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[feeutfo]

...to an omega.

Discuss.

I'm assuming more control, more direct steering input. Loosing the steering idler, and that notchy rubber square damper between column and box.

Although some steering racks can be quite notchy, pulse, and do odd things in themselves, if my mondeo was anything to go by.

The rats omega had a rack from a Nissan Almeria iirc. So, with 1000bhp on tap I'm thinking that would be good enough.


And why is it better to have a steering rack in front of the drive wheels, not behind, as it would have to be on an omega...?

[Webby the Bear]

What does the Omega have as opposed to a steering rack? I assumed ''steering idler'' was just an oof term for steering rack 

[tidla]

What does the Omega have as opposed to a steering rack? I assumed ''steering idler'' was just an oof term for steering rack 

When you have a few more pennies, get yourself this book and become top of the class.

http://www.amazon.co.uk/Light-Heavy-Vehicle-Technology-Nunney/dp/0750638273

[Entwood]

What does the Omega have as opposed to a steering rack? I assumed ''steering idler'' was just an oof term for steering rack 

Omega uses a "steering box" to give full power steering - try driving the car when being towed with the engine stationary and you'll know it !!

Steering rack is short for "rack and pinion" steering ... may I suggest a read here will explain it all much better than I can ..

http://www.carbibles.com/steering_bible.html

[Webby the Bear]

What does the Omega have as opposed to a steering rack? I assumed ''steering idler'' was just an oof term for steering rack 

When you have a few more pennies, get yourself this book and become top of the class.

http://www.amazon.co.uk/Light-Heavy-Vehicle-Technology-Nunney/dp/0750638273

I think that book (or lots similar are in the library at school  We haven't covered steering yet though sadly so was just wondering

[Webby the Bear]

What does the Omega have as opposed to a steering rack? I assumed ''steering idler'' was just an oof term for steering rack 

Omega uses a "steering box" to give full power steering - try driving the car when being towed with the engine stationary and you'll know it !!

Steering rack is short for "rack and pinion" steering ... may I suggest a read here will explain it all much better than I can ..

http://www.carbibles.com/steering_bible.html

cheers mate. ill read up 

[feeutfo]

What does the Omega have as opposed to a steering rack? I assumed ''steering idler'' was just an oof term for steering rack 

When you have a few more pennies, get yourself this book and become top of the class.

http://www.amazon.co.uk/Light-Heavy-Vehicle-Technology-Nunney/dp/0750638273

Oi steady on, its a fair question. Assuming I've read that as intended.

[05omegav6]

Rack in front of wheels would put driver input ahead of road reaction figuratively and literally. Rear mounted would add a level of damping against road inputs, and therefore improved control

Ultimately though, front or rear mounting is pure packaging compromise 

[jonny2112]

What does the Omega have as opposed to a steering rack? I assumed ''steering idler'' was just an oof term for steering rack 

The idler is actually a component part, and I only know that because my MFL failed the mot one time because of it. I ended up changing it myself (with OOF guidance of course) because my mechanic had never heard of it! I'm wondering now though if it is specific to cars with no rack, where in those days I just thought he was stupid 

[feeutfo]

Idler and steering box are simply swapped positions, to account for left and tight hand drive cars. The mounting holes are the same in the chassis rail.


Accounting for akaman(?) wheel positions so the inside wheel turns tighter, as it should, presumably means the rack must work on the exact same plain as the centre drag link on omega?


Re position front or rear, I'm having trouble seeing how the leverage from the road wheels and road imperfections feeding back to the driver through the steering, can be affected by the hub arms leading forward or trailing rearward...? Neither can have an effect on when the wheel hits a bump or road imperfection. The leverage is the same. To my mind.

[feeutfo]

Currently, I can't see it (rack position for or aft) making any odds, other than where the rack will physically fit, given current infrastructure.

[05omegav6]

http://passionford.com/forum/restorations-rebuilds-and-projects/231097-zzz-zzz-sleeper-granada.html

To save rummaging tail end of reply #7

Subframe mounts at front of the chassis rail and aboot halfway down the inner wing. Double wishbone fully independent set up.

Rear suspension basically the same as the Omega with out the tie rods, so arguably a poorer design

[Nick W]

Steering racks and boxes are both gear systems. Properly setup, there is no theoretical advantage to either. Replacing a properly engineered box with a properly engineered rack isn't going to make any appreciable difference to the driver.
Racks tend to be more compact, but packaging a rigid 1.5m rod across the front of the car can be quite challenging, especially in a RWD car. This is why you see both front and rear mounted racks. RWD Escorts have it in front of the cross member, Avengers at the back. Both are similar sizes, with strut front ends.
The extra linkages that a box requires can make the packaging easier; the Pitman arm(and attendant idler arm on the otherside) can be used to space the centre tie rod up or down as necessary. A Superminx for example has the centre rod running along the bulkhead above the bell housing.
In use, you tend to find that boxes are more robust/durable, but the linkages wear; whereas wornout racks aren't particularly unusual.
Replacing a box with a rack is probably best considered an interesting engineering exercise rather than a practical thing to do.

[feeutfo]

There are sound space saving reasons, for this thread.

[05omegav6]

Been digging through my Haynes collection

Mk2 Granada front suspension, whilst an antiquated design, is completely self contained, so could in theory at least, be bolted onto any chassis of a suitable width. Two horizontal bolts each side through the chassis rails approx 18" apart.

Mk3 Granada, and Sierra front suspension is McPherson based. Accurate location for geometric precision essential and difficult. Both cars have the same subframe with longer arms on the Granada. Two vertical bolts either side into the chassis rails approx 5" apart.

All three cars have the rack mounted ahead of the wheel centre line, and use an intermediate shaft to connect to the column. All three available with or without power steering. The later design runs the ARB back to the chassis rails, where they drop beneath the floorpan. The earlier design keeps everything forward of the wheel line allowing a shed load of space for V8 stylee exhaust systems, the only considerations being the actual chassis width, front hub/brake details, adjusting the intermediate steering shaft to suit and finally suitably rated springs.