Rack and pinion steering.

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MOPARMAGA

MOPARMAGA

" The other hard member"
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Drag car only guys !
In the spirit of diy, I want to put a rack and pinion system on my dart...out front. I want to make it work and modify my stock k-menber.
I can't afford a nice tubular deal like hdk or I would do it the easy way.
Basically I want to get the drag link out of my oil pan, and drop that weight.
Does anyone know where I can start with the proper fitting rack ?
I have read that maybe a pinto rack would fit but I'm not sure if there's better options.
I'm looking for a manual rack.
Thank you kindly, happy new year!
 
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if you move the rack to the front and away from your pan, you'll need to figure out how to make what you've got front steer off the spindles.
 
I'm sure someone will correct me if I'm wrong; but I seem to remember reading that when it was attempted, swapping the lower ball joints to the other side to make the spindles front steer introduces all kinds of wonky geometry issues and made the car basically undriveable.
Swapping the spindles is one thing, swapping the ball joints w/steering arms is another entirely.
I'll see if I can find the thread(s).
 
Professor Fate said:
I'm sure someone will correct me if I'm wrong; but I seem to remember reading that when it was attempted, swapping the lower ball joints to the other side to make the spindles front steer introduces all kinds of wonky geometry issues and made the car basically undriveable.
Swapping the spindles is one thing, swapping the ball joints w/steering arms is another entirely.
I'll see if I can find the thread(s).
Click to expand...

Swapping the spindles side to side doesn’t change anything other than the position of the brake caliper.

Swapping the lower ball joints puts the steering arm forward, but absolutely hammers the Ackerman for the steering geometry.

It’s been done on some drag only cars that have very little suspension travel, and in that setting it may be tolerable (but not good). On the the street it’s an accident waiting to happen.
 
72bluNblu said:
Swapping the spindles side to side doesn’t change anything other than the position of the brake caliper.

Swapping the lower ball joints puts the steering arm forward, but absolutely hammers the Ackerman for the steering geometry.

It’s been done on some drag only cars that have very little suspension travel, and in that setting it may be tolerable (but not good). On the the street it’s an accident waiting to happen.
Click to expand...
That's what I meant by saying "swapping the spindles is one thing..." Maybe I phrased it badly.
My meaning was that flipping the spindles may be common, but he should realize the same doesn't apply to the balljoint/steering arm.
Heck, now that I tried to find the thread I was thinking of, I found so many saying the same thing that OP should probably just run a search and then hunker down for an evening of reading.
 
72bluNblu said:
Swapping the spindles side to side doesn’t change anything other than the position of the brake caliper.

Swapping the lower ball joints puts the steering arm forward, but absolutely hammers the Ackerman for the steering geometry.

It’s been done on some drag only cars that have very little suspension travel, and in that setting it may be tolerable (but not good). On the the street it’s an accident waiting to happen.
Click to expand...
Race car only. Okay right, swapping lower ball joints.
 
junkyardhero said:
even then, you're still gonna be miles away from the rack pick up unless it's thru the middle of the K
Click to expand...
Yeah that's what I envisioned, I don't care about modifying stuff. I've rebuilt this entire car and only a few things were left factory, front frame rails, most of the firewall, transmission/ torsion bar cross member and factory body parts. Everything else has been redone or modified factory parts like rear frame rails sectioned and moved inboard.
I am basically looking for the correct rack to start with , a cheap one so if it doesn't work I'm not blowing a huge load on nothing.
 
MOPARMAGA said:
Thanks guys for your input, I was really looking for people who have successfully done it themselves.
I've seen in pictures of it being done, hopefully someone who's done it will chime in.
Click to expand...

It was originally done on some of the drag cars back in the late '70's, I forget which class but the caveat was that they were basically lowered onto the bump stops and had almost no useable suspension travel, which limits the impact of the terrible Ackerman angles that are caused by flipping the ball joints to get the front steer.

The steering geometry that results is TERRIBLE. Which is why the rack and pinion conversions that work pretty much all use tubular K members and different spindles. There is no cheap easy way to add a front steer rack on a Mopar with a stock K that doesn't result in abysmal steering geometry. If there was, you'd see it all the time. It was a drag car thing for awhile, but Ackerman is also only an issue when you turn the wheels, so, what you can get away with on a drag only car is significantly different than what you can get away with on a street car.

I'm not sure how many people that have successfully done it are still around. brian6pac did it on one of his drag cars, but he cut and welded the steering arms on the lower ball joints to improve the Ackerman. He's also no longer with us. I took quick look at some of the threads where it was talked about, most of the guys that said they did it haven't been around for years.

Best of luck!
 
I've seen it done. Back in the 70s. On a Demon drag car. It wasn't pretty.

That was over 45 years ago so the main things I remember was that the k-member was cut so the Pinto rack & pinion was mounted through the k-member. It was still forward enough that the tie rod ends angled rearward from the rack. And with the spindles swapped side to side, the steering arm was angled inward toward the front of the car. So, when the car was steered to the right far enough, the left steering arm and tie rod end would end up in a straight line and could go over center. Then when the steering was turned back to the left, the right wheel would go back towards center and the left wheel would be turned right about as far as it could go. Now if you don't turn the steering very much, you may get away with it but it's a really bad idea.
Of course steering to the left would have the same effect the other direction.
 
72bluNblu said:
It was originally done on some of the drag cars back in the late '70's, I forget which class but the caveat was that they were basically lowered onto the bump stops and had almost no useable suspension travel, which limits the impact of the terrible Ackerman angles that are caused by flipping the ball joints to get the front steer.

The steering geometry that results is TERRIBLE. Which is why the rack and pinion conversions that work pretty much all use tubular K members and different spindles. There is no cheap easy way to add a front steer rack on a Mopar with a stock K that doesn't result in abysmal steering geometry. If there was, you'd see it all the time. It was a drag car thing for awhile, but Ackerman is also only an issue when you turn the wheels, so, what you can get away with on a drag only car is significantly different than what you can get away with on a street car.

I'm not sure how many people that have successfully done it are still around. brian6pac did it on one of his drag cars, but he cut and welded the steering arms on the lower ball joints to improve the Ackerman. He's also no longer with us. I took quick look at some of the threads where it was talked about, most of the guys that said they did it haven't been around for years.

Best of luck!
Click to expand...
Thank you sir, I'll take a look at his thread's
 
tinman2 said:
I've seen it done. Back in the 70s. On a Demon drag car. It wasn't pretty.

That was over 45 years ago so the main things I remember was that the k-member was cut so the Pinto rack & pinion was mounted through the k-member. It was still forward enough that the tie rod ends angled rearward from the rack. And with the spindles swapped side to side, the steering arm was angled inward toward the front of the car. So, when the car was steered to the right far enough, the left steering arm and tie rod end would end up in a straight line and could go over center. Then when the steering was turned back to the left, the right wheel would go back towards center and the left wheel would be turned right about as far as it could go. Now if you don't turn the steering very much, you may get away with it but it's a really bad idea.
Of course steering to the left would have the same effect the other direction.
Click to expand...
Sounds slightly dangerous lol
Thank you for your reply.
 
I was going to attempt it years ago with my 70 Dart drag car. I already had a front engine plate and a mid plate. I got a 74 k frame from a six cylinder car, and cut all the engine mounts off it. It had an opening in the front I thought I could mount the pinto style rack and pinion. But I never finished it, I bought a different car, and the Dart is back on the street. From what I recall, going in reverse caused a problem with the toe.
 
MOPARMAGA said:
I don't know if I have short term memory loss or not, I did a search on this subject but wanted to ask or re ask .
In the spirit of diy, I want to put a rack and pinion system on my dart...out front. I want to make it work and modify my stock k-menber.
I can't afford a nice tubular deal like hdk or I would do it the easy way.
Basically I want to get the drag link out of my oil pan, and drop that weight.
Does anyone know where I can start with the proper fitting rack ?
I have read that maybe a pinto rack would fit but I'm not sure if there's better options.
I'm looking for a manual rack.
Thank you kindly, happy new year!
Click to expand...
A couple of things to digest. Unless you move the engine back excessively ( i don't recommend for many reasons) EITHER suspension will compromise the oil pan. Most the weight will be saved in brakes. Also, you can save 10-15# more by eliminating the tbars with a coilover shock. and that'll 'require' a tubular upper for clearance $. The best bang for the buck is cleaning-up the K while reinforcing it after you cut it for a 'good' full oil pan and lighter brakes. If you swapped the spindles you can heat and bend the steering arms outward and I've heard a Dakota rack is closer to the pivot WIDTH for the oem suspension than typical Must2 stuff. I have seen bend arms work properly on a light drag car and have bent the arms myself on a homemade jig. But again that'll take some time engineering all aspects of a functional /safe suspension to include bumpersteer over a good amount of travel (4" MINIMUM) and ackerman and really net you minimal gain other than easier removal of the still compromised pan (now in the front). Personally if you have the time to do this, I'd spend the time doing some easy chassis jobs for customers and make money. Just KISS when it comes to your car IMO.
 
Professor Fate said:
I'm sure someone will correct me if I'm wrong; but I seem to remember reading that when it was attempted, swapping the lower ball joints to the other side to make the spindles front steer introduces all kinds of wonky geometry issues and made the car basically undriveable.
Swapping the spindles is one thing, swapping the ball joints w/steering arms is another entirely.
I'll see if I can find the thread(s).
Click to expand...

I think Uni-steer (or whutever) got sued out of business for trying this.
I have a rack and pinion in my 70 ‘cuda and it’s swell. It is, however, on an Alter-k-tion front suspension.
I also have a Borgeson in the ‘73 Duster. The “feel” between the two is very similar. I’ll put it this way, if you are just wanting r&p only then just get the Borgeson box. IF you want front steer setup (r&p) for the combination of header clearance and steering feel then I would recommend HemiDenny or Alter-k-tion.
There should be a flow chart for when to use certain components. If you deduce that there are multiple features that would benefit you then they are great. If it’s a street car w/ no requirement for 1-7/8” headers then you probably don’t NEED an exotic suspension. If racing and need front steer for headers then exotic could be a benefit, the r&p would be a beneficial addition for that reason.
After doing both, my next build is a wicked 550 hp, 6 speed, 9” floating rear, all the corner carver strengthening and bracing, ….. I am planning for a 20:1 manual box + electronic power steering. My headers are TTI-340’s which fit above rear steering components. You get rid of a v- belt with EPAS too.
I hope this helps. Uni-steer type set ups should be looked down upon, be discredited, and be ever be considered.


Options in order of need (streetcar to race car):
  1. OEM
  2. Fast ratio manual (16:1)
  3. Borgeson
  4. FR manual (20:1) + EPAS
  5. IFS w/r&p IF using 1-7/8”+ header
* 1-4 is using an OE k-frame.


These are my opinions with experience from using these setups. If you can’t land at the right spot after this advice then luck be with you.
 
ValiantS said:
Personally if you have the time to do this, I'd spend the time doing some easy chassis jobs for customers and make money. Just KISS when it comes to your car IMO.
Click to expand...

Personally, if OP has time to do this (and actually considering it) then he should never work on someone else’s car.
Any form of modification to the stock spindle (especially heating and bending) to achieve front steer r&p is slap stupid.

This should be a sticky, a list of boneheaded products and companies that are safety hazards :
  • Uni-steer or anything like it
  • Magnum Force anything
  • …..
There are other goofball products on the market but these above are actual safety hazards.
 
I put a Church Boys Racing r&p conversion kit into my '63 Chevy II a couple of years ago (Covid project...no more Chevys!). Engineered designs are the only way to go but not cheap. I believe the r&p was from Detroit Speed.
 
MOPARMAGA said:
I don't know if I have short term memory loss or not, I did a search on this subject but wanted to ask or re ask .
In the spirit of diy, I want to put a rack and pinion system on my dart...out front. I want to make it work and modify my stock k-menber.
I can't afford a nice tubular deal like hdk or I would do it the easy way.
Basically I want to get the drag link out of my oil pan, and drop that weight.
Does anyone know where I can start with the proper fitting rack ?
I have read that maybe a pinto rack would fit but I'm not sure if there's better options.
I'm looking for a manual rack.
Thank you kindly, happy new year!
Click to expand...


BTDT. You can do it but it’s a lot of work to get it right.
 
I see some are saying that if it is a drag car you may get away with it. Please keep in mind that if you get out of shape and are trying to get back into the groove, you're going to need some of that proper geometry and handling. It will even come into play if you come off the pedal and your out of shape. Just food for thought
 
ValiantS said:
A couple of things to digest. Unless you move the engine back excessively ( i don't recommend for many reasons) EITHER suspension will compromise the oil pan. Most the weight will be saved in brakes. Also, you can save 10-15# more by eliminating the tbars with a coilover shock. and that'll 'require' a tubular upper for clearance $. The best bang for the buck is cleaning-up the K while reinforcing it after you cut it for a 'good' full oil pan and lighter brakes. If you swapped the spindles you can heat and bend the steering arms outward and I've heard a Dakota rack is closer to the pivot WIDTH for the oem suspension than typical Must2 stuff. I have seen bend arms work properly on a light drag car and have bent the arms myself on a homemade jig. But again that'll take some time engineering all aspects of a functional /safe suspension to include bumpersteer over a good amount of travel (4" MINIMUM) and ackerman and really net you minimal gain other than easier removal of the still compromised pan (now in the front). Personally if you have the time to do this, I'd spend the time doing some easy chassis jobs for customers and make money. Just KISS when it comes to your car IMO.
Click to expand...
Thank you Sean for your input. I have strange brakes up front, k member is already good for my 9 qt milodon.
Definitely a lot to consider. At this point I'm just going to table this and finish the rest of the car and get the thing making passes for this season.
go-fish said:
Personally, if OP has time to do this (and actually considering it) then he should never work on someone else’s car.
Any form of modification to the stock spindle (especially heating and bending) to achieve front steer r&p is slap stupid.

This should be a sticky, a list of boneheaded products and companies that are safety hazards :
  • Uni-steer or anything like it
  • Magnum Force anything
  • …..
There are other goofball products on the market but these above are actual safety hazards.
Click to expand...
If I get into it and something doesn't seem right, something doesn't work & 1st of can't be made safe I won't do it.
I would not be making any modifications to a spindle. Although pro stock guys in the 70s drilled the **** out of them.
I have a thread on the car if you want to check it out & see if I should or shouldn't work on someone else's car.
 
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I've seen people shorten racks, might be better off starting with a wider rack and cut it to size if you can't find the ideal width.

Couldn't you just fabricate new tire rod attachment arms to keep proper geometry ?
 
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