Rack and pinion steering.

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The way I see it, is if the lower ball joint arms cam be duplicated in height from the ground then that's a good starting point. If the rack is in the same place as original steering linkage then it can't over center.
Sean, I like your ideas. You've built your car completely, chassis and everything, just as I am.
Kiss, yes I agree.
 
Others have brought up a lot of good points already, but I'll also jump in and say it takes a considerable amount of work to convert to a front steer set-up in a mopar. It takes even more work to make a R&P work with reasonable geometry after that.

If you were going to try this, I'd avoid using the stock lower control arm and ball joint/ steering arm altogether. Use an oval track lower control arm that utilizes the mopar upper ball joint to mount the spindle and utilize a fabricated steering arm, and a rear facing strut arm to allow the rack ends room to move with suspension articulation. Then get the widest rack you can and mess with all the bump measurement adjustments to get the rack end arcs to better align with the control arm arc.

This is a basic illustration of rear steer mopar ackerman. With a front steer set-up, those steering arms would need to be further outboard to maintain the angles...and this is only one of numerous angles you would need to check, modify and adjust.
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I would say it's a 100% a race only modification. Use a developed kit like Hemi Dennys stuff. Would not recommend it I went through hell making sure my geometry was right. If it wasn't for the guidance from the guys who did this in the day in pro stock. I wouldn't have done it period even with my prior experience having done chassis work professionally it was a lot to maintain acceptable angles. "key word acceptable not ideal" My car has 2 1/4 in headers on a pro stock hemi so that is a huge factor. (plus trying to go period correctish)

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I would say it's a 100% a race only modification. Use a developed kit like Hemi Dennys stuff. Would not recommend it I went through hell making sure my geometry was right. If it wasn't for the guidance from the guys who did this in the day in pro stock. I wouldn't have done it period even with my prior experience having done chassis work professionally it was a lot to maintain acceptable angles. "key word acceptable not ideal" My car has 2 1/4 in headers on a pro stock hemi so that is a huge factor. (plus trying to go period correctish)

View attachment 1716347049

View attachment 1716347050

View attachment 1716347051
Thank you
 
Others have brought up a lot of good points already, but I'll also jump in and say it takes a considerable amount of work to convert to a front steer set-up in a mopar. It takes even more work to make a R&P work with reasonable geometry after that.

If you were going to try this, I'd avoid using the stock lower control arm and ball joint/ steering arm altogether. Use an oval track lower control arm that utilizes the mopar upper ball joint to mount the spindle and utilize a fabricated steering arm, and a rear facing strut arm to allow the rack ends room to move with suspension articulation. Then get the widest rack you can and mess with all the bump measurement adjustments to get the rack end arcs to better align with the control arm arc.

This is a basic illustration of rear steer mopar ackerman. With a front steer set-up, those steering arms would need to be further outboard to maintain the angles...and this is only one of numerous angles you would need to check, modify and adjust.
View attachment 1716347034
Thank you
 
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!
Has anybody tried using/adapting 1st-Gen 2WD Dakota frt end stuff? I have thought about it, & am getting ready to bust 2 of them down into parts, one of them My now retired/frame-rotted Trusty Rusty. It seemed to handle well, & I did nothing to the Caster/Camber, I'm sure it could've been dialed in to carve well.....
20210925_164740.jpg
 
Has anybody tried using/adapting 1st-Gen 2WD Dakota frt end stuff? I have thought about it, & am getting ready to bust 2 of them down into parts, one of them My now retired/frame-rotted Trusty Rusty. It seemed to handle well, & I did nothing to the Caster/Camber, I'm sure it could've been dialed in to carve well.....View attachment 1716347124
Sean mentioned the Dakota rack.
 
Yes, but it's the steering-arms/knuckles, & the relative positions that make or break the usefulness of any forward-mount R&P.
Okay thanks, at this point I'm just trying to learn & figure stuff out. I am a know not right now.
 
see if I should or shouldn't work on someone else's car
I apologize. What I said was harsh. But, please don't throw the baby out with the bath water. Take my one critical sentence out of what I posted and I would hope you would see the value in my suggestions.

You don't need it, it will be worse than factory. There are so many compromises and absolutely no advantage to doing it with OEM stuff. Structurally and geometrically it is at a disadvantage.

If you truly need it (1.75" header primaries, weight reduction, sealed hub spindles, .....) then do Alter-k-tion or Hemi Denny. With a well designed and PROVEN system you can utilize much better rear sump pans, miles to spare for header clearance, can do Corvette sealed sealed hubs. IFS used to be favored for disc brakes but you can get a brake setup to fill any need from drag race to road race in on a Mopar spindle so that's a mute point.

I apologize @MOPARMAGA
 
I apologize. What I said was harsh. But, please don't throw the baby out with the bath water. Take my one critical sentence out of what I posted and I would hope you would see the value in my suggestions.

You don't need it, it will be worse than factory. There are so many compromises and absolutely no advantage to doing it with OEM stuff. Structurally and geometrically it is at a disadvantage.

If you truly need it (1.75" header primaries, weight reduction, sealed hub spindles, .....) then do Alter-k-tion or Hemi Denny. With a well designed and PROVEN system you can utilize much better rear sump pans, miles to spare for header clearance, can do Corvette sealed sealed hubs. IFS used to be favored for disc brakes but you can get a brake setup to fill any need from drag race to road race in on a Mopar spindle so that's a mute point.

I apologize @MOPARMAGA
I appreciate your response, you're right I will make the best of what I have for now until I can afford to buy something ( which I don't like doing) but something like a hdk would be way better than what I want to do.
I have 2.125 primary tti with no clearance issues and I think for now buying a 20.1 manual box will be my best option.
 
20.1 manual box will be my best option
That would be a good choice. The OEM stuff works to a great extent and it gets to a point where something(s) dictates spending a bunch on non-OEM stuff.

Look into the electronic power steering swap threads. Added to a 20:1 manual you get rid of a belt just like r&p to reduce parasitic loss. Crisp steering with the ratio and power with electric. If your headers fit with a manual box then go for it.
 
That would be a good choice. The OEM stuff works to a great extent and it gets to a point where something(s) dictates spending a bunch on non-OEM stuff.

Look into the electronic power steering swap threads. Added to a 20:1 manual you get rid of a belt just like r&p to reduce parasitic loss. Crisp steering with the ratio and power with electric. If your headers fit then go for it.
Thanks, I will check into that.
This being a dedicated drag car, I'll be looking to do the lighter weight option.
 
I personally love the center link through the oil pan, because every time a Chevy guy sees it, it blows their mind. Besides, how much will you be pulling the motor? It's not like it takes an act of congress to get the center link off.
 
I personally love the center link through the oil pan, because every time a Chevy guy sees it, it blows their mind. Besides, how much will you be pulling the motor? It's not like it takes an act of congress to get the center link off.
Hopefully just pull the engine once, after this coming season to see if anything is weird, if there's no weird...it will stay in for a couple seasons.
One of the other reasons I was thinking of moving the steering is I need a diaper to run the e t I think the car will run & that link might add to the cost of a custom diaper.
 
This has me curious. I’ve never mapped out factory a-body suspension in a software, but for those that have, what is the ideal location and length for a front steer rack/steering arms, and still get good geometry for Ackerman, bump, and toe? I used suspension analyzer when designing the front end on my ‘69 and it took days to get that dialed in, and I still paid an expert to fine-tune it. That said, with available suspension software, the ability to get different length racks, and produce a steering arms, what does it take? I’m kind of surprised it hasn’t been done yet, and maybe it’s been studied and tested and that’s why we have coil over kits with M2 knuckles. Would love to hear from those that have actually run this through software, or mapped it out.
 
I've got a suspension analyzer but I've never used it to design new pick up points for a rack conversion. It isn't really designed to do that but you could plot them out and see what happens to everything as a result, which could give you the direction of where to move things to keep geometry reasonable. You then have to be able to transfer those measurements into the steel of the car front stub. Its not impossible, its just a lot of work for little reward. It would also require parts that are not available on the open market, which is why there is no kit to do this and all of the coil over conversion kits start from scratch with GM or Ford spindles and related parts.

Doing this while retaining the stock spindle would require custom steering arm to retain ackerman. This arm could be made to accommodate the upper mopar ball joint since it would be imposible to build one with an integrated ball joint like the stock unit. There isn't an aftermarket lower control arm made specifically for mopars to utilize the upper ball joint in the lower position, but 73-80 B body arms might be able to be made to work. There are some circle track arms that use the mopar upper ball joint in both upper and lower positions that might be able to be used. But back to the steering arm, it would be required it to be outboard of the brake rotor which could result in rim interference depending on length of the arm you want for steering ratio and depth of the wheel being used.

Relative to the B body arm mentioned above, this may require new, shorter upper arm to maintain caster/camber relationships. If you have never measured them, A body lower control arms are actually longer than B body units. While there is not a selection of various length upper arms on the market, use of SPC units might allow this to work since they are a turnbuckle design.

Once you have a rack in front of the spindle, you may then run into strut rod interference depending on location of the rack. You could position the rack up or down to reduce this, but that could impact travel one way or the other and may require differing length rack ends to avoid the interference. Changing the length of the ends will have an impact on bump steer through suspension movement which could get really squirrely. Of course, the solution here is to alter the strut rod. If you shorten it, you now are introducing more extreme angle changes through range of motion. You could lengthen it to avoid that but may not have a structural point available to mount it ahead of where it currently resides. Ma already made these pretty long to reduce dynamic changes through the arc of movement. You may be able to mount it on the trailing side but this will require swapper the lower control arm side to side, if using a stock arm, to maintain the strut angle. Even if you use a fabricated arm to customize the strut location on the arm, you still need to find a rear anchor point that will minimize changes in one direction of the other. This may require it to go right into the frame rail which is more cutting and fabrication.

Of course to avoid the strut issue, you could convert the lower control arm to an A arm style like Reilly or XV. This avoids the strut issue, but you now need to create mounts for the A locations that will allow it to move up and down in parallel to the upper arm without introducing angular changes through the range of motion. This is a challenge because of the forward bias of the K frame does not provide a rear mounting location for the A arm which could result in a very long and over-leveraged mount if you try to hang it off the K frame., which you have to do because there is nothing physically in that location if you remove the pitman and idler.

So after looking at all of these changes and how some of them can be almost irreversible should you ever want to go back to stock, you can see why the aftermarket has simply created a clean sheet design for good geometry R&P utilization. Doing this also allows you to clean up some of the OEM shortcoming of the mopar design. While it was great against its contemporaries, it can be improved upon with what is available these days.
 
Motown Missle already done what your wanting to do. Contact

Mark Williamson on facebook he owns the drag car today.​

 
I've got a suspension analyzer but I've never used it to design new pick up points for a rack conversion. It isn't really designed to do that but you could plot them out and see what happens to everything as a result, which could give you the direction of where to move things to keep geometry reasonable. You then have to be able to transfer those measurements into the steel of the car front stub. Its not impossible, its just a lot of work for little reward. It would also require parts that are not available on the open market, which is why there is no kit to do this and all of the coil over conversion kits start from scratch with GM or Ford spindles and related parts.

Doing this while retaining the stock spindle would require custom steering arm to retain ackerman. This arm could be made to accommodate the upper mopar ball joint since it would be imposible to build one with an integrated ball joint like the stock unit. There isn't an aftermarket lower control arm made specifically for mopars to utilize the upper ball joint in the lower position, but 73-80 B body arms might be able to be made to work. There are some circle track arms that use the mopar upper ball joint in both upper and lower positions that might be able to be used. But back to the steering arm, it would be required it to be outboard of the brake rotor which could result in rim interference depending on length of the arm you want for steering ratio and depth of the wheel being used.

Relative to the B body arm mentioned above, this may require new, shorter upper arm to maintain caster/camber relationships. If you have never measured them, A body lower control arms are actually longer than B body units. While there is not a selection of various length upper arms on the market, use of SPC units might allow this to work since they are a turnbuckle design.

Once you have a rack in front of the spindle, you may then run into strut rod interference depending on location of the rack. You could position the rack up or down to reduce this, but that could impact travel one way or the other and may require differing length rack ends to avoid the interference. Changing the length of the ends will have an impact on bump steer through suspension movement which could get really squirrely. Of course, the solution here is to alter the strut rod. If you shorten it, you now are introducing more extreme angle changes through range of motion. You could lengthen it to avoid that but may not have a structural point available to mount it ahead of where it currently resides. Ma already made these pretty long to reduce dynamic changes through the arc of movement. You may be able to mount it on the trailing side but this will require swapper the lower control arm side to side, if using a stock arm, to maintain the strut angle. Even if you use a fabricated arm to customize the strut location on the arm, you still need to find a rear anchor point that will minimize changes in one direction of the other. This may require it to go right into the frame rail which is more cutting and fabrication.

Of course to avoid the strut issue, you could convert the lower control arm to an A arm style like Reilly or XV. This avoids the strut issue, but you now need to create mounts for the A locations that will allow it to move up and down in parallel to the upper arm without introducing angular changes through the range of motion. This is a challenge because of the forward bias of the K frame does not provide a rear mounting location for the A arm which could result in a very long and over-leveraged mount if you try to hang it off the K frame., which you have to do because there is nothing physically in that location if you remove the pitman and idler.

So after looking at all of these changes and how some of them can be almost irreversible should you ever want to go back to stock, you can see why the aftermarket has simply created a clean sheet design for good geometry R&P utilization. Doing this also allows you to clean up some of the OEM shortcoming of the mopar design. While it was great against its contemporaries, it can be improved upon with what is available these days.
Many great points and ideas & I will gladly say at this point, i am not smart enough to try any of it.
 
Many great points and ideas & I will gladly say at this point, i am not smart enough to try any of it.

It's not hard to do it right. I did it because I moved the engine back 8 or 9 inches. There was no way to keep the OE **** and make it all fit, so I converted it to front steer R&P.

Again, it's not hard. It's just unnecessary work if you can get headers that fit. And the sad fact is that move to R&P unceremoniously screwed me. HARD.

I decided I could get rid of the pan with the center link through it because I didn't have the center link any more. That was a HUGE jack off on my part. That allowed me to try TWO different box style pans. Neither was worth a stinking ****. The Milodon was far better at oil control than the Stef's but both were a power loser to the Super Stock pan. That Stef's pan was straight garbage, but because it had a 1.5 inch kick out (IIRC) at 8500 and up it was 10-12 better. Maybe it was a bit better at 8k too but neither was enough to warrant all the parts that **** box pan broke.

Now you know why I try and get Milodon to start making that pan and pick up again, but they always talk me back off the ledge and remind me that no one would buy them because they smash them into **** all the time. I have never bashed mine in, or the Moroso pans I've used.

It's not can it be done or will it be safe. It can be done and it is safe. The issue is it worth the work. The answer is a resounding NO if you can get headers that fit. Or if you think you need more weight on the rear axle and you want to move the engine back. That too is not necessary any more.
 
It's not hard to do it right. I did it because I moved the engine back 8 or 9 inches. There was no way to keep the OE **** and make it all fit, so I converted it to front steer R&P.

Again, it's not hard. It's just unnecessary work if you can get headers that fit. And the sad fact is that move to R&P unceremoniously screwed me. HARD.

I decided I could get rid of the pan with the center link through it because I didn't have the center link any more. That was a HUGE jack off on my part. That allowed me to try TWO different box style pans. Neither was worth a stinking ****. The Milodon was far better at oil control than the Stef's but both were a power loser to the Super Stock pan. That Stef's pan was straight garbage, but because it had a 1.5 inch kick out (IIRC) at 8500 and up it was 10-12 better. Maybe it was a bit better at 8k too but neither was enough to warrant all the parts that **** box pan broke.

Now you know why I try and get Milodon to start making that pan and pick up again, but they always talk me back off the ledge and remind me that no one would buy them because they smash them into **** all the time. I have never bashed mine in, or the Moroso pans I've used.

It's not can it be done or will it be safe. It can be done and it is safe. The issue is it worth the work. The answer is a resounding NO if you can get headers that fit. Or if you think you need more weight on the rear axle and you want to move the engine back. That too is not necessary any more.
Okay, I trust you're opinion.
I have really no need to want to do this, only for a universal diaper lol.
I might need to get checked into an institution if Im willing to try all that instead of getting a custom diaper lol .
 
Okay, I trust you're opinion.
I have really no need to want to do this, only for a universal diaper lol.
I might need to get checked into an institution if Im willing to try all that instead of getting a custom diaper lol .


The custom diaper is far cheaper and way way less work
 
I've got a suspension analyzer but I've never used it to design new pick up points for a rack conversion. It isn't really designed to do that but you could plot them out and see what happens to everything as a result, which could give you the direction of where to move things to keep geometry reasonable. You then have to be able to transfer those measurements into the steel of the car front stub. Its not impossible, its just a lot of work for little reward. It would also require parts that are not available on the open market, which is why there is no kit to do this and all of the coil over conversion kits start from scratch with GM or Ford spindles and related parts.

Doing this while retaining the stock spindle would require custom steering arm to retain ackerman. This arm could be made to accommodate the upper mopar ball joint since it would be imposible to build one with an integrated ball joint like the stock unit. There isn't an aftermarket lower control arm made specifically for mopars to utilize the upper ball joint in the lower position, but 73-80 B body arms might be able to be made to work. There are some circle track arms that use the mopar upper ball joint in both upper and lower positions that might be able to be used. But back to the steering arm, it would be required it to be outboard of the brake rotor which could result in rim interference depending on length of the arm you want for steering ratio and depth of the wheel being used.

Relative to the B body arm mentioned above, this may require new, shorter upper arm to maintain caster/camber relationships. If you have never measured them, A body lower control arms are actually longer than B body units. While there is not a selection of various length upper arms on the market, use of SPC units might allow this to work since they are a turnbuckle design.

Once you have a rack in front of the spindle, you may then run into strut rod interference depending on location of the rack. You could position the rack up or down to reduce this, but that could impact travel one way or the other and may require differing length rack ends to avoid the interference. Changing the length of the ends will have an impact on bump steer through suspension movement which could get really squirrely. Of course, the solution here is to alter the strut rod. If you shorten it, you now are introducing more extreme angle changes through range of motion. You could lengthen it to avoid that but may not have a structural point available to mount it ahead of where it currently resides. Ma already made these pretty long to reduce dynamic changes through the arc of movement. You may be able to mount it on the trailing side but this will require swapper the lower control arm side to side, if using a stock arm, to maintain the strut angle. Even if you use a fabricated arm to customize the strut location on the arm, you still need to find a rear anchor point that will minimize changes in one direction of the other. This may require it to go right into the frame rail which is more cutting and fabrication.

Of course to avoid the strut issue, you could convert the lower control arm to an A arm style like Reilly or XV. This avoids the strut issue, but you now need to create mounts for the A locations that will allow it to move up and down in parallel to the upper arm without introducing angular changes through the range of motion. This is a challenge because of the forward bias of the K frame does not provide a rear mounting location for the A arm which could result in a very long and over-leveraged mount if you try to hang it off the K frame., which you have to do because there is nothing physically in that location if you remove the pitman and idler.

So after looking at all of these changes and how some of them can be almost irreversible should you ever want to go back to stock, you can see why the aftermarket has simply created a clean sheet design for good geometry R&P utilization. Doing this also allows you to clean up some of the OEM shortcoming of the mopar design. While it was great against its contemporaries, it can be improved upon with what is available these days.
You’re right, there is a lot to it but anytime I’ve heard anything about why it can’t/shouldn’t be done, I read a lot of assumptions; a lot of might/probably/may/possibly. All of it might be true, but I’ve never read anything about the factory suspension being plotted to understand exactly what’s needed to get it done. Again, could be too much hassle so the conversion is simpler. I used a completely different knuckle on my ‘69 so had to start from scratch. If I still had suspension analyzer I’d plot it myself to see what the issues really are. To me it’d be interesting to truly understand what it would take and what the interferences actually are and if they could simply be overcome.
 
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