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Steering improvements
panichat - 25/3/11 at 07:31 PM

My car has been on the road for 7 months. I love it. I use it every day in all weather (ok - not snow). Driving it puts a big smile on my face.
But there is one thing that still bugs me and that I haven't really been able to solve to my satisfaction - the steering is heavy and it has "IVA pass but unsatisfactory" self centring. This seems to be such a common complaint on here - it affects book built cars, kits of all sorts, cars with cortina uprights (like mine), cars with sierra uprights ... etc!
I know there have been issues with the various books and with some of the manufactured components, and a lot of people have opinions, but is anyone able to give a definitive set of dimensions/data points that would give excellent steering. I would happily remove suspension brackets and start from scratch if I could be sure of making a big improvement.

Cheers
Dave


myke pocock - 25/3/11 at 07:37 PM

For what its worth, Ile second that one Dave. Mines purely book measurements. (1st Edition, dont know if the dimensions changed in the 2nd Edition)


Mark Allanson - 25/3/11 at 07:57 PM

Mine is a book chassis with cortina uprights, I redesigned the upper wishbones and have perfect self centring


rusty nuts - 25/3/11 at 08:08 PM

Do you have a Sierra column using the plastic bush where it goes through the bulkhead? One of the best mods I've done to my car was to change it for a self aligning bearing for about a tenner. Self centering was vastly improved without the need for and major work . Have found some Allegro ball joints to bit a bit tight as well


big_wasa - 25/3/11 at 08:28 PM

Ive done both of the above. If they are book bones there was a cock up and they halfed the 7 or so deg' of castor they should have.


steve m - 25/3/11 at 08:37 PM

Mine is also book one edition built, and my steering was heavy, but i put that down to the 205/55 tyres more than a steering/chassis design error,
however i now have a quick rack in the car, and from my brief test sessions last week, feel that the steering is lighter

Steve


40inches - 25/3/11 at 09:23 PM

quote:
Originally posted by steve m
Mine is also book one edition built, and my steering was heavy, but i put that down to the 205/55 tyres more than a steering/chassis design error,
however i now have a quick rack in the car, and from my brief test sessions last week, feel that the steering is lighter

Steve

If the steering is lighter with a quick rack, the original rack was fubar, quick racks usually mean heavier steering.


Daddylonglegs - 25/3/11 at 09:42 PM

Built mine to the McSorley plans but made the caster around 7deg by modifying the wishbone build. I hope it won't be too long before I find out if it self centres


Macbeast - 25/3/11 at 10:19 PM

Rusty - do you have part number / supplier for the bearing ?


panichat - 25/3/11 at 10:31 PM

Mark (Allason)
Can you give the details of your redesign for the wishbones?

I did the bearing mod to replace the sierra column bearing, but didn't make a lot of difference.

I guess the perfect outcome would be a diagram that gives the relative position of the upper bj and the lower bj for perfect steering.
Thanks
Dave


myke pocock - 25/3/11 at 10:52 PM

So, is it a case of cutting the top wishbone mounts off the chassis and re-welding them in the correct position? If so, as has been asked is there a drawing of the correct position?


panichat - 26/3/11 at 09:16 AM

Thanks for the replies ...
it seems we hanen't really got a solution to this.
Perhaps if I draw a diagram for people to contribute dimensions to we may get closer.

Cheers
Dave


rusty nuts - 26/3/11 at 09:46 AM

quote:
Originally posted by Macbeast
Rusty - do you have part number / supplier for the bearing ?


Sorry mate , lost the details when the PC went tit's up . IIRC I saw the mod on the Robin Hood owners site and it was then posted on here by Mr Henderson? Worth doing a search . Unless the original Sierra bush is exactly set up at right angles to the column it will cause binding , any friction on the column makes the steering stiffer reducing self centering. Might also be worth jacking the car up , disconnecting the track rod end and turning the hub lock to lock to check for any tight ball joints


40inches - 26/3/11 at 09:57 AM

The rule of thumb, with MK anyway, is to move the top wishbones 20mm back.
On my MK the top wish bone mounts are asymmetrical, the offside ones are 15mm further back than the nearside, plus the wishbones are 10mm different one side to the other
Instead of completely replacing the top wishbone mounts, you could cut off the rear mounting bracket leg and make new L shaped brackets to weld on, this would give a large range of adjustment using the standard wishbones, use spacers to fill in the gaps.


40inches - 26/3/11 at 10:05 AM

quote:
Originally posted by rusty nuts
quote:
Originally posted by Macbeast
Rusty - do you have part number / supplier for the bearing ?


Sorry mate , lost the details when the PC went tit's up . IIRC I saw the mod on the Robin Hood owners site and it was then posted on here by Mr Henderson? Worth doing a search . Unless the original Sierra bush is exactly set up at right angles to the column it will cause binding , any friction on the column makes the steering stiffer reducing self centering. Might also be worth jacking the car up , disconnecting the track rod end and turning the hub lock to lock to check for any tight ball joints


Linky to bearing. You need the 1".
I found that my MK supplied shortened rack hadn't been greased I fitted a grease nipple to centre section, it took nearly a full cartridge to fill it, to say it made a difference is an understatement.

[Edited on 26-3-11 by 40inches]


Macbeast - 26/3/11 at 11:15 AM

@40inches
Many thanks. I assume the SLF 1 and that the SLF1EC is the same but with a dirt-excluding cap ?


40inches - 26/3/11 at 01:04 PM

quote:
Originally posted by Macbeast
@40inches
Many thanks. I assume the SLF1 and that the SLF1EC is the same but with a dirt-excluding cap ?


No, the SFL1 has a built in locking collar(the one you want) the EC has a separate collar


mad4x4 - 26/3/11 at 02:16 PM

This links in with the MK indy self centre thread that was also started today

linky to other Similar thread


Mark Allanson - 26/3/11 at 03:57 PM

quote:
Originally posted by panichat
Mark (Allason)
Can you give the details of your redesign for the wishbones?

I did the bearing mod to replace the sierra column bearing, but didn't make a lot of difference.

I guess the perfect outcome would be a diagram that gives the relative position of the upper bj and the lower bj for perfect steering.
Thanks
Dave


See this, andthis


Macbeast - 26/3/11 at 05:20 PM

@ 40inches - many thanks - ordered.