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MK indy self centering
DIY Si - 4/7/06 at 06:27 PM

Following the recent thread in the mk section, does anyone make a set of top bones that sort the centering problem with the indy? I would rather have correct bones rather than fit springs. It's 'ok' as is, but I would feel much more confident in her if she behaved a little better. Gets a bit too lively on the local bumpy roads. I could make some, but if they are some nice cheap ones available......

John Bonnett - 4/7/06 at 06:33 PM

I had the same trouble with my Dellow. The problem was insufficient caster angle. The car sails about and feels straightline unstable.

John

DIY Si - 4/7/06 at 06:43 PM

I know. I could fix it by making new bones with 7-8 degrees of castor, but if someone makes some for a nice locost price I'll buy them.

nitram38 - 4/7/06 at 07:19 PM

It only took me 2 hours to remake mine.

donut - 4/7/06 at 07:31 PM

My Indy has 0.5 digrees of neg camber and 1 digree toe out and it self centers!!

t.j. - 4/7/06 at 07:36 PM

quote:
Originally posted by DIY Si
I know. I could fix it by making new bones with 7-8 degrees of castor, but if someone makes some for a nice locost price I'll buy them.


I don't understand why there is so much castor needed. 5- 5,5 degr must be enough. Is it due the lack of presure on the front?

Maybe you should go for max. 195 mm tyres? 1,2-1,5 bar tyre presure?

DIY Si - 4/7/06 at 07:39 PM

Already on 195's and the pressure's right. Or was on sat. When I look down from above there seems to be very little in the way of castor.
Nitram; did you make completely new bones, or re-use the old bush tubes?

nitram38 - 4/7/06 at 09:03 PM

I made completely new bones as it was simpler. I have rod ends instead of ball joints and bushes. A mate of mine knocked up threaded inserts for the rod ends.
I just drew the upright on paper and applied 7 degrees to the centres of the bottom rod end. Where this line intersected the top ball joint horizontal line, I took a measurement.
I just got a piece of wood and some angle iron brackets to mark out the insert centres and bolted the inserts in place. I then just cut 2 tubes to fit and welded them.
I am lucky with my inboard mounts as they were originally bushes so I used packing washers either side of the rod end. This will give me the option to increase/decrease castor.
The car centres well and is not bad on the steering wheel effort considering that my rack is 1 1/4 turns lock to lock!
The sva man said that it need not centre as well as it did........go figure. He even suggested removing some castor, but for now it feels ok.
At 3.5 degrees my car did not centre, at 7 it does.
For sva your steering only has to attempt to center to pass, but I prefer castor working properly as the car is stable at speed and does not wander.
The toe out method is not good for anything but passing sva and could make your car jittery when removed afterwards.
I was advised to do it the correct way and I am glad I did.

DIY Si - 5/7/06 at 03:07 PM

Looks like I might have to make some new top bones then! The car's already sva'd, but I find it wnaders a lot on the local roads, which are a tad bumpy in places. It makes driving for any great distance a bit tiring as you can't realy relax into it.

JoelP - 5/7/06 at 03:12 PM

i am in the middle of this process myself. I am also changing both the transit top joint and the track rod end for rosejoints. Ive ordered it all from nick skidmore, including the inserts which he makes. Approximately £30 in roses and inserts, i just need some seamless tube now. Im sure it could be done with erw anyway, but the inserts wouldnt fit as well.

By using roses as nitram suggests, you can both pack the brackets out (i'll use lock nuts myself) and screw the roses in and out to adjust castor.

My car currently has negative castor and its dangerous on uneven roads.

Keep us posted on progress!