rack n pinion front steer ackerman issues...explain...

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three rules in my (cough, cough) house

1) keep the wife happy
2) keep the wife happy
3) do not forget rules 1 and 2


More like in any house hahaha.....only way to keep my toys is to do the honey to do list first and foremost. Keep wife happy, then I get more toys for the car......
 
More like in any house hahaha.....only way to keep my toys is to do the honey to do list first and foremost. Keep wife happy, then I get more toys for the car......

hey....where are the pics?....your camera broke??

Have a happy Thanksgiving.
Denny
 
Looking forward to seeing your new front end, Freek. I too have drooled on the loads of inexpensive aftermarket K setups for Foxes and F bodies and wondered why nobody has done it for us. I want a rack conversion mostly for the better steering. Gearboxes are for trucks!

-Dave
 
Looking forward to seeing your new front end, Freek. I too have drooled on the loads of inexpensive aftermarket K setups for Foxes and F bodies and wondered why nobody has done it for us. I want a rack conversion mostly for the better steering. Gearboxes are for trucks!

-Dave

yea the market is much less because we are older not newer style hotrods. so it is much more difficult to design something not still readily available for everyone to buy cheaply. the stangs and maros are still being produced or have the same style over multiple years with 100s of thousands built. plus 40 yrs or more since being produced lots of rusted out junkyarded cars not around anymore. im sure by the looks of it the market for a bodies will be good.
 
you mentioned in your thread (Sept 28 / post 59) you were going to do a write up on the install of your new front suspension and add photos.....heck, maybe I missed it.

...or maybe I misunderstood.....no problem. Just running out of things to look at over the holiday.
 
you mentioned in your thread (Sept 28 / post 59) you were going to do a write up on the install of your new front suspension and add photos.....heck, maybe I missed it.

...or maybe I misunderstood.....no problem. Just running out of things to look at over the holiday.


Crap. I forgot all about posting that, I'll get it up. My bad
 
Any news?

I must say it looks a lot like another one on the market. I started working on mine again, feels good to be back in the shop and not working on new shops but that'll change after an electrical inspection
 
nah not till i get my car running. have some parts showing up now for the engine. waiting on rods and main caps. then off to the machine shop for the short block. dont have much from there to get it running. however i just demolished my daily pickup so it may put it off a bit due to replacement cost of it.
 
Sorry about the truck, I usually take 1 step forward and 2 steps back too. Such is life I guess
 
good call.....I will take you up on it.


If I can be of any assistance, let me know. I am a hot-rodder first and foremost. I got shelves full of "what ifs" when it comes to A body rack and pinion development....love innovation, just hate to see it (and $$$) wasted on stuff that already has been tried...and not worked.
 
Has anyone figured out why the front end gets pulled down when you back the car up and the wheels go into a very positive toe in.
I am ready to drive the car,just can'figure out why it's doing what it's doing, after it does that I pull forward and everything returns to normal,any ideas.
 
Has anyone figured out why the front end gets pulled down when you back the car up and the wheels go into a very positive toe in.
I am ready to drive the car,just can'figure out why it's doing what it's doing, after it does that I pull forward and everything returns to normal,any ideas.
Yes, poor geometry
 
Do you have the stock rear-steer steering arms flipped side-to-side and pointed
forward to utilize a front-steer rack and pinion?
 
Let me axe a silly question.. I have an International Scout with its stock Danna 44 front axle. The pitman arm goes forward to a drag link that pulls/pushes the spindle from in front of the axle. The left and right spindles are joined by a tie rod in front of the axle. The tie rod is shorter than the axle (in direct violation of Ackerman principles). I believe most 4X4 IH pickups of the same era had the same front suspension setup. A Scout was never meant as the best handling vehicle in the world, but wouldn't engineering an inherently 'unstable' vehicle be a corporate nightmare? Is there a reason this setup 'works' (albeit not like a Ferrarri)? This is the best picture I have of it at the moment..
Spindle.jpg
 
I think if you run a line between the upper and lower ball joints , you will find the tie rod mounting location intersects slightly behind this line to give it ackerman.
On my magnum force front they make their own steering arm to keep angle correct with a mopar spindle and Fox rack. A stock steering arm would be angled the wrong direction when flipped to the front.

IMG_1219.JPG
 
I think if you run a line between the upper and lower ball joints , you will find the tie rod mounting location intersects slightly behind this line to give it ackerman.
On my magnum force front they make their own steering arm to keep angle correct with a mopar spindle and Fox rack. A stock steering arm would be angled the wrong direction when flipped to the front.

View attachment 1714994603
Thanks. Just for giggles, I'll go check it out this evening. If memory serves (which it often does poorly), the attachment of the tie rod ends sits inboard of the ball joints on this one. Just seems a bit contrary to what I've read.
 
Thanks. Just for giggles, I'll go check it out this evening. If memory serves (which it often does poorly), the attachment of the tie rod ends sits inboard of the ball joints on this one. Just seems a bit contrary to what I've read.

It's possible on this type of vehicle you may have no ackerman angle, You could measure with turntable alignment plates .
 
My race car is a good example of the benefits(yep!) of zero ackerman as well as some problems.
I first tried to put a rack in a 65 Dart stock Kmember back in 1980. I had stock front suspension, and with a stock width rack from a pinto It turned out the inner to inner distance of the Pinto rack was WAY to wide for the early A front. I had a friend at work help narrow the rack seven inches, which is what it would take to make it work with the length of tie rod required to eliminate bump steer and still fit inside the drum brakes drums. I heated and bent the steering arms, had to notch the backing plates for the drums, got the bump steer out of it but the ackerman was zero and the turning radius was poor due to the stock arms being too long. So I cut and welded them, tested them for strength(they passed) and now I had more turning radius, but zero ackerman.
The car is a bear to push, and impossible to push in a turn without at least three or four helpers between the spool and the wrong ackerman. But for strictly drag strip use, it is tolerable and with the narrow front tires it doesn't have issues like you might think.
Now for the advantage of zero ackerman. In 1985 I got seriously out of shape at 135 mph, with the car about 30 degrees sideways or more. When I counter steered the car snapped back straight very quickly.
The reason is, in a slide at speed you WANT zero ackerman so the front end doesn't toe out when counter steering, and push the front end around , put the car into a spinout, and wreck your car in the process.
The same thing happened again at a bracket race where the car got sideways at half track ( lots more horsepower now!) to the point one guy said he could read the numbers on my side windows from the starting line. Again, it snapped right back like it was on rails when I counter steered. Third time, lost an oil filter gasket in the lights at 150 mph, same deal. Seriously sideways, got it back going straight easily, although my arse bit a chunk out of the seat!
I am slowly working on another rack conversion for a street car, and have found that a front steer rack that is narrowed five inches will work with stock steering upper and lower arms, but you will need disc brakes so the outer tie rod ends can be out where they need to be for proper ackerman. The narrow rack can be had from a drag chassis builder for about $217, I think it was Quartermax RJ race cars. If you go to the Early A section, I have a thread going about this conversion, just search my user name . The other issue I found is that with the rack narrowed five inches, it puts the steering shaft two and a half inches further in towards the center, and it has been a hassle trying to get a steering shaft snaked around the exhaust on the motor I plan on putting in my street dart. Check out the photos in that thread.
Here are a couple of photos of the race front end I built.

Dart pics + others 012.jpg


Dart pics + others 096.jpg
 
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"Thanks. Just for giggles, I'll go check it out this evening. If memory serves (which it often does poorly), the attachment of the tie rod ends sits inboard of the ball joints on this one. Just seems a bit contrary to what I've read."

Ben, If you run a string from the center of the rear axle forward through the outer tie rod end, it should also pass through the center of the lower ball joint for correct Ackerman
 
Anyone using factory spindles in a front steer application....try this test

For ackerman, turn full right OR left....doesn't matter, then look ....or measure, how much further the outer wheel is turning than the inner. That is the opposite of what it should be and it causes the outer wheel to want to roll over....not good

The reason most see the suspension pulling up and down is because of (incorrect) rack location with the factor suspension pivot points. That combination causes severe bump steer resulting in the suspension NOT being able to hold the (toe) alignment. If you take the factory suspension set up and increase the toe (in) significantly , the suspension will pull down when backing and straighten itself back out going forward. It really becomes noticeable when weight (motor /trans) is added to the car.

There are ways to make it factory spindles / LCA's work (somewhat)....but from my experience, you will spend way more than you save.
 
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