A mixed day, 3rd outright and 1st in class (and first tin top) was a very good result, but had two incidences of the injector o-rings coming off again 😦
Fixed it once, then got a run in before it did it again. So the day ended early, but the lap was good enough. On the last run that I did (when it broke) the handling was much better – so there was more time in it…
As is the way with me, after having plenty of time to get the car ready for Waneroo, I’ve now run out of time again. All because of the addiction of going faster….
On previous events, the air intake temperature (temp of air going into motor) was much higher than what you want to see. There were two possible reasons for it – One was that I’d not made any ducting to force more air through the intercooler, and secondly that the air filter is in a location near the exhaust, and I never got around to finishing the box around it to keep the hot exhaust air away from it. The ducting into the intercooler is done and pending time over the next few nights, I want to re-locate the air filter as well, to put it in a better location (hindsight is a wonderful thing :))
Looking into the duct.
From the side.
Next on the list was to make some improvements to the drivers door. One is due to the fact that I’ve cut so much out of it that its really floppy now, and doesn’t want to shut very well. The second one is to make it a little bit safer. While I know that its a bit late to have come to this realization, but my recent overnight trip to Sydney made me think out things a bit different. Sophie was very upset because I was not there to read her a story and say goodnight, and by the time that I got out of the presentation that I went to they were already asleep. I’ve never really worried about me dying, and I never really thought that the kids would miss me that much – I’m at work for most of the time that they are awake. So I guess as I’m more important to them (than I am to myself) I really need to spend some more time making the car as safe as it can be in an accident. So to stop the floppy door syndrome, and to make it safer in a side impact the door is now filled with 120mm thick foam across the whole door, and there is now an internal skin that is a lot more structural than the standard door trim. The idea is that in a side impact, the foam in the door crushing against the roll-cage will absorb some of the impact, rather than the metal skin of the door just instantly crushing. Hopefully I never have to test it out, but if I do, at least I’ve done all that I can to make it safer.
The door weighs in at 15kg though – not too happy about that. The next version needs to be safe, but lighter 🙂
The reflections from the inner skin make it look all warped…
The skin is rolled over at the top – again no sharp corners are safer…
I finished off the passenger side of the rear diffuser (aerodynamics) so the outer strakes are finished now (apart from paint). At some point I need to make one or two more strakes for the middle section.
JC asked me the other day as to what was inside of the lower A-Pillar section of the car. I didn’t know, but its been on the list of things to remove from the car for some time, so I cut it open to see what was in there. The answer is not much……..
And it only took about 900 grams out of the car 😦 So JC, the answer is very little!
After that it was a lot of items that were not really photo worthy – like changing spark plugs, changing the diff oil, putting a new battery in, cleaning the inside of the car, re-assembling the removable firewall section, putting the rear window back in, putting the front bumper and fenders on, putting the new fire ext in, etc, etc, etc……
Last night I had to change the oil in the car, so I either needed to cut a hole in the floor or take the floor off (the floor completely covers the bottom of the motor, where you drain the oil out of). So I undid the bolts holding the floor on, but the floor also attaches to the front bumper. Then it was either take the 8 bolts off that hold the fenders and bumpers on, or the 12+ screws and glue that hold the floor to the front splitter. So funnily enough it was easier to just take the whole front off the car…..
And this is what you are left with. A front end in one piece (sort of). The next project that I want to do it to take a mold of this whole front and make a one piece fibreglass end for it. The parts here are heavy in most cases, and that whole thing weighed a lot more than I was expecting.
So I’ll see how I go after waneroo as to if I can get a start on this one piece front clip.
Another angle:
Got all the injectors and parts back in the car last night, and got it run up on the dyno.
Its still running, and still producing the same peak power, so it’s looking like I got lucky and the motor has not been destroyed.
While its a good thing, I was liking the idea of putting something different in, like a Nissan VK56 motor…..
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!
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:
A quick video from under the bonnet of the car at Jack’s Hill. This is the run where the car stopped 😦
http://members.iinet.net.au/~mikejoss/Run1.avi
Still, its interesting to look at the tyres and suspension working.
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…
I’ve cut up the old steering column and re-made it. The angles on the uni joints are now equal, so it should take out the harder to turn spots as you go from lock to lock. Should lead to steering that feels more comfortable for me – and that confidence = speed. :). In rotating the front wheels by hand, the steering wheel now spins at a constant speed – before you could see the wheel accelerate, then slow, then accelerate again.
Its just all tacked together at the moment, need to get more gas for the welder to continue… Also want to put the car back on the ground and test it under load to make sure that I’ve got it right this time.
Also got one of the fibreglass front guard mounted on the car. With white front guards she’s looking like a real bunky now 🙂
The rest of the weekend was moving rocks, mowing lawns, gardening, making cages for animals, cleaning up / cutting up old metal around the place (ok, around the shed) ready for a trip to the scrap metal yard to get rid of it all.
So, though I’d talk to myself about the things to clean up on the car before the next event.
On the list is:
Probably a lot more too, but that’s the plan for now…
We had a decent event, on a hillclimb that was fun to drive. All day could not get enough rear end traction, and at the end of the day we lost out to a few of the 4wd cars. So 6th outright (0.05 seconds away from 3rd :/) and 1st in class was all that we could manage.
As usual, lots of things to do different for next year, in terms of car setup etc.
Albany, 6.30 am, hail, thunder, lightning, and heavy rain, what a great way to start a day of motor sport!
Luckily, the last of the front passed over at 7.30 and after that it became a beautiful 20 degree day.
For practice the road was still very wet, was impressed how well a full set if slicks still gripped in these conditions, I thought it was going to be too wet for them.
By the first run it was almost 100% dry, so it was game on.
First run was a 36.5, fastest outright by 2 seconds, going OK so far. I knew this would not last as the others grew in confidence, but I was happy with that for my first ever run here.
Ended up finishing the day with a time that would have won last year 😦 With some faster cars here this year, I still managed to get 2nd outright and to win my class.
So in all it ended up being a good day.
While in the shed doing some more cleaning up, the old rear wing was sitting on the shelf – I wonder if it would work on the front for Albany?
It does look a bit gay, but if it makes the car faster……
Hmm, no, I’m not sure that I can do this…..
Maybe I’ll make a front splitter instead and see if that gets me the front end downforce that I need to balance the car out.
One day its going to happen (a wing on the front), but maybe not now.
After the race to get the rear end of the car chopped off, a new frame, firewall, fuel tank, etc etc all built – I had made quite a mess….
So spent some time after work and over the weekend at night to clean up. It took a total of 14hrs!!! Yes, the mess was that big…
I also re-organised a few things to make better use of the space around the middle of the shed – ready for the next car build 🙂
Added a shelf for the Tig welder to go on, to keep it off the floor and off he bench when I am working on larger peices.
Added some more shelves to the wall to put the containers of nuts and bolts, mounted the spray guns on the wall, plus lots of other little bits that I had planned to do a year ago.
Just a random shot….
Now, the next job is to get ready for the Albany events, and for this I need to make some storage space on the trailer – so its time to mess the shed up again 🙂
The day didn’t start well. Race car battery was flat. No Probs, just get the jump pack – flat too…
So after getting the road car down to the shed to jump the race car – can’t find the jumper leads… Used some large cable, the earth lead from the welder and some vice grips got it all hooked up and the car started. Jo put the road car away while I loaded the race car. Then I stalled it half way onto the trailer. Had to go get the road car, jump it again, etc….
Then tore the front splitter off getting it onto the trailer.
At this point, thinking great – what a day….
Out on the track, the car was fairly good. Just struggled all day with the front end not having enough grip.
After some suspension and wheel alignment changes for the last run, I finally had enough front end grip to push. It was still far from perfect, but it was much better than it had been. If only I had not torn the front splitter off it may have had the front end that I needed…..
Ended up with a 60.4. A good time for the first ever run with the car in its current state. Its funny to think that the first time I went to Waneroo with the Silvia as a fairly normal car and did a 65 second lap, and that was fast for a normal car! In this game, a 5 second per lap improvement is massive.
The new fuel tank needed a new fuel filler.
I made this one out of some pieces of alloy tube, some plate and a welder 🙂
Next up was making a new rear window – out of lexan again.
Here is the first mock-up of the fuel filler in the window. Still needs paint.
More soon…
Wow, where to start this week….. So many things have been done recently.
I’ve cut out a section of the front bumper, and raised it up higher. This creates a diverging ramp under the nose of the car, speeding up the airflow creating a low pressure under the car, sucking it to the ground (well that’s the theory anyway!)
These next two pics show the ramp a little bit more clearly.
The sections in front the wheels stay low to the ground, to divert the airflow around the front tyres, reducing drag.
It was then time to keep working on the rear floor, making supports to hold the floor up. Now that there is nothing left in the back of the car, I had to make mounts that connect the floor to the chassis.
This one is to hold up the back edge of the diffuser.
These ones are to mount the other end of the diffuser, just in front of the back wheels,
Next on the list of things to do is to build the new firewall. This will be a new section behind the drivers seat – think of the inside of a single cab ute. This will seal off the passenger compartment from the fuel tank, exhaust, diff etc that is now exposed in the rear of the car.
The middle upper section will be clear (lexan to be precise), and due to the complex nature of the roll cage it was too difficult to make a single lexan sheet that would span the whole width of the car. So instead i made two side panels to go around the bars from one side, then the lexan can join these panels from the other side.
The next step was to make the lexan panel. After cutting it all out, I painted the outer edge black, where it would be glued and bolted to the car.
The next item on the list was a new fuel tank. I wanted to build a new tank that was lighter and would not fuel surge even with as little as 1/2 a litre of fuel left.
When I built the last tank I was still driving the car to places like Collie for events, so it was sized accordingly (28L to be exact). Now that its a trailer queen, it only needs 8-10 litres max to complete 5 laps at Waneroo.
Here is the first part of the tank. The tube is to ensure that there is no surge, with the larger part at the top to ensure sufficient capacity.
The bottom section in more detail. The bottom outlet is the feed to the fuel pump, the upper one is the return from the motor. These outlets are spaced out to make sure the fuel stays as cool as possible (the fuel returning from the motor has been heated from the heat in the engine bay), but at the same time making sure that the fuel being returned to the tank can’t get caught in a corner of the fuel tank that is not near the fuel outlet. Yes, trying for the best of both worlds again.
My welding on alloy is getting better and better all the time too. 🙂
This is how the tank will sit in the car.
Had to re-jig the fuel lines as well. The tank is now a lot closer to the front of the car now, so I had to shorten them all.
One last view inside the tank before the top goes on.
Wow, I’m tired after that post!
Been working the new floor. For the next event there will be a new front and rear sections.
The front end I’m going a different direction to where I was headed, and the rear end was just the old one from 2010 that I plonked back on.
The new rear floor is much wider than the old one, and tucks in much closer to the rear wheels / suspension.
Its a bit hard to tell, but this the new front, the centre section is raised at the front, to channel air under the car, sucking it to the ground.
You can see here how much wider this new one is compared to the old one. I covers the suspension arms etc, attempting to keep the air flow under here clean.
…gives you wings apparently. In my case 1/2 of the Anzac day holiday gave me a wing…
This first pic is from inside the boot. The wing needs something strong to push down onto – if you want to take full advantage of it. So its mounted into the rear subframe, where all the suspension is mounted. The idea is that every gram of down force that this thing produces gets fed straight to pushing the tyres onto the road – rather than the force going into flexing the rear body work.
And the other side.
Close up. This shows the mounting plate where the alloy strut (see pics a bit lower down this post) mounts to the car. It bolts on under here so that it can be removed if required – but it keeps the bolt heads etc out of the air flow.
Here are the alloy struts. They go through the boot lid and attach to the mounts shown above. I choose to do it this way to keep all of the mounts etc out of the air flow that is running over the car.
There is a single hole at the rear edge of the wing, where it can pivot. The holes in the front edge allows the angle of the wing to be changed, meaning that I can create more or less downforce as required. This change may be based on circuit characteristics or just to even out the balance of the car i.e if the back is sliding at speed, I can add more angle, and therefore more downforce to the rear to balance it out.
With the wing sitting in place, set about about half way through its range of adjustment.
A shot from further back, so better see the scale of the wing in proportion to the car. I’m not sure if I haven’t gone too far rearwards with the wing to make it look right. We will see when the wheels are back on and its out of the shed.
LOTS more to do before Wanneroo! I did a list last night of the things remaining to be done – its a little scary…
Mike Joss Racing 