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wow - thread revival! Craig hasn't had the car for years now and doesn't get on here anymore. The car still had the standard steering box.

Not sure what you mean by "its make the box easyly free hmm", but it had nothing to do with the fact its steering box instead of rack. Sounds like you have too much freeplay which means wear in some of the steering components.

More track= fwd offset wheels= gay

hey there did u still using stock steering box or change it to rack already ?? i using it also but the its make the box easyly free hmm

I agree with moving the strut top inwards also. This will be happenning thanks to some adjustable strut tops I am getting made up. Looking to be able to get around the 4deg mark if needs be. Fingers crossed on the bump steer issue. The suspension arm ( I assume you are talking about the strut) is pretty long when connected up to the S13 spindle so hopefully I won't have too many problems. I'll let everyone know how it drives when I have it on the road.

Craig

Hiya NoPSI.
Sounds like a damn fine swap.
My 2 cents worth, the bottom arm needs to be the same length as the steering arm, otherwise , as Erol pointed out, you'll get bumpsteer that you cant fix with spacers.

Moving the holes in the crossmember outwards may mean you end up with a steering arm longer than the suspension arm, and no good will come of this! (try fixing bumpsteer in a mini some day)

Consider moving the top of the strut inwards to give yourself more camber, it doesnt give you as much increased track, and wont mess your bumpsteer around as much..

Having said all this, bumpsteer is usually the last thing to get tuned out of any circuit car, and with the high spring rates and limited suspension travel involved, doesnt make as much difference as on say a gravel car...

A little forethought now however can save you a lot of grief later!!

The rear is std. Adjustable spring platforms and spring tops were added to the shocks. The factory leaves (minus 1 leaf) are used to locate the differential.

Spring rates are yet to be decided. The front is running some springs that were lying around the factory and there are no coilover springs in the back yet. That is what shall be involved in the testing when it is rego'd.

Craig

What LBS spring rates are you using in the rear and front .. Did you make a 5 link rear ?

I look forward to hearing how it goes on track.

Firstly the drilling of the lower control arm points. For street use the drilling would only mean enlarging the holes to accept the S13bolts. I however moved them out a fraction to create some more camber for track work. They are still on the same horizontal axis and the castor that the factory bolt holes have is till the same even though I have moved them out.

Secondly the FWD offset issue. I dont't see too many problems here as the silvia runs very close to this offset from the factory. As I am using pretty much a complete silvia front assembly I see no reason why it will be too bump steery to drive.

I shall keep you updated on how it drives once I begin some suspension testing. We can theorise all we want here on the net but on the track is where I will get my answers.

Craig

NoPsi,
Two things stand out to me in your post. First is the drilling the pivot points for the lower arms. How has this changed the relationship of the arcs described by the lower control arms and the steering arms. If the arm pivots are not concentric, you generate bump steer when there is vertical suspension movement.

Secondly - Using FWD rims to solve a clearance or track problem is not the best solution. Rim offset and rim diameter change can have dramatic handling effects through changes in scrub radius.

For 0 scrub radius, the tyre contact patch centre should be at the same point on the road surface as the extended strut axis from upper pivot through ball joint to the road surface

You can make small changes to scrub radius with positive results to steering behaviour, but like a lot of things a little can be good and a little bit more disastrous!