Wednesday, 23 December 2009

Body Arrival

Well woke up this morning full of cold and looked out the window to this.

Fortunately not to bad so popped along to the van hire place to pick up the Luton.

Luton Van

4m long x 2m wide so body should fit just nicely.

While I was at GD I nipped upstairs and took a couple of photos of the body being made, I was lucky that the one in the moulds was the same colour as mine (Copy Cat)Wink

Mould 1

It really is a thorough process. The jigs holding the moulds look as substantial as my chassis, so not much chance of any movement there

Mould 2

So after a quick drive back I was the proud owner of a RAL 5004 GD427 Body.

The body looks fantastic. A superb finish straight out of the mould. The colour is brilliant too, blue in some lights and black in others, just what I was hoping. Once it’s got the bright work on and been decked out in some nice sumptuous leather I reckon it’ll be a real head turnerDancing

Right off to the garage now for a couple of weeks to get sanded and polished up.

Tuesday, 15 December 2009

!! Great News !!


Andy from GD called today to tell me the engine mounts are ready………. and wait for it……………



I told him he was just like Santa and he said he’s going to wrap it with a big bow and everything.

I’ve booked the van and will pick it up on Monday. So it’ll be out with the wet and dry over Christmas to get all the shut lines done, gel coat the engine bay, cut the holes and polish.  Party

Sunday, 6 December 2009

Body Shell Colour

!! Stop Press !! After much deliberation I have decided to go with RAL 5004 Black Blue for the gel coat colour. Not listening


I know it’s pretty boring but I just bring myself to be more adventurous and went with what I’d seen already and liked. Peace Sign

I actually ordered the body a few weeks ago and Andy said there could be a chance I’d get it before Christmas. I’m not going to hold my breath though as he has said he is quite busy with a couple of GDT70 to get out among others.

Front End Round Two

After my less than pleasing outcome to the finish of the front end build I have now stripped it all back down and redone all the geometry. I am pleased to report that I now have all wheels present and accounted for.
Toe in 1mm overall….Camber 1/2 degree negative both wheels….Castor 4 1/4 degrees….Full Droop to Full Bump about 5mm projected over 3 metres.
All measurements are well with in recommended guidelines. I’m still unsure of exactly went wrong the first time around, but it’s all sorted now so I can sleep at night
While I was at it I set the front hub end float and checked the disk run out.
Everything was ok here so it was just a case of fitting the locking washer and split pin.
Then the dust cap followed by the wheel and repeat for the other side.
Well not much else to do now until Andy sorts out the engine mounts.

Friday, 4 December 2009

Let The Wagon Roll (Well Not Quite)

The final job on the front suspension was to fitted the shock absorbers  and finish off the brake pipes.


Four Wheels & Rolling


But hang on a minute something is not quite right. N/S front looks OK, O/S front is toeing out quite dramatically, Now that cant be right. Crying

Not quite sure what has happened but after a bit of research on other build sites one of the things that is wrong is my calculation / method for making sure the front wheels are facing in the right direction.

So it of with the wheels tomorrow and start again.
Hey Ho I’m sure there will be plenty more of head scratching moments I dont know

Thursday, 3 December 2009

The Dreaded Bump Steer

Now I’m not sure why but I wasn’t really looking forward to this bit. I had read with interest Simons detailed account of setting bump steer using magic and mirrors and also looked at the GD method as described in the video and in the build manual. In the end I decided on a slight adaptation of this one by one of the Cobra Club members.
I started by taking a piece of angle and drilling a hole in it centrally. I then placed this on the stub axle with a packer washer behind and tightened it up.
Next I placed the laser level on the angle and checked the chassis was level in all directions as well as the laser level.
You then need to place a piece of paper 3m away at a height where the laser will hit it, making sure it is vertical or as I did just draw a vertical line on it using a spirit level. The suspension is then set at ride height determined by the top wishbone being horizontal. I then plotted this point where the laser hit.
.Using a trolley jack under the axle you can then jack it through full droop to full bump and back again noting the movement of toe in / toe out as the laser dot moves with reference to your marked vertical line and plotting it.
It is then just a case of moving the steering rack up or down to bring the dot as close to the vertical line as possible as shown in the video below:

Now I am not sure how accurate this is and if my method is correct but I would welcome any comments or suggestions. And yes I do realise that I’ve spelt height wrong on the piece of paper. No excuse really it was late and I didn’t have my spellchecker working at the time.

More Front Steering Geometry & Steering Rack

I fitted the steering rack to the slotted mounts on the chassis. Andy supplies the rack with polyurethane bushes which are already split so they just pop straight on. The track rod ends are then screwed on and inserted into GD’s supplied new steering arms



Once the rack was fitted it needed to be centered, this is done by marking the input shaft and setting a datum on the steering rack with the aid of some masking tape. I counted the number of turns from full right lock and marked it then back to full left lock and mark it. Then turn the rack back to 1/2 the number of turns between the marks.


So the next job on the list was to set the toe in. I did this by clamping a 1m long piece of angle to each disc face and then measuring the front and back of the angle then subtracting the rear measurement from the front to give me a toe in/out figure


Our friends at GD recommend 0mm to 1.5mm toe in overall , so it was just a case of winding the track rods in or out until the required toe in was obtained.

Well now I have the correct toe in, but which way are the wheels facing. For this it was back to my trusty bit of angle clamped to the centerline of the chassis as marked when setting the rear axle up.


With the laser level clamped to the disc I marked the red dot on the angle, then repeated it on the other side. I then measured the distance between the two marked points and marked the centre of that on the angle. I then moved the angle so the centerlines on the angle and the chassis corresponded and adjusted the track rods until the laser came back to the marks made on the angle. Now we have all wheels pointing in the right direction.

Thinking I Hope Thinking


Front Suspension Set Up

I at last got the wishbone sleeves back from Wards and guess what they were still to tight except for one. I decided that I would break out the emery cloth and rub the shafts down a bit, 10 minutes later they were a nice snug fit.

The build up of the wishbones is pretty straight forward remembering to use copper grease which should help to stop any squeaking and aid smooth movement.


Once all the ball joints were torqued up it was time to set the camber. The GD recommendations for this are 0 degree to 1 degree negative. I added a 1/4” shims to give it a mean angle and then adjusted it by adding removing shims to get the required result.

DSC01390About 1/2 degree negative


To set the caster shims were added or removed to the top ball joint.


Caster is required to make the wheel follow a straight line without assistance and create self centering. The angle required is between 3 degrees and 5 degrees. I used Simons very handy template for this operation. It can be found here. I’m not sure what I and doubtless many other GD builders would do without Simons site.


As you can see with the template placed up against the disc brake lugs which conveniently represent a line parallel to the steering axis I have managed to get a caster angle of 4 degrees.