Firstly, apologies there are no pictures for this track outing. It was on a weekday and a solo effort by myself.
I’ve also shared a post on Facebook to the Live to Dai page.
So we left off with the last track day at Mallala with a 1:36.9 as the fastest time.
Since then has been added:
- Header back exhaust, 2" from BRAVE Japan (headers were already done and are SuperCircuit from Malaysia)
- D-Sport Slotted Rotors (stock GTvi size)
- Ultra Racing Rear Sway Bar
- Rear Torsion bar, front control arm and front sway bar-to-control arm mount bushing from Siberian Bushing
- Copen 5.545 Lower Drive from Compact Motorsport (and Daihatsu)
- 1.5 LSD from D-Sport
- New Gates drive belt and Lightweight crank pulley from Arospeed
The theory behind most of these should be straight forward and documented throughout the site. At Mallala specifically, due to the long gearing of the sirion, all I originally needed was 2nd and 3rd. The lower Final drive has brought 4th in to play on the track, with the acceleration out of 2nd quite astonishing for a small engine (aided by LSD too). I had concerns that this FD was toooo low - but at the end of the longest straight (realistically a kink) I was still in the top of 4th, so didn’t have to make a choice about a short upshift to 5th. Although through the esses I’m not sold on the quickest way through / which gear etc, something for next time.
Downside on the street (aka the drive to/from the track) is that at 110km/h the engine sits just above 4k rpm…so cruising at 90km/h was the ideal mix of keeping revs lowish, noise to a minimum and not angering the other road users.
Speaking of the LSD - given the modest power the cars have, I was surprised on the first track day that I was easily spinning up the inside front tyre. This could also be a factor of not enough wheel droop on the coilovers and/or too stiff a front spring rate. In any case, the LSD certainly solved it, with no wheel spin at all and the ability to pull the car through the corners. I also believe that the locking on decel helped braking.
Speaking of brakes - since they’re stock sized and the recommendation is to go to copen-sized at a minimum the first track day had them running out of puff early. The breaking immediately seemed better, which I don’t think was due to the rotors but the LSD. Though with Mallala being particularly harsh on brakes, the pedal was exceedingly long towards the end of the day.
The Exhaust, pulley, bushings I believe just added to supporting mods - extracting a bit of power, allowing it to rev freely and to feel as solid on the track as possible.
So, my previous best was 1:36.9 and the ‘challenge’ was to beat my friends Proton GTi whose time was 1:34.2 - so I had a bit of ground to make up. Well my actual best time of the day was 1:34.1 just surpassing the GTi. This was also a very consistent time, reaching low 1:34’s on numerous laps. However a bigger story is my theoretical best time pieced together from RaceChrono’s software. Which was a 1:32.9 which is significantly better again than the lap I could do. Having looked at the data RaceChrono does provide - in one sector alone on one lap I was 0.4s quicker. I do feel the area to improve on is the braking - not that the current brakes wouldn’t enable me to get to that lower figure - the variability in the brakes with such a large deadzone prior to braking I feel is where I can’t be consistent each time.
So where to from here?
- purchased a couple of extra fog lights, with the intent to turn them into brake ducts. If anyone is curious, the ‘hole’ at the back of the foglights is 2 1/8" which is the same size as the throttle body, so left over piping / silicone joins can be put to use.
- purchased a ‘chrome’ trim of the passenger side to fashion into an air intake.
- A Fullriver HC20 battery will be mounted under the passenger seat.
- The fusebox has been rotated back 90deg to free up a space for
- Air intake putting a pod filter in the factory battery location, fed air from the front of the car (can’t be any worse than the ‘engine cover intake’), engine bay side ideally blocked by some panel.
- Exploring lighter front rims, with stickier tyres - waiting for a pair to pop up locally or the AUD:Yen to get better.
- Braking…either the Copen upgrade or the Compact Motorsport large brake upgrade.
- Stiffer Rear Springs
Prior to the trackday I did the usual maintenance: plugs, oils etc.
Interestingly, it seemed plug #3 (Counting from Left) was the ‘most oiled’ and likely the cause of the oil burn at high rpm…In any case at the track a large amount of oil was being burnt and therefore needed a few 100mls between sessions. But the 176k kms engine is holding together, I doubt it could be significantly down on power/compression and still create times to challenge its peers.
Next time out will be “The Bend” motorsport track in SA on the 18th August. This is a much larger track to challenge the Sirion.
***If anyone wants to compare the Racechrono data it can be found here: http://www.hyperdrive3d.com.au/pastevents/OtherData/index.php