2 August 2009
4 hours
The SVA - Single Vehicle Aproval has now been replaced with the IVA - Independant Vehicle Aproval. The main reasons for the changes is to cater for kit cars produced professionally by small scale manufacturers. The professional build has to comply with more stringent standards then the SVA. For the individual building a kit car like myself the standards are about the SVA. However some opportunities have been taken to increase standards/requirements in some areas. At time of writing the areas that I am aware that effect the westfield are:
- 1. Exhaust noise limit lowered to 99 decibels at 3/4 power
- 2. fuel tank must be grounded to chassis
- 3. fuel filler cap must be tethered to the car
- 4. Master brake cylinder identification
- 5. Extra indicators to be installed on the cycle wings.
I tested my exhaust the other day and it came out at 97.8 which I was pleasant surprised at. So that's point 1 covered.
Point 2. Fuel tank grounding. This is an important safety issue one which I am extremely happy with. Amazing that this was not covered in the SVA. The westfield tank is ali and therefore a conductor of electricity. Furthermore the tank is places on closed cell foam on the chassis and the tank straps are also lined with closed cell foam. So effectively the tank is completely insulated. This is like a giant capacitor being able to store energy, electricity collected maybe from friction whilst driving along. This will build up and when does it ground, erm, when you fill up with fuel, no good! I measured the resistance between the tank and ground and it came out at 150kohm. To attach a wire to the tank I took a large jubliee clip and drilled a 3mm hole through it and then soldered the wire through the hole ensuring that a blob of soldered formed on both sides. I then filed down the solder on the inside yto make it flatter. See photo below.
Next I totally undone the jubiulee clip so that I could place around the outlet on the fuel tank without having to disconnect the fuel line. O nthe westfield fuel tank, the fuel outlet union is screwed into a large outlet on the tank which is about 35mm in diameter, perfect for the jubliee clip. Refer to the photo the swirl port, furthest corner away just about the silincer you will just make out the jubilee clip.
This wire can then be attached to the nearest convenient chassis point, as below. Now the resistance is a flat 0ohm.
Point 3 - tethered fuel filler cap, erm not so important I think but would constitute a fail if this was not done! If the filler cap uses the same key as the ignition and this key cannot be removed until the locked on the car then there is no need for the tether. Obviously the thinking behind this one is to preent you driving off and leaving your filler cap behind. So to do this take a bicycle brake cable and thread through one of the holes in the filler neck that is used to vent fuel. The lead on the end will prevent the cable being pulled out from the front. Now take a 6mm electrical ring terminal ones used for earths. Strip off the plastic insulator and then using a non-insulator crimping tool crimp over the brake cable. Make sure this is crimped and crimped and crimped really tight. Now bend the ring connector so that the cable is 90 degrees to the ring as shown below.
Next remove the 6mm nyloc nut that secures the spindle on the fuel filler cap. Remove the washer and replace with the ring connector. tighen up to the correct position to ensure that the cap seals when locked. I found that I could not use the washer as the bolt is only just long enough. See photo below.
I see the length of my tether so that if dropped it would my than likely hit the fog lamp rather than the body work.
I also sourced some convoluted tubing to place over my speed transducer, this fits completely over the bolt to protect from the elements a bit more.
Now that I believe that my dashboard will not have to come off again I torqued up the steering wheel bolt to the required 35 ft/lbs
5 August 2009
Session 305 - Wheel rolling circumference
I had previously calculated the rolling circumference of my rear tyres for purposes of calculating final drive calculations. These calculations would be required to calibrate the speedo. Of course the calculated rolling circumference is static and does not take into considering that the air pressure will change the rolling circumference! It will be close but maybe not close enough for correct speedo calculation. You will recall that I worked on the princple of my front tyres 205/50/15" having a rolling circmference of 1.84m which gives 3498 pulses per mile. Tonight I rolled the car on a flat surface. All I did was place a piece of masking tape on the tyre in the middle of the flat spot and then placed another piece of masking tape on the floor and marked the position. I then rolled until the mark on the tyre was in the middle of the flat spot and marked the floor with a second mark. I then measured the distance and it came out at 1781mm. So the tyre revolves 903.5 times per mile, 4 pulses per revolution gives 3614 pulses per mile.
I also need to check the rolling cirmference of my rear tyres which are 225/50/15". Repeating the method above I came to 1860mm. I have revised my gear ratio spreadsheet which can be found here
My dash2 relies on having the correct gear ratios and rolling circumference from the diriving wheels so that it can calculate what gear I am in for the display. I have therefore revised my dash2 config, which can be found here.
9 August 2009
Session 306 - IVA specifics continues
3 hours
Installed the side repeaters on the cycle wings today. Drilled a 6mm hole in the wing for the side repeaters which are self adhesive. Took the wheel off and used scotch tape to secure the wrire underneath then took out to the wingstays and covered with convulted tubing and fixed with cable ties. Followed the upper wishbone and took into the engine bay and split into the loom connector for the orignal side repeaters. I have been told that the original side repeaters should not be functional, all I have to do if this is true is disconnect the plug and the new side repeaters will still function.
See photo below showing the indicator illuminated. See the edge trim, this stuff I got from car builder solutions and it is brilliant, its very good quality, looks like plastic rather than rubber and still forms easily around curves and you can see. This edging also has a mastic type adhesive inside, you just press on and it stays.
I replaced my fuel filler hose with a free replacement from westfield. I spoke to them last week as the hose was a little on the short side.
I also painted the underside of the rear wheel arches with underseal protectant. Not necessary for the IVA but I wanted to get this done sooner rather than later whilst the arches are still quite clean. This will protect the GRP from stones which have been known to crack the gel coat on the outside.
22 August 2009
I think this is the first time time I have used the title miscellenous to decribe an entry in my build diary. With so little items to be done before the IVA its an accurate title.
I designed the lettering I want on the car the other day and sent the examples off to a car graphics company to get them made up in vinyl. Photo below shows on the left hand side the name of the brand; Westfield. Right hand side; 4.6 SEiGHT. The rollbar is sponsoring this website!
I am also having mine and the misses name printed to attach to the driver's and passenger's side, just under the mirrors. This might be a little chavy but I do think it counts a toy car!
Photo of driver's side:
Photo of passenger's side:
Nut covers for IVA installed on the front suspension components. Had to remove the track rod ends to get the rubber boots on, again an IVA requirement. Not sure how to cover the upper rosejoint as this is likely to fail as it is.On my little test drive I noted that the steering did not seem to self centre. Self centering steering is a requirement. So I checked the camber and measured the rosejoints position to make sure they were the same on both sides. Shock they were not the same despite the same number of threads showing, it seems that the threads start in different positions! Watch out for that one. I also had to cut one of the rosejoints down a bit as it would bottom out at the maximum camber setting that I have gone for. The camber is now set at 1.5 degrees negative.
I also had a simliar problem with the trackrod ends however with the steering rack you can undo the lock nuts and twist the rod to equalise. I hadn't realized this the first time I set it up.I was out by about 1mm but with my self centring issue I decided I must get it spot on. As part of this process I had ascertained the middle position of the steering and the steering wheel in the car was a little off-centre by about 3 splines. So yes I undone it and placed exactly central.
I need to find a solution to cover up the upper rosejoint and bolt and also the lock nut into the wishbone.
I noticed that my front brake pads vibrate at slow speed. Doing some searching on this topic reveals this is a common complaint with these calipers. The pads are held in place with a pin without springs. I bought some 3M anti-rattle self adhesive backing for the pads and installed. Seems to have done the trick. I used this on the rear brakes as the pads actually came with it.
23 August 2009
Session 308 - Front upper wishbone rosejoint - covering
Found a solution to covering up the top rosejoint. Involving cutting up a bicycle inner tube a couple of cable ties and some black insulation tape to cover up the ends. Hopefull the inspector will be happy with this.
Go to September 2009