Track Car Dreaming - NB-C

Snowmotion · Postby **Snowmotion** » Mon Oct 22, 2018 9:36 pm

With just 2 weeks between the OLT and the last round of the MX5 Cup for 2018 I had to be organised to get everything ready in time.
CAMS were super quick sending me me new licence and I was all ready to go.
I spent plenty of time going over the car to make sure every thing was just right.
I had been having trouble using Harry Lap timer consistently so bought a version of RaceChrono Pro for my Lenovo Tab 3. This had the added benifit of being able to link to my GoPro and start the recording from a screen in front of me instead of reaching back to turn it on.
I had previously stripped out the stereo so I decided to mount the Tablet inside the space where the stereo had been so I could still see the screen in the sunlight.

The MX5 Cup Final round was at Easter Creek on the GP circuit. I had not dríven this circuit but had done parts of it on the South circuit in the NC and the North circuit in my NB. This created a little bit of nerves for the first practice session.
I took my time finding my rhythm in the NC and this new circuit but the qualifying was stopped after only 4 laps. I managed a 1:55.37.
This gave me a starting grid of 11/16.

Race 1 came round quickly.
The first start, first standing start done in any format was a little exciting.
The start went well but I soon realised that the power of my MX5 was not high in the company I was keeping but the car is well balanced and has plenty of grip. But a good result for my first race improving to 9th place and 1:53.7 PB.

Race 2 had me starting 9th.
I tried to be a little more aggressive on the start but stuffed up the shift from 2nd to 3rd and got 5th. A quick re shift and was back into it but it was too late. I was swamped. This meant I needed to push hard. A bit of work had me catching up and managed to finish 7th with a 1:52.02 PB.

Race 3 was a starting grid of 7th.
A little better start this race but I was behind Paul Nudd as he had benefited on the grid from a retirement in front of his grid location. I had to push hard lap 1 to find an opportunity. I Greg Tasker with his more powerful car driving up the inside of me to turn 6 but managed to hold him out. I had to hang off the apex and try not to loose Paul round Corporate hill and turn 8 I had an opportunity to get up the inside of Paul. He almost got back past me down the straight to turn 9 but I held out. Now just to keep my eyes forward and managed to finish 6th with a best lap of 1:52.67.

I had lots of fun at this event and will be back for more racing next year.

Custardtart · Postby **Custardtart** » Tue Oct 23, 2018 3:39 pm

looks good fun. Are they all supposed to be stock power wise? You were getting much better corner exit but losing out on the straights big time?

Snowmotion · Postby **Snowmotion** » Tue Oct 23, 2018 3:44 pm

Custardtart wrote:looks good fun. Are they all supposed to be stock power wise? You were getting much better corner exit but losing out on the straights big time?

MX5 Cup is pretty much is a MX5 vin and a mazda motor. Pretty open after that but classes are based on lap time.
The red car in the video has 140kw and the blue car has around 170kw at the wheels. Mine is only around 104kw at wheels.
Straight line is an issue but the balance is great.
Need to find more things to cut off

Snowmotion · Postby **Snowmotion** » Wed Oct 24, 2018 11:05 pm

I noticed at Eastern Creek that I had a small amount of binding in the front brakes so I thought it was time to rebuild the front brakes.
If I was going to do this I decided that I might as well do some work on the hubs and the brake cooling.
Having purchased this car as a wreck there are some question marks on all the maintenance. They are not big doubts as the service manual was with the car and it had been serviced by Mazda by the book its whole life so I am confident it was reasonably well maintained.

All the research I did suggested that the RX8 hubs were a straight swap but a little stronger. Definitely not cheaper.
With a bit of help from a good friend RX8 hubs were secured. Now to remove the ones off the car. This is not an easy job as over time a bit of rust has developed around the hub that kept it very firmly in place. Some alternate bolts and a mallet managed to move it eventually.
My aim was to improve the front brake ducting from the driving light locations. I thought about building a whole new dust shield with cooling duct but as it need to sit between the hub and the Spindle knuckle I decided it was better to work with the factory dust shield. A bit of thought and I found a way to attach a cooling duct to the standard brake shield.

With all this sorted it was time to connect the cooling hoses and I took this opportunity to improve the connectors behind the driving light housing. This should help keep the brakes cool.

Time to do a bit weight saving and aero improvement.

Snowmotion · Postby **Snowmotion** » Wed Apr 17, 2019 10:59 am

I have been a bit slack and not posted any updates on this build lately.

I have been working on improving the general fitment of things like exhaust and under bonnet items. I will take some picks this weekend.

But got out for my 2nd MX5 Cup event on Saturday at SMP North. A challenging race with Group N cars in our same event and they are not easy to get past. Below is the Final race of the day that was shortened from 20 minutes to 15 minutes due to an incident in the Clubmen race.
Was a good race but a few mistakes in my driving.

Custardtart · Postby **Custardtart** » Wed Apr 17, 2019 3:39 pm

Looked but man you need more power

another 10kw would see you mixing it with the front cars which given their power is definitely a credit to your speed! :beer:

Snowmotion · Postby **Snowmotion** » Wed Apr 17, 2019 3:42 pm

Custardtart wrote:Looked but man you need more power another 10kw would see you mixing it with the front cars which given their power is definitely a credit to your speed!

A plan is coming together... a bit of work at the front end and a try to reduce drag.
With the Aero I put on the car I have limited my straight line speed but it pays back in the corners.

Snowmotion · Postby **Snowmotion** » Sat Jun 01, 2019 9:43 pm

Having watched the first round of the new TCR series I could not help note that all the cars had a major bumper cut and an exhaust that exist's high and straight out the center of the rear of the car. Seems there is a bit of logic in this design to reduce drag. This is something I need.
So a plan was hatched to make a straight back rear muffler. With a bit of searching I found all the necessary parts. Perforance exhausts in VIC were well priced and quick to ship.
With part in hand I went to work this afternoon making my first exhaust. I basically cam to plan but that said I may rework the mounts.
A little bit of additional welding is required to seal some joints but with some high temp paint it will all be done.

Also a little video of the note...
[youtube]https://youtu.be/vYZ-F16N5pE[/youtube]

Snowmotion · Postby **Snowmotion** » Sun Jun 02, 2019 8:55 pm

Finished off all the last details today with a paint and mounted.
Very happy with the result.

Custardtart · Postby **Custardtart** » Sun Jun 02, 2019 9:13 pm

Looks good and sounds good too!

Snowmotion · Postby **Snowmotion** » Wed Jun 19, 2019 11:00 pm

After the last round of the MX5 Cup I looked at my tire wear and could see that I needed a bit more negative camber at the rear and I the limitation to this was the amount of negative camber that could be put in the front. So I purchased the SuperPro upper A arm offset bush set.
I installed this my self and whilst not particularly difficult I recommend having all the the right tools to do the job. These tools include, Ball joint press kit, a good vice, Ball joint remover. You may be able to get the job done without some of these but when it gets difficult these tools make the difference. So once the swearing was over and it was all installed I had a wheel alignment done and had about -4 degrees of negative camber in the front, about -3.2 degrees in the rear and a bit more aggressive turn in.
This is a great set up for the dry but round 4 of the MX5 Cup was not dry. A wet track at eastern creek following a the Power cruise the day before and the track was the slipperiest I have dríven.
This is the video of qualifying, mistakes and all.

I messed up the recording of the first 2 races but got the final one right where we had a drying track and could push a bit. Set up was still for a wet track so not ideal but lots more fun than the morning.

Thanks to all the other competitors for the good fun racing.
For me it was my most successful day with a class win and 2nd on points for the day. That is not something I thought I would say after the qualifying session.

Custardtart · Postby **Custardtart** » Thu Jul 18, 2019 10:54 am

That’s a bucket load of camber. I’ve maxed out on standard suspension arms at around 2.5.
Is the extra camber noticeable? I’d imagine it would if you’re running slicks or twin grooves?
Live the video, makes me want to get back on track quickly but my next outing isn’t for another month.
Any idea when the new engine will be ready?

Snowmotion · Postby **Snowmotion** » Thu Jul 18, 2019 11:02 am

The Camber is noticeable but given this car is not street dríven car the wear should end up pretty even.
The offset bushes are only $70 off ebay so not a bad upgrade to give more options in set up.
I was not really able to work out the full benefit yet as the track was so wet but it did feel better once the track had a dry line.
I have 2 tire choices, Yokahama A050 or Khumo V710 (twin grove)
Next outing is Wakefield park later in August as too much work this month.

The new engine is sadly sitting in a corner of my panel beaters workshop and not even looked at yet.
I think it will get finalise in October - December when I am not racing.
I will probably also get Daniel to finish the full roll cage then as well.