Winton Shenanigans
Take my word for it that a lot has changed on this thing, both as a part of fixing things that have broken, as well as upgrades. I have been incredibly lucky in that the industry I am working in while studying has stayed open (in fact got even more busy) throughout COVID, so time has been an incredibly valuable resource all of a sudden, and unfortunately that means I haven’t been able to update this as much as I would have like to (read: at all).
I feel it’s worth the time getting this out in writing though; both for the people that are stupid enough to take a Lib on track, as well as so I don’t forget what I have learnt! Plus I have always wanted to be able to do a Turbo Lag-style track day write up (although probably more ramble-y ).
Between the last track day and this one a lot has changed on the car. In no particular order I am now running a TY856UB1KA from a 2009 JDM WRX STi, with a helical limited slip front different and DCCD, as well as a custom-made 42mm triple core radiator, a 10 row plate-and-fin style air-oil cooler and 2.25 turn (13.1) lock-to-lock steering rack (34110FE550 internals). I modified my adjustable upper rear camber arms to try and get a little more rear camber, and a brake master cylinder upgrade, Motul RBF660, Winmax W7’s, Nangkang AR1’s and Kein engine mounts joined the party as well.
The day started off pretty much perfect. No rain for the last few days, and another track day the previous day helps get rid of any moisture that seeped through the track. The first session started at an EZ30-friendly 20c, with minimal breeze. After having not been able to push the car hard for the last 6 months or so thanks to lockdowns, I immediately realised how out of practice I was, and this was clear with other drivers too, with traffic and general track etiquette being pretty poor.
This didn’t stop the car from feeling absolutely amazing on the first few laps as I got re-acquainted with it! Temps stayed steady around 90c on coolant, and oil barely touched 115c. The steering felt nice and solid, and fresh brake fluid and the 1 1/16” BMC meant the brakes were rock solid. The AR1’s were incredibly communicative through the quick rack, and I immediately remembered why I made these sacrifices to daily-driveability.
However, the first hot lap I was getting a bad sense of deja-vu, with the brake pedal dropping almost completely to the floor. Getting back to the carport the problem was obvious- my heavily used W7’s were no more, and the thin remaining pad material must have transferred too much heat into the fluid, cooking it.
A change back to my street pads- I am currently trying Forza FP3’s- as well as a quick brake fluid flush and the pedal was back up to it’s normal firm feel.
I managed to do a 1:45.275, which considering I haven’t been able to drive the car properly in a long time I am pretty happy with. Watching it back there is still a lot I can do to improve, but its a good second faster than my previous PB and I am happy with that. Plus the car drove home!
https://www.youtube.com/watch?v=LYZGplYGryw&t=6s
Now for my learnings and observations.
The short ratio saw me use much more fuel than I did previously on the drive there and back- settling in a full 1.2l/100km higher than on the stock long ratio 6mt! NVH at 110kmh on the Kein mounts is definitely worse too now that its sitting above 3k rpm at this speed. However, it does mean the 4-5 shift is actually worth it now on the main straight, and I picked up almost 10km/h through this section! Admittedly some of this is the higher cornering speed, but before the swap I would have to shift at the 80m marker before turn 1, or bang it off the limiter for a second or so, both of which ended up taking the same amount of time. I now hit redline at about the 100m marker, and the extra distance means I get meaningful acceleration in 5th!
DCCD on track is amazing- you get the impression this is exactly what it was designed for. There is still definitely some tuning I can still do- I think its locking too much under braking- but the mid-corner grip is something to experience. It is incredibly confidence inspiring and I am 100% certain there is a lot more time to be made up. On some corners it allows you to get back onto the throttle before the apex, and even though you are turning hard you can feel as it works out how best to apply the power to get you around the corner.
You do obviously have to be driving it in the appropriate manner though. It is interesting in that you can got through a corner too fast off-throttle and the car starts to slide, but you can get another good 10-15km/h (and probably more) just by ensuring you are on-throttle throughout the corner, without a hint of under or oversteer.
This feeling was let down quite significantly by my very worn out rear differential. Supposedly this is a viscous LSD, however mine has over 250k kms on it and is definitely acting like an open diff. I thought this was going to fail so much that I actually brought a spare H6 spec B rear differential assembly with me to the track; thankfully I didn’t have to change it out as I have big plans for it!
Cooling system upgrades are 100% required for any H6 on track. I have no idea how people get away without upgrading their cooling systems on turbo EZ30’s on track or even through the hills- unless they just aren’t pushing them that hard. I got Race Radiators in Dandenong to make me a custom, full alloy 42mm triple-core radiator, and I am running 15% glycol, 1 full bottle of Redline Water Wetter and the rest distilled water, for a total of about 8 litres, and in 28c ambient I was still sitting around 98c coolant and 126c oil by the end of the session.
However, I was able to do continuous hot laps (at least until brake fade) without the coolant or oil temperature becoming a problem. Previous to fitting this radiator I could barely get one hot lap before coolant was at the 104c where the gauge moves, and well beyond my avoid-if-at-all-possible 100c coolant temp alarm. This is definitely a good thing, and obviously through the hills ect I have absolutely zero cooling issues now.
The oil cooler also helps tremendously. I never had huge issues with oil temp on track; hitting a max of 142c in 35c ambient on previous track days, but as I still have the factory oil cooler/warmer this places a huge load on the coolant system that I wanted to reduce. Dropping 16c of oil temp with only a 7c difference in ambient is awesome, especially for such a small oil cooler.
Worn-out W7’s suck, but Forza’s FP3’s blew me away! For what is ultimately a street-biased performance pad they held up amazingly well, and I was easily able to get 3 hot laps out of them before the pedal started to loose effectiveness. I have been daily-driving on these for the last 10 months or so, and they definitely have better initial bite, and hold up on track better than Intima SR’s.
Where they blew me away was how well they have recovered after the track day. On the SR’s I would have to sand off well over 2mm of pad material, and then re-bed them in, and they still were never as good as they were before the track day. The FP3’s, after a couple of hard brakes to take off the surface glaze, feel like they are back up to 100% of what they were before the track day. Highly recommended, even over the conventional logic that is the Intima SR’s.
The quick rack is a nice-to-have on track, but as the stock H6 Spec B rack is 2.7 turns lock-to-lock, the 2.25 of my new one is not a huge upgrade. Fitting this rack was a massive PITA, and deserves its own thread tbh, but long story short a successful rack internals swap meant I no longer had a leaky, worn out, loose-inner-tie-rod steering rack!
My hand-work is incredibly sloppy in the video- in fact it was for the whole day. I put this down to tiredness and a lack of practice, but it should now be possible to completely a whole lap without having to reposition my hands, which is definitely a good thing. The increased steering weight and feedback is also appreciated when the going gets twisty; it makes it very easy to feel what the front wheels are doing.
Finally, although they are quite harsh and introduce much NVH into the cabin, Kein’s EZ30 engine mounts feel fantastic on track! My old mounts were completely ruined, and you could feel almost a pendulum effect through corners as the engine and transmission movement was slightly lagging the chassis. The car feels much stiffer, helping everything from turn-in to surface feedback. These are quite harsh though even on the naturally balance EZ30, and not something I would consider if you are not in a position to make the most of them through some twisty corners at the very least. I was considering swapping them back to OEM, but they have been slowly softening over the past few weeks and are now at a point where I can put up with them day-to-day, especially as I now know how good they are when you get to some corners.
Broken Parts
Amazingly I came away from this track day with only two minor failures, both related, if you don’t count me running the W7’s when they were clearly already dead. Both of these related to the new steering rack.
I already knew the quicker rack was going to introduce more resistance to the power steering system, and thus increase the temperature of the fluid. What I wasn’t expecting was literally boiling the fluid in the first session! I was not particularly fast in this session, and experiencing brake issues I backed off early into it. By the time I got back to the carport, however, the fluid was still at 97c and, although it was less than a week old, had already turned a dark black colour, and definitely smelt burnt.
I also noticed after this session the steering was noticeably heavier and slightly more vague-feeling, which I initially attributed to the cooked fluid. I ran out of time to fit a power steering cooler before this track day, but I would now say that it is an essential thing to have if you are running a quick rack on track- or even through longer sections of twisty roads, and one will be fitted before the next track day.
The other failure I noticed driving home, where the car was very hard to keep in a straight line. I didn’t notice this at the start of the day, but as I was exhausted by this point I figured it was just the AR1’s doing AR1 things, in combination with the quick rack. It felt like the car had dynamic toe, where faster steering movements required more movement to get the same turning angle compared to slower steering inputs, and the steering would randomly change its centred location. This was incredibly fatiguing to drive, at a point where I was already exhausted.
After lifting the car up for a post-track inspection like I normally do the problem was immediately noticeable- the brand new Whiteline steering rack mounting bushes had been literally extruded out from their location in the steering rack mounts! The bushes felt extremely soft to the touch, with only minor force required to deform them. Looking back at footage they seemed to have failed on the second lap of the day- which was at 1:56.890 so not fast at all- but at this point the steering wheel was no longer perfectly centred.
As the new rack didn’t come with oem bushes, and my old ones were completely stuffed, I ended up 3D modelling and then 3D printing new steering rack mount bushes from TPU (thermoplastic polyurethane), which seems to be the same or similar material to what the Whiteline bushes are made from, but much much firmer. So far these have been in the car for about 500kms and even though I only replaced the easy-to-replace bottom bushes (the Whiteline bushes are a split bush and the top halves can only be replaced by dropping the rack) they have held up amazingly well!
Overall the car held up amazingly well, and it only makes me annoyed in myself for holding it back. It still feels big and heavy on track, but that’s half the fun especially as I am not racing for a prize or anything like that. I learnt some stuff, and have some minor things to fix, but that’s half the reason I love this as a hobby!