
I am replacing all of the tie rod ends and heims. As for the kingpins i will have to get that looked at. And the steering box is situated where the pitman are moves forward and aft down the frame..... dont now how i would fix that... tie rod is usually out front on a suicide front suspension.. how would they get around the angle problem you are stating? Also will have to see whats up with the spring shackles.. thanks for pointing these things
If I had to suggest a disc brake setup I would say that Hurst Airheart discs are the real deal. These days they are called Airheart, Hurst is no longer involved. A mustang II setup is not going to be a bolt on and if I was going with floaters I would not use the ford caliper I would use a GM Metric.
Find this hole in your axle. There is one on each side: There should be something in it. It is a wedge-shaped bolt (with no head). That locks the kingpin into the bore in the axle. Look at the opposite side and you should see a nut that looks like this: These are your steering stops. Not having them brings up risks I will detail below. Your steering box needs to be moved, at minimum, possibly replaced with a different one. Where it is right now is not relevant. It is in the wrong place, and most likely the completely wrong steering box for the job. All suicide front ends have the Ackerman angle issue. The only thing you can for sure that do is heat and bend the the steering arms out until they, and the tie rod ends almost hit the backing plates, then install a longer tie rod. Either that, or totally re-do the front suspension. See here two imaginary lines traveling through the tie-rod pivots, through the kingpin pivots, and crossing in the center of the rear axle: (Never mind the 4x4 stuff, same function.) You need to get as close to this as you can, if you want to safely keep the suicide front end (they are not called suicide for nothing. Ackerman angle allows each front tire to travel in a different arc when you are cornering. Since it is referenced to wheelbase, each vehicle setup is different. You will see that the inside wheel is turned in farther than the outside one: That is because it needs to turn in a smaller arc than the outside one. You will also note that this is a tie rod behind setup. Also note the angle between the steering arm and the tie rod on the inside wheel. You will see that it is approaching straight. (180-degrees). That arrangement on your setup will be the outside wheel going around the same corner, as your tie rod is out front. As you are set up now, your outside wheel will be tuned in more than your inside wheel. This causes two things, first, it will cause the outer tire to skid in a corner. Try to imagine steering with just one tire. Your car will push to the outside of the corner, or off the road. Second, while your car is pushing instead of turning, you will instinctively turn the steering wheel more. This risks tucking the tire past the point-of-no-return in regards to the tie rod angle (remember that angle above, approaching 180-degrees). Once the tire is tucked (pushed past the point where road-force overcomes your steering force through the wheel), you will NOT be able to un-tuck it with the steering wheel. You will have to stand on the brakes and pray you don't spin, flip, of otherwise smash into something. This is 1000x the case if your steering stops are missing. If your thumbs are wrapped around the steering wheel when the outer wheel tucks, you may very well break one or both of them. I have done this, in a 4x4 rig. Both hands. Very painful.
I'd heat those spindle arms and bend them down as you would for a drop axle and put that tie rod behind the axle where it belongs. There's no need for it to be out front on that car.
I agree.^^^ and still use the gimp's diagram to set the angle properly. The side steer setup (with a drag link that follows the frame) is a common setup, and I am not seeing a problem with the shackles other then the fact that they are hung off the radius rod and not off the common spring perch bolts. I would suggest beefing the radius rod where the spring perch is welded on though. @STUNNED MULLET The old heap is a little cobbled now but it can be uncobbled and I am sure that you can do it if you just try.
The problem with the spring is that it is supposed to be installed under tension, using a spreader. The shackles should be dead level with the chassis unloaded (no engine, etc). As pictured, there is no tension on the spring. This prevents not only proper spring function (shackles may bottom out, or worse), it also defeats the function of locating the chassis over the axle (strange handling, steering, and body roll. As for the steering, the geometry is totally wrong. Please post a side view picture of the steering and suspension. I will illustrate what is wrong.
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