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[chrisgixer]

Bear with me on this... is there any scope in modifying the subframe to fit the rack into it in a forward location?

Hub/knuckle assembly can be reversed, ie swapped left to right easily enough. Hell, if you're already into modified sump territory, then notch the sump to accommodate the rack in a forward position...

Wouldn't be the first car to have that done, the Sierra/Granada 4x4 ran the front axle through the sump on both four pot and v6 versions

This could also give a bit more scope for the steering shaft/exhaust area, by flattening the angle of the shaft slightly

No. EVERYTHING is in the way. A front racks benefits over a rear don't justify the work involved.

Now, the question at hand...?

[chrisgixer]

That being, will the rack shaft bend?

[05omegav6]

That being, will the rack shaft bend?

Possibly a greater chance of breaking summat if you catch a curb or pothole It really depends how well made the rack is, but would it stand up to your Range Rover incident? I doubt it...

Do I need to bring Lego on Wednesday, so that you might try different approaches? Probably have enough bits to knock up an Omega chassis...

[chrisgixer]

That being, will the rack shaft bend?

Possibly a greater chance of breaking summat if you catch a curb or pothole It really depends how well made the rack is, but would it stand up to your Range Rover incident? I doubt it...

Do I need to bring Lego on Wednesday, so that you might try different approaches? Probably have enough bits to knock up an Omega chassis...

Rack body will still be above the subframe beam. But yes it might be close.

Nothing would stand up to the rr incident. Although, and here's the key, if the vertical con rod was say, a plate, or of the correct thickness to bend in an axle end on accident, but to avoid bending or flexing during cornering, then simply replacing the plate would be easy. Along with the wishbone of course

A lot depends on the number of machinings and fixings in the end of the rack shaft. Like pinning etc. May allow it to split.

Re Lego? No but there really are very few options left.

[chrisgixer]

I'm not familiar with rack innards, where are the seals, and what allows the shaft to move in the body? Bushings? Bearings?

[chrisgixer]

Power cylinder end seals might be stressed?

http://www.aa1car.com/library/steering_rack_inner_sockets.htm

[05omegav6]

Was thinking lego might be an aid to visualising what might happen under load rather than a solution

If you have a spare rack? Then pull it apart and see what's what inside

Using too thick a plate might not be a good idea, because if it doesn't flex, then all the stresses/shocks will be on the rack itself

Also, what's to prevent the rack itself from rotating horizontally in the tube as the suspension moves? You might end up destroying the rack in pretty short order, where as keeping the line of the track rod more natural from the rack to the hub should limit this effect...

I doubt you have the space for the belts and braces approach in your link. Could also fit the track rods so they drop into the hubs, using a crank on the outer end to facilitate this.

[05omegav6]

Power cylinder end seals might be stressed?

http://www.aa1car.com/library/steering_rack_inner_sockets.htm

A non power rack might reduce the effects of seal wear

[chrisgixer]

Was thinking lego might be an aid to visualising what might happen under load rather than a solution

If you have a spare rack? Then pull it apart and see what's what inside

Using too thick a plate might not be a good idea, because if it doesn't flex, then all the stresses/shocks will be on the rack itself

Also, what's to prevent the rack itself from rotating horizontally in the tube as the suspension moves? You might end up destroying the rack in pretty short order, where as keeping the line of the track rod more natural from the rack to the hub should limit this effect...

I doubt you have the space for the belts and braces approach in your link. Could also fit the track rods so they drop into the hubs, using a crank on the outer end to facilitate this.

Tre Ball joints need to line up with wishbone pivots though...  Within any slight variances manufactures have with packaging restraints, I keep reading inner ball joints must be in the correct place.

Yet, there must be lateral movement to allow the rack to move when steering, so you might expect bump steer in turns. Doesn't really happen though, so there's variance available somewhere, certainly laterally. The rack body can be slightly off centre Afaict,...


....BUT, the ball joints MUST be the same heights the wishbone pivot. Is what i'm understanding from various sources.

I'm not familiar with the correct position for and aft though.

[chrisgixer]

Power cylinder end seals might be stressed?

http://www.aa1car.com/library/steering_rack_inner_sockets.htm

A non power rack might reduce the effects of seal wear

Ok so flex in the shaft is a concern. Does the example pic make sense with the added slider ? Its purpose is to limit Torsion and flex. I'd suggest it might need to be a bigger a diameter but, I can see why it's there. Good thinking IMO.

[chrisgixer]

This pic.

[05omegav6]

It does, very much so My concern is having the space for it

[chrisgixer]

Then there's things like this. For steering box to rack conversions. I find the tre ball joint positions odd, but remove those and bin. Undo the nut on the end, add 40mm end plates or con rods, as described earlier, and bolt conventional tre's to those.

The red bit is a cradle that bolts in place of the original steering box and idler bracket holes in the body.

[05omegav6]

Now you're getting somewhere

I did wonder about obtaining a left hand drive steering idler and bracket to fit in place of the box and clamp a fitting to the tie rod. This could then receive a rose joint connected to a hydraulic ram, tother end of which could be mounted to the subframe. (Not sure of the legality of this though as I believe there must be a mechanical connection between the wheels and the steering wheel, although the Citroen CX had such a system). A remote pump could then be fitted directly to the steering column, which neatly solves the packaging issue with the steering shaft/exhaust, and does away with the power steering gubbins too...

That said a short rack could just as easily attach to the tie rod... could be a nice compact solution, whilst maintaining the Omega geometry

[chrisgixer]

Now you're getting somewhere

I did wonder about obtaining a left hand drive steering idler and bracket to fit in place of the box and clamp a fitting to the tie rod. This could then receive a rose joint connected to a hydraulic ram, tother end of which could be mounted to the subframe. (Not sure of the legality of this though as I believe there must be a mechanical connection between the wheels and the steering wheel, although the Citroen CX had such a system). A remote pump could then be fitted directly to the steering column, which neatly solves the packaging issue with the steering shaft/exhaust, and does away with the power steering gubbins too...

That said a short rack could just as easily attach to the tie rod... could be a nice compact solution, whilst maintaining the Omega geometry

Actually, thinking further, the example in that pic would be much easier to weld 40mm risers onto the black bit and or attach the ball joints wherever the hell to want. No need to touch rack ends at all.

Although the added width(of the body and black bit with ball joints) might add a few niggles, but solves more than it causes all things considered. Might be able to add the black bit to the rack I have, and weld up a cradle.