TA22 + rack and pinion

["Z" UTE]

Thanks to a suggestion and carsales link from kugzs, I have made contact with the guy selling the 3T-GTE TA22 with KE70 rack and pinion.He has kindly passed on some information. Isn't the WWW. something !!


I would have to ask his permission to reprint the details directly to this forum, But suffice to say, he used the brackets off the KE70 X member. He also used the centre shaft from the KE70 steering column (modded, ie shortened). He also said the KE70 rack was a little long for his installation, and would probably look for a shorter rack, if he was to do the job again.

However, he was mightily impressed with the precise and direct steering. Gone were the old recirculating ball instability and vagueness. He thoroughly recommended a rack and pinion conversion.

Trial and error fitment, so as not to build in bump steer. ie get your Ackerman angle correct, and all should be good.

cheers Chuck.

[75Ta22LT]

Hey Chuck,

Depending upon build costs, you might wanna advertise a group buy for this one. Especially if we can source someone who will make up a kit type unit to install into a 22.
If you plan on doing the conversion yourself, can I come help out to get an idea of whats needed?

Id definitely be interested!!!

Im sure theres a few in the CCG that would jump at the idea as well.

["Z" UTE]

75Ta22LT, mate the rack is currently sitting under the x member,connected to the struts, just figuring out the brackets at the moment. Drop round anytime mate.

If my brackets work out, I will consider making a batch.

From my understanding of many readings of the suspension bible, the angles are fairly important, but they are not that hard to set up.

cheers Chuck.

[takai]

Im considering doing it the same way that MWP has done his:

But with an AE82 rack, which should come in at the right length without shortening.

[MWP]

MWP: you used an AE92 rack with a RA28 crossmember didnt you?

AE92 rack with a TA23 xmember.
Shit, or maybe its was AE82... i cant remeber, and i didnt write it down anywhere

One tip for you Chris, mount the rack as close as possible to the xmember otherwise youll have steering geometry issues.

I did this to fix the problems i was having:

[takai]

Hehe, all good. AE92 should be slightly wider than AE82. Still wider than the 22 anyway. Itll be touch and go i reckon.

[o_man_ra23]

You need the tie rods from the centre of the ball on the rack end to the centre of the ball on the tie rod end to be identical lenght to the control arm from the centre of the ball joint to the centre of the inner bush. They also must be parallel when setup. From there, you need to have the length and placement of the rack from the ball joint on one rack rod end to the ball joint on the other rack rod end such that the vectoral positioning of the centre of the rack end ball joint to the centre of the control arm inner bush is the same as the vectoral positioning from the control arm ball joint to the tie rod end ball joint.

This might sound confusing, but its what you need to do.

Cheers, Owen

[Joshstix]

Check the AW11 and AE92 manual racks.
They are shorter than the KE70/AE86 racks and will be easier to find than Starlet racks.

Are you sure of this? I only ask because the quick rack from Quaife for both the AW11 and AE86 are the same part.

[MWP]

Are you sure of this? I only ask because the quick rack from Quaife for both the AW11 and AE86 are the same part.

Well in that case, no im not.

[RiceburnaGTV]

Good work so far guys..very interested to see the outcome.

["Z" UTE]

You need the tie rods, from the centre of the ball on the rack end to the centre of the ball on the tie rod end, to be identical lenght to the control arm from the centre of the ball joint to the centre of the inner bush. They also must be parallel when setup.
From there, you need to have the length and placement of the rack from the ball joint on one rack rod end to the ball joint on the other rack rod end, such that the vectoral positioning of the centre of the rack end ball joint to the centre of the control arm inner bush, is the same as the vectoral positioning from the control arm ball joint to the tie rod end ball joint.

This might sound confusing, but its what you need to do.

Cheers, Owen

That is one hell of a mouth full, but after reading it several times, I think I have it nutted.

So here goes my version:
Rack rod length =control arm length.
Control arm parrallel to rack rod.

Second bit:
If centre lines are drawn through all the joints, and connected to the neighbouring joints, visually you should have a parrallelogram. I tested this by grabbing 2 long welding rods, and 2 shorter rods.

Owen, have I got that correct? If not, I will edit it out.

Steering is very dynamic, with the angles between all points subject to change with road surface variations, so it is quite critical that the geometry is set correctly. By mounting a steering rack too far rearward, an increase in Ackerman angle will occur, this will change the cornering characteristics quite markedly. ie massive inside tyre scrub, and a tendancy for the vehicle to almost trip over on the inside wheel.

cheers Chuck.

[takai]

You are correct. Only substitute rack rod for tierod/tierod end. If you have a look at MWPs setup you can see how it all works. Just think that the tierod balljoint (pivot point) needs to be pretty damn close inline to the LCA inner pivot point.

[YelloRolla]

Chuck - the guy on this site has done the conversion to a KE25 suing the KP starlet rack IIRC, it is worth reading through as he goes one way and changes plan of attack.
Teh whole point of the exercise is that if it is going to fly on a KE25, the at least some of it will be relevant to the TA22.

http://1uzfe.com

Good luck.

[takai]

Are KP starlet racks easily available here in Aus though? I would have thought that they would be reasonably rare as we only got EP starlets.
Although maybe an EP starlet rack could do it well enough.

[TurboRA28]

When I was looking into them seemed best to get some send over from NZ.