A while back I was asked if a Type A power steering could use a Type B pinion and vice-verse. So I examined a Type A and Type B steering rack and pinion yesterday.

The large bearing that the pinion goes through (sits on the part of the pinion just above the helical thread) are indeed different sizes.

To convert a Type B to Type A would require either a spacer made and Toyota bearing or a completely different bearing with smaller inside diameter.

To convert Type A steering rack to Type B would require machining the rack where the large bearing sits. This would allow the use of the Type B bearing to be installed.

To be honest it would be less of a headache just to go out and purchase a second hand power steering rack of your choice.

For those who have not yet installed their upgraded pinion, I wanted to share my recent experiences with my install.

My car is a rev2 turbo, it still has no engine installed so I'm not sure if that would affect anything and is up in the air on four axle stands.

I installed my upgraded pinion in my MR2 a few days ago. It did not go according to plan. The steering pulled to the right and would try and stay there.

I did some searching on the internet and discovered a term called unbalanced steer assist.

"Unbalanced power assist. Seal leaks in the control valve or off-center steering may route hydraulic pressure into one side or the other of the boost cylinder piston causing the steering to want to turn itself to one side. if the pull suddenly vanishes an imbalance in the power steering system is to blame. "


I have a rev3 rack from Harper.

I installed his upgraded pinion with a new seal into the rack and greased all necessary parts.

To center the rack off the car, I counted the rotations and once half way was met I knew it was roughly center.

The rack was installed into my MR2 and fluid was added. The steering was turned lock to lock a few times.

Power was switched on with the steering centered and I could hear the pump activating. After a few seconds I switched off power and topped up the fluid again.

Power was switched on again and the upgraded power steering worked like it should.

I would have to say that it would seem to be a installation error or damaged seals that causes the steering to malfunction.

As I said at the start, my first try was unsuccessful.

Cool,

I will organise a trip up in the next few weeks to collect that if its ok, or if needs bed you can hold on to it, my plan is to have it fitted your car for my Xmas morning blast. Antrim coast this year weather permitting, their isnt a soap on the roads, warp speed everywhere!

Yes, please come and collect it soon. I could do with clearing bits and bobs out of my fathers garage. PM me and we will arrange a collection point and date.