Sunday 7 October 2007

Front Setup.

With the rear sorted I turned my attention to the front. First up the front camber.
I had followed GD's video and used a 1/4" spacer at the top wishbone mount. When measured this proved to give slight +ve camber.

So I removed the 1/4" spacer and changed for 2x2mm spacers giving 4mm. This gave me a slightly better result and I had negative camber.

Correct camber is 0 - 1° negative, so Im going to leave at this for now.

With camber sorted I figured caster should be next so again I used a tip from Simon's build and also used his caster template.

Here I figure I have about 4.5° caster, GD manual say about 4° so I will see how I go with 4.5°.

Happily the other side was the same.

With camber and caster sorted I moved on to set the front toe. Step one center the rack by following GD's rotation and count method. No problem there.

Then clamp a 1m length of angle to each disc.

Measure the distance at front of the angle and then at the rear, rear minus front equals toe in.

After a bit of rotation of the tie rods I managed to get the toe within the required range of 0 - 1.5mm overal. My actual measurement is 0.812mm.

I noticed whilst doing this that the toe was changing oddly as I rotated the tie rods, after a bit of head scratching and a call to Simon we settled on the rack moving. So to stop this I inserted the steering rod to the rack UJ and clamped it down. Problem solved.


So thats the toe correct but which way are my wheels pointing. So to find out I clamped the laser level to the front disc and aimed it at the angle which was clamped over the rear axle with the chassis centerline marks aligned.

I could then mark off the front wheel alignment on each side and measure the distance between the two laser marks. The center of these two laser marks was plotted on the bar and the distance from this new centerline to the chassis center line was measured giving the aligment "error".

I then decided the best way for me to bring the alignment true was to divide the error by 2 and one one side add this distance to my plotted point and on the other side deduct it from the plotted point. Hnce giving me two Target points for the laser marks.

On the picture below S is the firts plotted point and T2 is my target for the alignment to be correct. (T is the first attempt were I went a bit wrong!!)

So all I did was wind the two tie rods until my laser lined up on the T2 points.

I rechecked the front toe and it was spot on so, all wheels pointing the correct way with front and rear toe in correct.

The final thing to set was the bump steer. Again GD's method was followed and a 1m bar placed on the floor under the one on the disc.

Here we are at "ride height" the floor bar corrected to be level with the disc bar.

Going through the full range I noticed a slight bump steer effect in full bump.

Measuring the actual range that this effect started to take place shows it to be over the last 1/2 to 1" of travel. I attempted to resolve the bump steer by moving the rack but I could not eliminate it as my rack was already at its maximum adjustment position. If this becomes a problem on the road Ill reset the steering with the rack in the mid position to give some adjustment.

So Im happy thats all sorted. I fitted the final two wheels and rolled it out into the sun for the first time!(Blogspot posting system is really screwed today, each picture I insert adds about 5 carriage returns to each line of the post!)

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