Ke20/25 Steering Geometry - Expert Help Required

[sskoul]

Hello guys, The reason I am here is that my car is in the garage and i have stripped my steering box and drag link and the front x member is off.

 

Yes I am installing a rack and pinion. I have found an expert welder who is ready to fabricate. I know and we all know that we don't have a donor rack the size we want as the width is too small. But I am going to build a center pull rack and pinion with a wider rack like as follows.

 

 

but to do so I need some exact measurements within the next 2 to 3 days.

 

 

 

Measurements

 

A = Distance between LCA inner pivot points = 492.4mm (Credit parrot)

B = Distance between tie rod inner pivot points = 410mm (Credit parrot)

C = LCA length = 320mm (Credit parrot)

D = Perpendicular distance between LCA inner pivot center and tie rod pivot -------- ??

E = Vertical difference in height between inner LCA pivot and inner tie rod pivot = 6mm (Inner tie rod pivot is higher) (Credit Rob KE25)

 

Looking forward to input from all the experts here.

 

Thanks

 

 

Other info

 

Front Track Width (Wheel Mounting Face to Wheel Mounting Face): 1270mm (Credit styler)

Rear Track Width (Wheel Mounting Face to Wheel Mounting Face): 1295mm (Credit styler)

Edited January 24, 2015 by sskoul

[Super Jamie]

Cool idea, hope it works out for you.

 

Look up Jonny Rochester's rack and pinion conversion, he did a great writeup afterwards with all the things he did wrong.

[GJM85]

I have to adjust a tie rod tomorrow. While I'm under there I'll get some measurements for you.

[sskoul]

Cool idea, hope it works out for you.

 

Look up Jonny Rochester's rack and pinion conversion, he did a great writeup afterwards with all the things he did wrong.

 

Yeah that's quite a detailed note but it involves a lot of donor parts and not just the rack, and most of the measurements he mentioned are not of the original ke20 steering geometry. With the current idea that I have the only thing needed to be done is the rack fabrication (Not difficult at all), welding it on the x member and getting the steering linked to the rack and presto!! all geometry intact with rack and pinion accuracy! No changes what so ever to the X member mount/location, LCA inner pivots, no camber issues and using same tie rods/steering arms.

Edited December 30, 2014 by sskoul

[sskoul]

I have to adjust a tie rod tomorrow. While I'm under there I'll get some measurements for you.

 

Great! I will really appreciate that! will wait for your reply.

[oh what a nissan feeling!]

Username Rob J did a write up many years ago with all details, it was a track car and the setup was worked out very well. I will see if i can find the link when I'm on the laptop.

[parrot]

Really enjoying your thread.

 

Hopefully these may assist you in your planning, along with the measurements from others.

 

 

KE2x geometry 1.pdf

 

KE2x geometry 2.pdf

 

KE2x geometry 3.pdf

 

KE2x geometry 4.pdf

 

 

Centre tie rod pin outer to centre tie rod pin inner each side is quoted as approx 335.6mm (13.213")

 

Edit: Just remembered I had one loose in the shed. The Drag link is 410mm from centre tie rod mount to centre tie rod mount - measurement B. That's measured with a tape measure on a drag link out of a car.

Edited December 30, 2014 by parrot

[sskoul]

Really enjoying your thread.

 

Hopefully these may assist you in your planning, along with the measurements from others.

 

 

KE2x geometry 1.pdf

 

KE2x geometry 2.pdf

 

KE2x geometry 3.pdf

 

KE2x geometry 4.pdf

 

 

Centre tie rod pin outer to centre tie rod pin inner each side is quoted as approx 335.6mm (13.213")

 

Edit: Just remembered I had one loose in the shed. The Drag link is 410mm from centre tie rod mount to centre tie rod mount - measurement B. That's measured with a tape measure on a drag link out of a car.

 

EPIC Stuff. Great job dude!!

 

3 down and ONLY 2 MORE TO GO!!!

 

Come on guys!!

[sskoul]

NOTE: I am adding confirmed measurements to the 1st post.

[sskoul]

Username Rob J did a write up many years ago with all details, it was a track car and the setup was worked out very well. I will see if i can find the link when I'm on the laptop.

 

Yup have gone through that but its not the original KE20 geometry, its heavily modified. My aim is to maintain the measurements as close or even exact to the original as possible. So that's why I need confirmed measurements off of the original setup.

[sskoul]

 

D = Perpendicular distance between LCA inner pivot center and tire rod pivot -------- ??

 

110mm (If this distance is equal to eye to eye distance on the KE20 steering arm) ??

 

D = 110mm ( Is this Correct?? )

[oh what a nissan feeling!]

 

 

Yup have gone through that but its not the original KE20 geometry, its heavily modified. My aim is to maintain the measurements as close or even exact to the original as possible. So that's why I need confirmed measurements off of the original setup.

 

Really why? The original geometry is flawed rob corrected the problems with it.

[parrot]

I know nothing about the subject, but surely that's a big call? I would expect Toyota's geometry to be a manufacturers compromise, and partly a result of using a recirculating ball system for simplicity and cost. But surely it depends on the degree of modification planned for the car? Rob's car from memory was anything but standard.

[oh what a nissan feeling!]

I agree that it depends on the degree of modification planned for the car, i figured that if r&p is going in then the car is (surely?) not standard. The only reason you would bother with a rack is to improve the steering for use around corners, in which case it would pay to sort out the steering to suit non-factory ride height ect.

[ke70dave]

Depending how enthusiastic you want to get, once you get all those measurements it might be worthwhile modeling the front end in the software "optimum k" and see how it performs in bump vs camber and bump vs toe.

 

To go to this much effort I would be designing the best rather than mimicing a ~40yr old design that was designed for a steering box.