Steering rack size

[HandyAndy]

no prob.
hope my above post made some sense

Axle.... are you using extensions made from the book dimensions? if so they are too long, with the escort rack the extensions only need to be 13cm in length

cheers
andy

[HandyAndy]

oops...

just read the whole thread again...

Axle... the rack extensions supplied by MK are to the book spec which makes them too long

either shorten them to 13 cm or buy extensions from Rally design & you,ll be sorted.

the extensions shown in the book on page 76 diagram 5.36 is incorrect.
the main body of the extension needs to be 13cm .

cheers
andy

[twinturbo]

I think you will find,

The reason Chris has mentioned the shortening of the rack is so that the inner ball joint is in line with the suspension pivots. thus ensuring a constant distnace between the rack ball and the steering arm. This will negate any Bump steer. The slight difference will creatr a bit of bump but may be acceptable to the IVA.


Thats my take on it anyway.

You would not shorten the rack because your extensions were too long.

TT

[Bonzo]

Hi Axle.

If you have the book spec rack extensions you'll find that they will need shortening by approximately 15mm each ( Rack extensions ) & give or take a coulple of mm.

On my build both front wheels were still toeing out & that was after the engine, box & all the running gear fitted ( Basicaly Car on its wheels )

My extensions had been drilled quite deep & was no problem to tap a bit more thread in there

My rack is an original Ford unit ( Escort Mk2 )

If memory serves me right : The Rally Design, alloy rack extensions are OK as is.

Perhaps Ash would confirm this

The standard Escort Mk2 rack, does not need to be shortend unless you are chasing perfection ................As Chris has said in the book " It is very close to the ideal length "

[axle]

Hi Ronnie
Thanks for clearing that up.

Many thanks axle

[HandyAndy]

i think the main reason for the confusion is due to the dimensions of the rack extensions in the book are incorrect.

cheers
andy

[alga]

I think the dimensions in the book are incorrect because they assume the shortened Escort rack, with 533 mm between the ball joints. If the unmodified Escort rack is 56 cm, this would give the 3 cm extra. Sounds plausible?

[spud69]

I believe that's correct Alga, i had the same with mine and had to shorten the extensions...

[mark]

Originally Posted by alga

I think the dimensions in the book are incorrect because they assume the shortened Escort rack, with 533 mm between the ball joints. If the unmodified Escort rack is 56 cm, this would give the 3 cm extra. Sounds plausible?

This is the reason, if you are using a standard rack as most will be you need shorter extensions

I did the same thing and made book spec ones and the wheels were well out!

As HandyAndy says the ali rally design extensions are perfect and a fair bit lighter than a book spec one made from steel