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squbti
24th August 2009, 07:48 PM
hi all, i have a mk1 steering rack & will be making the extensions tomorrow & was wondiring if the drawing 5.36 on page 76 is the right length for a non modified mk1 or mk2 or is it for the ideal length of 533? does anyone know the total length of the steering rack (cc balljoints)?
cheers
Samy

londonsean69
24th August 2009, 11:06 PM
Can't help with the total length as mine isn't installed. But are you aware that the MK1 Escort has a different (imperial) thread. Apparently.

Sean

mark
25th August 2009, 09:11 AM
I believe as londonsean says that the mk1 rack has an imperial thread so would need different extensions (internal thread imperial/external metric to suit tre)

Most people buy new mk2 racks from rally design.

The book extensions are for a modified rack so are too long, but the alloy extensions from rally design are perfect for the job, as are the alloy rack clamps they sell (im not on commision honest!:D)

hopoe this helps

ps. do you want rally designs phone no. ;)

squbti
26th August 2009, 08:15 PM
hey guys , thanks for the info. i am aware about the threads & so on & so on......:D what i realy want to know is how long should the extensios be for a non modified MK1 or 2 rack?
thanks
Samy

squbti
26th August 2009, 09:08 PM
i cant find in the book where it says whether the extensios in the drawings are for the modified or non modified rack ! did i miss something ? can you buy modified racks off the shelf? :confused: as far as i know the mk1 & mk2 everyone buys are the same length . so how long ahould the extension be?
Cheers

mark
26th August 2009, 10:48 PM
i cant find in the book where it says whether the extensios in the drawings are for the modified or non modified rack ! did i miss something ? can you buy modified racks off the shelf? :confused: as far as i know the mk1 & mk2 everyone buys are the same length . so how long ahould the extension be?
Cheers


I couldnt find a modified rack off the shelf so have a new mk2 escort rack.

My original extensions were to book spec and were definately too long.

i havnt got the length of the ones that i used to hand at the moment but if someone doesnt come along with a dimension for you in the mean time, i will measure mine for you tommorow.

I think they need to be approx 30mm shorter each side if i remember correctly but will confirm tommorow.

Hope this helps

mark
26th August 2009, 10:52 PM
If you go onto rally designs website and type in the search box the code DAR024 thats what i used and they are perfect :)

They say that they extend by 120 to 130mm per side

HandyAndy
26th August 2009, 10:57 PM
If you go onto rally designs website and type in the search box the code DAR024 thats what i used and they are perfect :)

They say that they extend by 120 to 130mm per side

nice & light weight too , eh Mark ??;) :D

andy:)

mark
27th August 2009, 05:08 PM
My extensions are 130mm long with a 25mm long external thread and 67mm deep internal thread.

Hope this helps

squbti
27th August 2009, 05:19 PM
thank you so so much Mark , that was a great help . i thought they kinda looked too long when i was making them but i can easily shorten them to 130.
thanks for the help
Samy

georgenewman1
28th August 2009, 12:14 AM
hi guys, i shortened my rack myself from the sierra donor, its simple enough all you need is a 14x1.25 tap to tap the end or the shortened rack and you can make it any length you want, is there some reason for not doing thes that i have missed

londonsean69
28th August 2009, 12:51 AM
its simple enough all you need is a 14x1.25 tap to tap the end or the shortened rack

What did you tap??

Do you mean you threaded the existing ends of the sierra steering rack? (I assume after cutting them down)

Any particular reason you used M14x1.25? Is that the thread on the existing rack ends (steering ball joints?).

If this works (no reason it wouldn't) it would make the build a lot easier. But doesn't the Sierra have power steering - I don't know, never driven one and I have an Escort rack.

Sorry for so many questions, just interested in how everyone accomplishes stuff:D

Sean

Bonzo
28th August 2009, 09:41 AM
As a rule the Sierra was fitted with a manual steering rack. The threads on the track rods is M14 X 2

The XR & 2 Litre DOC Sierra came with power steering & I believe it was an option on other models.

Chris has stated that the Sierra rack is not suitable to use without modification.
It is not a simple matter of altering the length of track controll arms. The problem lies in the rack & pinnion section of the rack, it is too long & needs to be shortened by having it machined.

I had rack extensions made to the book speck & found that they needed to be shortened by 30mm each.
Lucky for me that they had a deep enough bore for me to tap a deeper thread ( M14X2 )

RAYLEE29
28th August 2009, 03:00 PM
Hi, George sorry to be the bearer of bad news but what you describe above is totally wrong and will not result in a safe and proper modification and also the handling of the car will be adversely affected.
Why I hear you say
1 the threads on the track rods on the sierra rack are 14x2
2 you cannot simply cut down the rods and rethread they are rolled threads,
rolling a thread increases the od of the thread cutting with a die does not
3 the rack length is totaly wrong it needs the inner ball joints to line up with a theoretical line drawn between the wishbone pivots when the steering is in a dead ahead position (there is a pic of this in the book)
if you dont have the correct rack length you car will suffer from acute bump steer and be very dangerous
I hope you understand what ive written and take it onboard for your own safety
Ray

squbti
28th August 2009, 04:25 PM
hi guys , i think the sierra rack is very simmular to the mk2 in its simplicity but is a litle longer & to make iether one shorter is preaty much the same & has nothing to do with the outer rods but it is the inner rod that has to be shortend & rethreaded & now the housing would become too long & also has to be shortend , too much work if you ask me :D alread have my hans full so i got an mk1 from a friend works just fine & the emperial threads are no big deal. however i will be saving my sierra rack & maybe do that project some other time.
Cheers
Samy