Home built rack and pinion+ coilover build.

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The shock mount will definitely get braced. At this point, it looks like the shock upper bolt will go through the portion of the shock tower brace where it is bent almost horizontal. Without looking too close just yet I figure some bracing going down to the frame rail will get the job done. I just have to wait till I can look at what room I have to work with . I have Dillenger upper triangular control arms on the Dart already, needed to clear the 6.3 offset wheels. That may limit available space for bracing.
 
Here is a start on making a new end for the tie rod assembly using Mustang II outer tie rods, which have the same taper as the Mopar ends. Purchase a length ($45!) of 9/16 x 18 threaded rod in M7 grade (strong) . About four inches will allow plenty of adjustment. A piece of 3/4 diameter thick wall tube about two inches long will work for welding the threaded rod to, and will slide over the shaft of the pinto rack that isn't threaded with a little work. A 35/64 bit will drill the right sized hole, or close. I found one at WW Graingers for $22 including tax. A little sanding on the tie rod shaft will allow the pieces to slide together nicely. To weld the threaded rod to the tube, sand off the threads on a belt sander till you can tap it into the tube a bit. All you need is to make it stay in line while you weld it together. Once you get the threaded rod welded all the way around, run the nut all the way down and weld that to the tube as well. With both the inner weld and the outer weld, It ought to be stronger than you will ever need it to be.
I measured it out, but it looks like I will have to shorten the shaft on the rack to narrow up the whole assembly some. The tubes have just a spot weld holding them till I see exactly what I need to do to make it fit. I have to make the motor mounts next, to make sure I don't get things too close together. I want at least 1/8 inch clearance to the pan if I need to space the rack up for alignment purposes. Then I can start making the steering arms. They will be cut out of 3/8 x 4 inch plate, and will bolt to the outside of the balljoints. I plan on welding the old arms onto the new plates to mate the tie rod ends and steering arms. I will post pics as soon as I get a good start on them.
 

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Good to know about the taper.

I used to HATE Moog catalogs, which instead of listing taper in angle or such, was in a way that made comparisons very difficult, other than just guessing and opening boxes.

This was back when many "of us" were screwing with PS in Jeeps, etc.

On a side note, the older Broncos used to have two? known useable boxes, one out of some 62? Buick, and T bird. At that time the only source for an actual Bronco box was the Dealer which was over 400 bucks, I think, and that was the early 70's

Anyhow, a friend of mine who is a great fabricator, has a muffler shop then, and a Bronco for snow, etc.

One night after work two of us were gonna get Dean and have coffee, and here's his Bronco coming down off the lift.

He'd put a mopar box in the Bronco!!!!!

I said, You ARE sure this turns the right direction????

"Funny look" comes over his face, and sure enough, 'es backwards!!!!
 
how did you do your lca I was thinking of taping and threding with a grade 8 bolt and washer.to hold it there and I seen one on here that the torshtion bar was just taken off with nothing hold it! but the man said he's raced it like that for years. with no trouble..I want to do something to get rid of the bar cuz I don't like using fender well headers.the last duster I did we set the motor back 1inch to put Bbody headers on.worked good but had to put small dent in 2 tubes:violent1: and didn't like doing that.not that I don't like the torsion bar set up I think its the best thing since sliced bread.but they do get in the way.......Artie
 
I am going to run the lower control arm just like the factory did. For the limited abuse this car will see, I don't think there will be any problem. If you think about it, the torsion bars may not have given much lateral support anyway. There is clearance in the T bar sockets, so the arm (pin) could move some anyway if it were weak. Also consider that the main support for the front is now the upper shock mounts, rather than the torsion bars. So that takes a lot of the load off the inner end of the lower control arm.
 
I am going to run the lower control arm just like the factory did. For the limited abuse this car will see, I don't think there will be any problem. If you think about it, the torsion bars may not have given much lateral support anyway. There is clearance in the T bar sockets, so the arm (pin) could move some anyway if it were weak. Also consider that the main support for the front is now the upper shock mounts, rather than the torsion bars. So that takes a lot of the load off the inner end of the lower control arm.
ya I agree but its the idea of seeing it there like that..lol if ya know what I mean......Artie
 
With out the Torsion Bar how do you plan on retaining the LCA?
Bob
 
I had some time to work on the conversion today, hear are a couple of photos of what I am up to. You can see the T shaped piece of angle iron I drape the tape measures across. The center tape is for setting the height for each measurement, and the T bar must be leveled every time before readings to get accurate results. The numbers need to be compared for toe in, toe out, and the total distance will change due to the arc of the suspension, even if the toe does not. So check both sides and record the difference at each inch of travel. I start where I figure it will be set for ride height, or about two inches of spindle travel from the bottom bump stop. I can then set the toe at zero at that point, to make the math simpler.
I have been doing the alignment on the front of my 8 second Dart for years, never had it on an alignment rack. It handles very well at 150 mph, so I am confident this is an ok system to use to set up a front end. On the race car, I use two pieces of 1/2 inch square tubing, 28 inches long, each strapped to the outside of the front tires six inches off the ground, leveled. I double check my numbers by moving the metal tubes a couple of times to make sure the measurements are consistent, and not on a high or low spot on the tire, which would skew the readings and throw the alignment off. Here it was easier to just make some T bars. For the full alignment, I bought a bolt on tool that has bubbles for setting caster and camber, after which I can then set the toe.
In the picture you can see the tape measure ends are duct taped to the other side of the hoist. I use one inch increments to graph out the toe in / toe out pattern, then make adjustments. Watch out for things that can mess up the measurements. Slack in the suspension, tapes not equally tight, anything that will allow a variance. I double checked my numbers a couple of times, and sure enough, found something loose.
If you look at the steering arm, it is just a throw together deal to get the dimensions of the steering arms. Once I find out where the tie rod end goes in height and length, and figure out the proper tie rod length, I can then fabricate the arms. I may make them adjustable by using a bolt together design, not sure yet. It would really simplify any needed adjustments down the road.
In the bottom picture you can see the 5/16 bolt through the stub of the old steering arm, which is bolted to the new plates that are in turn bolted to the back side of the spindle.
 

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With out the Torsion Bar how do you plan on retaining the LCA?
Bob
You got me to thinking about how that is going to work, and I came up with something that should work. Before I rebuilt the lower control arms, I drilled and tapped the pins that go in the K frame for a 3/8 bolt so I can stop the lca from ever sliding off the pin, if that is even possible with those pressed on bonded bushings. This bolt will need a large washer, and some way of keeping the bolt from backing out of the pin due to the LCA rubbing against the washer. Maybe a piece of threaded rod rather than a bolt, with a nut locked against the pin, then a washer against the T bar socket, and two nuts torqued against each other out side of that. Kinda complicated, but that is what came to mind at the moment. Anybody have a better idea, please reply.
 
If you mocked that up I would really like to see a picture of it. A few years ago I was looking into a Coil-over conversion using tubular upper and (maybe) lower A arms w/a stock manual steering box for my '65 Valiant and the bolt/washer retainer was suggested at that time.
You might look at www.bobsprofab.com for his upper shock mount brace as a design reference.
Bob
 
So this is just meant for the staight aways? And not good for a street car.
This setup is for my street car, and it will be plenty strong enough. It uses all streetable components, like tie rod ends, pinto rack, stock control arms. No rod ends to wear out prematurely.
 
Some more pictures. I got the bump steer within reason for most of the travel. The unequal length A arms create some dificultys, so the Toe goes in at top and bottom of travel, but is very good in the middle. It took a long time to get this far, mainly because I missed a variable while testing and it threw my numbers all over the place and cost a lot of time. The measurements need to be made with a jack pushing up on the bottom of the control arm to simulate a load from where it will be during use. Trying to lift the suspension by the spindle allows the slop in the lower ball joints to move around. Also it is a good idea to measure where the bump stops hit, and don't take any readings with the suspension touching either.
The end result had me scratching my head to figure out how to move the brake rotors out far enough. I looked at my Wilwood kit and by flipping the brackets for the calipers around, and juggling the way the rotors attach to the hub I can move them out 1.2 inches, VERY close to the 18 inch wheels I have with 6.3 inch back space. I also have a 3/16 wheel spacer in between the wheel and hub, which will be needed to clear the calipers in their new location. The tie rod end needs to be WAY out there, and the move of the rotors will allow a good tie rod length for proper bump steer. I would like to go longer on the tie rod length, but it just isn't possible to put it out that far. If the wheel base is wider on the later A bodys, they will have a much easier time of it. Same for a B body or E body car. With the narrow A body wheel base, the end result is the outer tie rod ends need to be farther out than where they should be for correct ackerman angle. It isn't rel bad, just more than I would like to see.
To be clear on this- if you can't or don't want to move the brake parts around, there is only one solution. The lower control arm must be shorter. That would then require a whole different K frame , mounting position, and loss of the use of stock parts for most of this conversion. EDIT; You could run a narrower rack, and it would work. But Ackerman will probably be off some due to the lack of room for tie rod length.
So a quick recap- This conversion will need disc brakes that have a very shallow offset from the hub to clear the tie rod position. The wheels will probably need to be seventeen inchers or bigger to clear the tie rod ends. Here are a couple of photos of my stuff for tonight. If you look at the last photo, consider how far out board the tie rod is in relation to where the bolt heads for the lower ball joints are. The only way to keep the bump steer from going crazy is to have either that tie rod end way out there, or buy a three or four inch shorter rack and pinion setup.
 

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A rack that is four inches narrower than a stock Pinto or Mustang II rack will most likely get the bump steer very close at the outer ends of travel, and would move that outer tie rod end in far enough to clear the rotor on a standard Wilwood setup. I don't know how much offset difference there is between the Wilwood kit and a factory A body disc brake kit. If someone could measure from the inner rotor surface to the center of the lower ball joint grease zerk, we could figure it out.
I do know that the inner tie rod would need to be within a 1/4 inch of the Wilwood rotors with a four inch narrower rack. The stock \Pinto/Mustang rack has an inner center to center length of 25 inches.
 
Hope you keep this thread updated. If you can, I'd like to more on how you determined "no bump steer." I'm guessing? the rack is considerably ahead? of where the original center link was?

With this being a front steer setup, the tie rods move to the front. The width of the inner ends of the Rack will determine where to put the outer tie rod ends to achieve good bump steer, and as I posted above, with the unequal upper/lower control arms, the needed tie rod length gets real long which puts the ends way out board of where I would like. That is why I would go with a four inch narrower rack to start with. It would also place everything closer to proper Ackerman angle, which is the outer tie rod, lower ball joint, and rear axle center line all on a straight line.
 
With this being a front steer setup, the tie rods move to the front. The width of the inner ends of the Rack will determine where to put the outer tie rod ends to achieve good bump steer, and as I posted above, with the unequal upper/lower control arms, the needed tie rod length gets real long which puts the ends way out board of where I would like. That is why I would go with a four inch narrower rack to start with. It would also place everything closer to proper Ackerman angle, which is the outer tie rod, lower ball joint, and rear axle center line all on a straight line.
I think that bump steer thing is bull ****...Now If you were going to road race it YA I would be concerned..and I know that 'CRACKEDBACK' will confirm this hopefully he will chime in too back me up.............Artie :coffee2:
 
I am going to run the lower control arm just like the factory did. For the limited abuse this car will see, I don't think there will be any problem. If you think about it, the torsion bars may not have given much lateral support anyway. There is clearance in the T bar sockets, so the arm (pin) could move some anyway if it were weak. Also consider that the main support for the front is now the upper shock mounts, rather than the torsion bars. So that takes a lot of the load off the inner end of the lower control arm.
well actually the torsion bar does with the amount of pressure that's on that bar I wouldn't be afraid to run it without the nut on the LCA even if the pressure was off of it I have never taken one out that I didn't have to beat the hell out of or rowend the clamp or tool I guess I should say to do it..and without the bar there is no way in hell the LCA can come out with the strut rod in place. and if it did come out or move you should no it long before it did.by the way the thing is stering.think about it.with the bar out the strut rod off the bushing is whats holding it in.and if that's good or new well you tell me.thats wy Im going to drill and tap it for a bolt evon if its only 5/16 just for the knowing its there..I hope I expland my thuts right??Im better at drawing pichures......Artie
 
Artie, I agree the retaining bolt that I plan to install at the inner end of the lower control arm is overkill. But I am a nervous type. So,,,,,,,,,, As far as loads go, the load on the inner end of the lower control arm no longer has to resist the spring pressure of the T bars. The spring load is now at the shock mount on the lower control arm which is closer to the wheel so the load is cut in half or more. The only other loads are cornering forces, and bumps.
EDIT;
I found custom length racks available from Unisteer. The Pinto manual rack custom length is 399
 
I hear ya on the safety.For a rack I got on Ebay under used racing parts typed in stock cars WOW gooooooood buys and that's where I got my rack (sweet which is a top of the game name) its 9 inches long and is lock to lock 1/2 turn they have them different ratios you'll have to read the specs on them.and the 5$ price tag was good to.most of those top name guys only run them for One racing season or if there in a crash which hardly ever herts them.you can get them with power to which most of them are running now.and the power ones only take 2 hp to run them and take up very little space under the hood those are usually sold as a unit with the braided line and all the bracketry.and the rads are cheap to I bought a 4 core with oil cooler that slides between the rales of a duster for 50$ and looks like new.there usually 50 to 150$ and I hate paying for the same dam thing from the speed ?? shops.for drag racing parts if I don't have to.because they are usually twice the price and I figure if they're safe enough for daytona at 200 mph or on dirt that's so bad you can hardly walk across they will take anything I have to throw at them! hope this is a help..... Artie :coffee2:
 
Latest update; I tried to swap parts around on the Wilwood discs, and came up short on the needed space for the tie rod location. By flipping parts around I could move the disc out .62 inches, or 1.25 inches. Each will require custom made brake caliper brackets, which could also be built with the steering arm on them. The .62 inch move doesn't allow for proper tie rod length, but the 1.25 inch move might. Moving the brake disc 1.25 inches closer to the wheel will require wheel spacers (1/2 inch to 3/4 inch?), and longer wheel studs. That sounds like a lot of offset, but this front suspension was designed with a lot less back space, so it works out.

It looks like this may force me into a custom length rack. I have been working with one side of the suspension so far. To get the most accurate final dimensions, I will start working with both sides, now that I have a baseline of sorts. At this point, the final width of a custom rack needs to be four inches narrower than a stock Pinto or Mustang rack. The stock units come twenty five inches inside c/c, looks like I need about twenty one c/c. I will try and get some final numbers posted soon.
 
...........so greg, could u not shorten the inner tie rod end and maybe the threaded rod to get ur needed distance and still have enough adjustability, or am I way off.........kim...
 
Kim, the problem is the length of the Mopar lower control arm demands a long tie rod to keep the wheels parallel throughout travel. (The original suspension that the Pinto had had short lower control arms, so the overall width was narrower in stock use.)
If the tie rod is too short, the wheels pull in whenever the suspension moves either up or down. If it is too long, they will toe out. So the problem then becomes the distance between the inner tie rod ends. On the Mopar early A, that length needs to be about 21 inch. I spotted a reference on another web site to a shop called THE RACE SHOP in Seymour Wis. They have narrowed racks in the past and I am going to see if they still do. The price back in 2008 was $150, hope it is still under $200.
By shortening the rack the exact needed amount, then everything SHOULD line up. I am still hoping someone will post the specs for stock disc brake rotor to Zerk length, which will tell me how well this whole deal will fit with a conversion to 73 and up factory discs, which a lot of guys would like to do.
 
Greg;
I have the '73-up disc brake conversion on my otherwise stock suspension '65 Valiant. What exactly do you need in the way of a measurement?
Bob
 
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