Knowing that I'd already failed because of the exhaust was a huge help today - I slept well, and wasn't at all nervous. The test itself was very fair, and the tester was as helpful as he's allowed to be. When the times came where a little tweak would mean the difference between a pass and a fail, he'd point it out and then wander off to look at some other bit of the car whilst I fixed it

However, there were a few things that weren't fixable:


A glorious and comprehensive fail. The tester thought that something "must be wrong with your cat" - CO was 10x too high, and HCO 50% too high. Lambda was oscillating wildly, but always just slightly outside the allowable range I didn't bother to tell him that the thing wrong with the cat was that there might not be completely 100% one actually in the exhaust at all.


He wouldn't buy my feeble story about the bottom edge of the dash being where it met the (correctly radiused) cross chassis member, but insisted that it was where I'd bent the dash over to meet it (I realise that this is hard to visualise, but the bend is at 45 degrees, joining the vertical dash face to the horizontal tube.

Then he hmmm'd and haw'd about the trim around the bike clocks. He thought my stick on foam (which I'd used to cover up the dangerously rough edges) was neat, but he couldn't bring himself to say that it was like a manufacturer would use. Then he could. Then he couldn't. Then he went for a second opinion. Ultimately, he failed them.

There was also 1 push button switch he didn't like. I would have argued (given that it had a soft cover, and retracts when you push it (it's a push button, after all...) but the bottom edge radius and clocks mean I'm making a new dash anyway, so there was no point.


My centre mirror is mounted to the inner surface of the top tube of the roll cage - safe I thought! But the arm that goes 'twixt rollcage and mirror was contactable by the virtual pedestrian flying over the rollcage, and was failed - needs a rubber boot. He let me turn it upside down, to see if that helped - but it was worse...

The rims of the front wheels project 10mm beyond the body plan - (you sort of have to imagine the car without tyres on, and then drop a vertical line from the bodywork down to the rim). In the post SVA diagnosis, Ian and I concluded this must be due to the offset on the Barnby wheels being bigger than usual. There is no fix for this - I'll need to borrow someone else's wheels for the next test

The bonnet vent edges need to be blunted

The aeroscreen edges weren't uniformly 2.5mm radius - sometimes only 2mm. Curse my shaky Dremel hand... The fix is to stick some trim around the edge

Fuel filler cap insecure - doh! The collar I'd made didn't fool him I'll need to rivet it in for the re-test.

Cables - he didn't like at all the way that I've glassed in the wires around the bodywork, feeling that the edges of the glass fibre could chafe the loom tape I'd put on the wires, and then the wires themselves. In retrospect, I'm inclined to agree

Fuel tank - judged insecure and subject to vibration. Well. OK. You got me there - it does wiggle about a bit. I'd always known it was suspect, hence the luggage straps to add a bit more security. I'd figured that so long as it couldn't jump out of the car it would be OK, but the tested pointed out that it would gradually fret until it eventually wore through

Self centring steering

It doesn't. Not even slightly. Not a jot. Put it on full lock and let go the wheel, and full lock is where it stays. In the post SVA post mortem, Ian was mystified. How had I checked my toe-in? 'By eye.' I said. 'By eye?!' 'Well, with a long bit of angle.' 'Let's use the gauge, shall we. We're looking for something like 3/16" on this scale. You've got, ahm (fiddle, fiddle), hmmm - the scale doesn't go that far, so you've got more than an inch. Steering been a bit heavy has it?' 'Maybe.'

So, we fixed the toe, and the car now self centres. Magic. The back is OK overall for toe, but I've got to do some magic trick with string to make sure that it's symmetrical.

So - I jolly well deserved to fail on the dodgy fuel tank straps, and the lack of anti-chafing protection for the wires attached to the bodywork, and the rubbish toe assessment method. Emissions esmissions, pah. And the radiusing is just annoying - none of it is actually dangerous. IMHO

The car weighed in at 628kg with 45 litres of fuel and 150kg of passengers, which comes out to a Caterham weight of 438kg - heavier than I wanted, but not too bad. Weight distribution is 53/47 back/front without driver, and 61/39 with.

Observations from the driving to and from the SVA:

  • The CBTech dash has decided that 0 oil pressure is actually 2psi - need a bit of recalibration here
  • The rear body work flaps around a lot at speed - I'm going to have to work on some beefier way of attaching it to the chassis
  • The aeroscreen is mostly useless - it's much too low. At 70 mph, the air comes back almost horizontally, which is nose height. The next version is going to be a good deal taller, and may have a little lip at the top as well.
  • The fuel level indicated on teh CBTech dash is always 0 - not really a problem, except that it meant the high brightness warning light was on continously, meaning that I got no indication if any of the other inputs went out of range...
  • There's something wrong with the built in Suzuki fuel level light - it too is also always on!


This page last updated on: Sunday, Jul 16 2006