Month: July 2012

Another day, another dollar – spent.

The jobs for today were supposed to be putting more of car back together.  That was too boring so I started pulling more things apart instead.

One of the first things was to pull out the accelerator pedal and make some changes to it.  The pedals that I build were quite close together, as there is limited foot space with the motor pushed back so far.  I have now had 3 cases where I’ve hit the accelerator with the side of my foot when going for the brake – the worst one at wanneroo at 190km/hr that made me run off the track, over the sand and almost into the wall, were it not for a rally style flick in the dirt to get the car to turn parallel to the wall, just before I was going to hit it.

So, the pedal came out and I modified it to move it further to the right, away from the brake.  As it turns out, there was plenty of space left in this area so it was an easy change.

Next, I was supposed to finish cleaning out the inside of the car – that was too boring so I cut the drivers side door up and made a lexan (plastic) window instead.  The door is now 1/2 the weight that it was.  I still need to fill it with foam and make an inner panel for it (for crash protection)

 

Its not perfect, the next one needs to be better, but I did learn a lot from it.

This is the new door opener.  Nice light bit of alloy.  The same handle can be used from inside and outside of the car.

Next on the list was to clean up all the wiring and other items under the dash, and make a new mount to hold the center console, as the dash cover is now gone.  But again that wasn’t sounding too interesting, so I made more changes to the rear aerodynamics – difuser strakes.

For the rear difuser to work well, it needs to have the airflow in it flowing in a nice straight line.  Things like rear wheels spinning nearby hurt this airflow, meaning that you don’t get the same levels of downforce.  On this years car I had not got as far as making these, so I started.

Looking from the side of the car, this fence keeps the air inside the tunnel separate from the swirling air that’s exiting behind the rear wheels.  The cut-out behind the wheel is to get the air that’s being picked up from the back edge of the tyre from being pushed up into the top of the wheel arch – creating lift – which is bad for aero performance.

 

From underneath the car you can see the fence that’s separating the tyres from the tunnel.

Once I have a setup that I am happy with the performance of, I’m going to make a fibreglass version out of a single piece, to make sure that its all smooth.  Having rivets etc sticking out is not good for air flow.

Some more veiws, this first one from the rear of the car looking at the tunnel to the back of the rear tyre.

 

Another side view

 

After that the night was getting on, the F1 race had finished and it was time to leave the shed and go to bed.  That was lucky, cause next on the list was some more boring stuff!

 

 

Sunday’s Toil

Didn’t get much car time today, just did some work cleaning up inside the rear of the car.

Popped the rear window out to make it a bit easier to work on.  Then there was lots of grinding and sanding to clean up all of the rough cutting that I did when tubing the rear of the car, then ran out of time to finish it off nicely.

Then, while the grinder was out, I cut off the rear guards and bumper getting reading for finishing the aero on the rear of the car – around the diffuser.  These cut sections will meet into the side strakes of the difusser – this will make more sense when its done and I take a picture of it 🙂

When the rear is done, it will look something like this on the sides:

Jacks Hill – Not the best of days…

Hillclimb at Jack’s hill last weekend, did a practice run, talking it a bit easy, just putting heat into everything.  First timed run ended about 1/2 way through with a bad miss-fire and then the motor stopped and locked solid.  😦

Couldn’t get it to start again, motor would not turn over by hand either.  Not a good sign…

Packed it onto the trailer and took it home.  At home discovered the 4th cylinder was full of fuel.  Removing the injectors show that the bottom o-ring has failed, allowing fuel to fill the cylinder.  As the RPM was very low when it stopped, the motor may be ok, but there is a chance that its bend a rod.  Compression tests fine, so at this stage I’m just hoping its ok.

I’ve ordered new o-rings for all injectors, and I’m getting them tested while they are out to make sure they are all ok and are flowing evenly.

When the injectors come back I’ll chuck them back in and she’ll go on the dyno and we’ll see if it’s ok, or if it blows up…