Quick rack

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Quick rack

Postby chrismc » Thu Jun 05, 2014 8:36 pm

I decided to have a go at building a quick rack kit from TJ Motorsport. This changes the steering ratio and instead of 3.5 turns lock to lock it will be 2.5. This is at the expense of very heavy steering at lower speeds.

The kit consists of just the Rack and the Pinion and is beautifully machined.

Here it is below the rack

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The first thing to do is it cut through or drill out the staking which attach the control arms to the rack.

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Once this is done the joint can be removed.

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The plate can be removed from the spring loaded thrust piston thing :lol: and this can be withdrawn.

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The rack is then wound until it reaches the end of its travel There is a gap in the rack teeth which allows the pinion to be tapped out after removing the bottom plate.

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One of my bearings was shot and I couldn't locate another so I made a plain bearing out of leaded bronze.

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Hopefully this will do the job.

The bush staked in place.

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The thrust piston then had to be shimmed ensuring the rack didn't lock up when it was fully tightened.

Here is a comparison of the new and original pinions

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And a pic of the rebuilt rack with the old parts below.

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Just need to build up my biceps now. :lol:
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Re: Quick rack

Postby droopsnoot » Fri Jun 06, 2014 10:18 am

Thanks for the write-up. I've considered doing one of these but my MOT man complains about how heavy the standard steering is and keeps suggesting power steering. I had a similar thing (but from many years ago) on my old Sportshatch, and with that small steering wheel and 205 tyres on it, it could be quite unpleasant at parking speeds. Especially when I forget to check the tyre pressures...

Are there any numbers on that old pinion bearing that you could let me have? I'd like to add them to my list of things to keep a lookout for at autojumbles.
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Re: Quick rack

Postby chrismc » Fri Jun 06, 2014 11:09 am

Yeah the steering will be heavy at low speeds. I used to have one on my old escort 10 years ago. Great fun but hoping the old muscles are still up to it.

The number on the bearing is documented here:

viewtopic.php?f=14&t=23243

Thanks Chris
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Re: Quick rack

Postby droopsnoot » Fri Jun 06, 2014 12:53 pm

So it is! I remember asking now, then completely forgetting to go back and have a look for a reply.

Cheers
Mike.
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Re: Quick rack

Postby hbpeter » Sat Jun 07, 2014 7:47 pm

How will the bush you made be lubricated? Wouldnt want it to seize up mid corner!!

Peter
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Re: Quick rack

Postby chrismc » Sat Jun 07, 2014 9:14 pm

Hi Peter,

The Bush will periodically be lubricated with oil. It can be accessed by levering off the plastic dust cap.

The material I used is Leaded Bronze SAE 660 which has excellent low friction and anti seize properties.

Thanks Chris
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Re: Quick rack

Postby hbpeter » Sat Jun 07, 2014 9:35 pm

Fair enough, wouldnt some sort of grease be better.

Peter
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Re: Quick rack

Postby chrismc » Sun Jun 08, 2014 10:26 am

What sort of grease would you recommend for this application Peter? :)
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Re: Quick rack

Postby hbpeter » Sun Jun 08, 2014 9:18 pm

I was thinking of some sort of graphite based grease, that would impregnate the bush and provide lubrication, or something like wheel bearing grease, more for the high pressure than temp. But no expert.

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Re: Quick rack

Postby chrismc » Mon Jun 09, 2014 2:52 pm

Hi Peter,

After doing a bit of reading up I have decided to use EP90 gear oil. This will run into the bearing and keep it lubricated.

Thanks Chris

:thanx:
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