Splitter’s 2nd NC – “Very Green” (2024)

Splitter

Join Date: Jun 2015

Location: Perth - Australia

Posts: 52

13th February 2020 – Part 1
Wow, where have the past 5 months gone?! I’ve been too busy out racing I guess to have time to post about the events. Poor form. Strap yourselves in, it’s going to be a long update. So long, that the forum insists I make it two posts

‘Spirited Green’ – I like it. It’s certainly a fabulous colour for a race car.

Due to the length of time since the last update, I have 6 events to cover with this one, so I will attempt to keep them brief, only covering what I think are the interesting parts of said events and continuing with the story of driver and car development.

TL;DR: Car is awesome; I suck at drag racing!

Yes, you heard that right, the green machine made its way to the dragstrip. There was a group discount for ½ price laps with one of the local MX-5 Facebook groups, so with nothing better to do on a Wednesday night, I decided to head along. I believe there were about 30 MX-5’s turn up on the night. The event coordinators had us in the regular 4-cyl lane, but we well outnumbered everyone else and it was almost just an MX-5 lane for the night. We were running the full 1320ft quarter mile, not some of the 1000ft “1/4 mile” tracks like in other parts of the world.

The night went fairly poorly for me. So well I didn’t keep my time slips and there will be no shared videos…. The car is not a drag car so I had trouble getting off the line with any modicum of decency. I fiddled a little with tyre pressure but mostly tried to just drive through it. 1.8s was my best 60ft time. Best time for the night was a 15.1 but that was with a 2.0 60ft. The car has a 14.x in it, but with poor launch and struggling to engage the 2-3 shift, I ran out of patience both in myself and the car and left the night early after about 6 runs.

That 2-3 shift is something that I have been struggling with since purchasing the car, and will be covered later in this update.

Not 36 hours after the drag racing event a spot opened up to enter a casual motorkhana / auto test / autocross with some fellow MX5 club members. I had conflicting meetings at work so I couldn’t attend, but when 1hr private track hire is $30ea for 6 drivers, you find ways to utilise that, and my dad stuck his hand up to attend.

If you haven’t seen the YouTube channel then now’s a good time to point out that my father and I have been competing in club level motorsport for ~15 years now, starting in our first car a 1977 Datsun 260z which spawned Dadson Racing in 2004. The Datsun hasn’t seen much track time in the past 10 years, so to be able to get my dad some laps in the new MX-5 at an event like this was a no-brainer.

I spent Thursday night getting the car ready for him and on Friday when he came to pick the car up my instructions were simple:
-Drop the tyre pressure to 28psi before the first event
-Have Fun

Unfortunately my Dad is very bad at following instructions so the tyre pressure didn’t get dropped from the 35 I set them at for the drive to the track. He managed something like 12 autocross runs in the 1hr he had, with the cars cycling continuously over the hour timeslot they had. Needless to say they aren’t wearing evenly any longer.

Otherwise, all went well and much fun was had.

The first week of November proved to be a busy week, with Sunday playing host to the next round of the MX-5 Club 2019 championship. This event was a repeat of the first event I did in the car, an autotest / autocross style event at the infield of the local racetrack.

Nothing much to report from the event, things went smoothly and I managed to keep it clean and off the cones all night, which put me in 1st outright for the night. Smiles all round.

https://youtu.be/FSTKJaitFmU

2 weeks later, and still in November, the MX-5 club held the next round of the annual championship, this being run at the hillclimb/sprint circuit located off the back hill of the local racetrack. It’s a fun circuit and the course included 3 ‘loops’ to put some extra length in the course. This event was a repeat of the event I last reported about in my last post and having the practice event under my belt certainly helped my performance. I was able to drop my lap time by over 2s from the test day but unfortunately my consistency let me down and a cone hit (2s penalty) on my last run cost me the event win, taking 2nd with a margin of 0.2s.

This event came up directly after my last forum post and I took the advice to drop tyre pressure, and boy was it good! Keeping a consistent 29.5psi across all sessions felt much faster than I had been going before.

I logically understand how the MX-5 club events are structured: With only 1 drop run for each event and positions being awarded on cumulative of your “n-1” times, you need to be consistent more than anything else to place well. Unfortunately once I put the helmet on I push hard looking for every 10th of a second, and having ‘burnt’ my drop time with a sighting lap earlier in the day, my cone penalty lap was included in my cumulative time and I gifted our friendly LS V8 NB the win for the day. Maybe one day I’ll learn to keep it clean. Maybe not too…

I was leading with such an ‘insurmountable’ gap to 2nd I also took the opportunity to start playing with hand-brake (e-brake) turns on the hairpin. I didn’t execute very well, but the data logs showed me it was still 0.3s faster than my fastest drive around the hairpin. I will continue to develop this skill as it’s certainly going to be important

https://youtu.be/zLFCcjf-nIA

The final MX-5 Club event for the year was held on one ridiculously hot summer day in December. With little shade and roaring sun it made the 40C (104F) feel extraordinarily long.
This whole event was marred with driver mistakes, most likely due to the hot weather, with an unusually high number of wrong directions, including for yours truly. My day was not impressive, but better than our friend in the LS NB who as first car out on the first course, hit a tree root and split his oil filter, drowning half the track in oil before realising the situation and pulling off track. With the start delayed while that was cleaned up the total number of runs were dropped which meant that top run for each of the 2 courses would count. That worked out well for me as I had a lot of trouble keeping things together and putting in clean runs, but I only needed the two that I managed to take top spot for the day.

When I was gearing up for my last run I completely lost the clutch while the car was cooling between runs! I think I’ve mentioned already in this update that the car is well overdue for a birthday

https://youtu.be/MkjdBmebRBo

That concluded the MX-5 Club activities for 2019. The Western Australian MX-5 club runs their championship as a 10 round, 5-venue duplicate, with the best result for each of your 5 unique events counting towards end-of-year points. I joined 1 event before the mid-year point in the cycle which meant that essentially all my events counted toward end-of-year honours with no drop rounds. Despite the personal challenge of adapting to the scoring system with its intense focus on consistency, an upheld penalty for a rogue cone hit at the point-to-point round, and the technical challenge of joining the ‘prepared’ class in a pre-built car that I’d never driven, I finished equal second in class for the season. First place was uncatchable and went to a highly prepared, caged and striped NB piloted by a highly proficient and experienced long standing club member, who just so happens to have acquired an NC… Bring on the 2020 series

After the dead clutch incident at the last MX-5 Club round I finally got car maintenance high enough up the honey-doo list to get some work done. New fluids all around for Engine, Diff, Gearbox, Brakes and Clutch. This was well needed, and the results have been remarkable: The diff is far less aggressive at low speeds and the 2-3 shift troubles that have been plaguing me since I bought the car are gone. As they should be, because the gearbox bushing upgrades have already been completed.

I also had some time to do a decent once-over of the whole car and have nothing to report other than finding that leaking exhaust was a slightly loose slip joint, so the tin-can noise is now soothed dramatically.

All wheels finally came off and I had a good look at wear patterns. I have driven over 1,000km street miles just to and from events with no tyre rotation yet, and there is quite a severe toe wear on the fronts. The inner-outer edge of the fronts are also wearing quite a lot compared to the rest of the tyre. Terrible description, I know, but if the tyre was broken in to 5 segments from outside to inside, it would be segment 2 – 20%-40% of the tread width is wearing far more than the rest of the tyre which appears to otherwise be wearing very well. I wonder how much this has to do with the over inflation they suffered at the skid pan day my father did, plus also me not dropping pressure enough over the first few events. The tyre pyrometer is telling me temperatures are good across the tyre, and the balance of the car is good so I’m loathe to go changing camber just yet, so hopefully that wear pattern doesn’t continue.

The Nankang AR-1 are not a directional tyre event though they have a non-symmetrical tyre pattern, instead they are stamped ‘inside’ and ‘outside’ so I rotated rear-left to front-right, etc, which I think might be a bad decision and I should just go front to rear, but the events have predominantly been clockwise and so is the local track, so going left to right seemed like a good idea and I didn’t get an opportunity to have the tyres rotated on the rims.

While the car was off the ground I also got around to installing a proper 6-point harness. The car came with a SPARCO 5-point unit that didn’t have the crotch belt installed and also looks far to much like the fake china units for my liking, so I decided to take the opportunity to remove that from the car and temporarily install a 6-point belt that I took out of the Datsun.

I have also stepped up the toy game with the purchase of a trailer, so the green machine is now officially a trailer queen! To be honest, the hot day and cold night transits to/from events without even a fan was starting to get to me. I’m clearly getting old, but my SUV is so much more comfortable to drive on the road long distances!

The schedule for the 2020 MX-5 Club season have been a long time in negotiation, so when I found out about an under-subscribed weeknight event at the local track I jumped. The group are just starting up, but for a reasonable entry fee of $160 with dorian timing included, not to mention 45 timed laps within 4 hours, it was a great opportunity to get some decent seat time in the little car. I logged more competition time in those 4 hours than I have in the preceding 8 months that I have owned the car, insanity.

There were 2 groups of 4-6 cars each, with myself and 2 fellow MX-5’s in group A. By the time we had done our session and got back to the pits, there was time for a drink of water before having to line up in pitlane again. It was another stinking hot day and by 11pm temperatures were still up near 30C (86F) and the car ran flawlessly all night. Brakes got stinky, but no long pedal, no soft clutch, no engine temps. She’s a ripper people!

Bu the end of the night I was getting very comfortable with the car, the tyres, and started playing with setup. I was running 29.5psi hot by the end of the night, dropping 0.5psi each run and still getting faster, so I am going to keep dropping pressures as mentioned above by another poster. I am still struggling with late corner understeer. Once the diff engages on power, the car just wants to push something fierce. Turn-in is fabulous, trail braking is super easy and overall it’s very confidence inspiring and easy to push hard, it just understeers late corner. I also way over-brake going in to the big braking zones. My mind is so wired to faster, more powerful cars, that I haven’t adjusted to the fact that you basically don’t have to brake in this thing! It’s mind-bendingly fast through the turns, even if it does leave a little to be desired on the straights.

To settle some of the understeer, I started playing with the knobs on the shocks, for my first time ever in any car! They were set at 15 of 30 clicks, so I moved them to 10 clicks from full hard for my last run of the night. Good improvement, and I have made another 5 click adjustment so I don’t forget before the next round.

https://youtu.be/nMCFdgxo1zs

I couldn’t wipe the smile off my face all night. I am sure I have demolished the front left tyre by over driving the car as I learn it, and rapidly develop my own driving skills. Did I mention it’s a confidence inspiring car to drive? Because it is!

This group run on the first Wednesday of every month, so I have already started working with the wife for permission for March. Car needs some attention, as a rattle in the steering that I had some help identifying as a sloppy rack end on the left wheel means they need replacing, which means wheel alignment, which I do myself, which means a lot of time required in the next few weeks. Fingers crossed!