One of the first things I did after the Hako was run-in, was attend a trackday at my favourite racetrack, Wakefield Park, which is 2hrs south of Sydney. This was in August 2009.
It was really just a shakedown run for the Hako, and while we were all pleased with how she went, in truth I'd got a lot of things wrong. The spring rates were way too soft in the rear, and the front end was undertyred, so my laps were all a mess of squealy understeer. But one thing that did work very well was the freshly minted engine, which provided heaps of brute force out of each corner and down the straights. So while the brakes and handling weren't too pretty, we did come away with a half-decent 1'15.5 laptime. So as far as shakedown runs go, it went pretty well.
Since then of course there's been some pretty constant fiddling with the car, and I've always wanted to come back to Wakefield to see how much better she goes. In terms of mods since that first trackday in 2009, we've doubled the rear spring rate (and there are new GAB adjustable shocks back there too), the skinny Yokohama C-Drive front tyres have been swapped for stickier and wider Falken Azenis hoops, the brakes are shod with Endless NL97 pads and shoes all round, and there's about 30 more horses in the stable.
So when the opportunity arose to attend another Wakefield trackday a few days ago, I jumped at the chance.
Well I won't put you in too much suspense, but the new best laptime is 1'13.95, which was timed on my iPhone by the really rather cool
Harry's Lap Timer app.
It's a GPS-based lap timer which works out your laptimes using GPS waypoints around the circuit using google maps (or something like that...)
I'm not sure how accurate any iPhone can be compared to say a Driftbox or something, but it does have some cool features. There are three ways you can configure the laptime display, but I chose this one, which shows your current laptime, and sector time, compared to a "reference" lap, which in my case was my best previous lap. And it flashes red or green depending on whether you are in front or ahead.
The app also allows you to record a video and overlay some data onto the display too. Unfortunately the camera mount fell off during the 1'13.95 lap, so here's the second-best lap
http://youtu.be/_Lk3uTt1tG4
The day was quite well-attended, so there was a lot of traffic to contend with as you will see.
http://youtu.be/onBStj8JM6c?hd=1
But overall the Hako ran just great. The handling balance is pretty much where I want it, and the heavy understeer problems I had before are now gone. In fact, even in the fast sweepers, you can still push the tail out quite easily with the power, so the balance is great...like night and day compared to before. If you compare these vids to the previous 2009 trackday, I'm using far less steering lock to turn the car into the apex, and once at the apex, I'm actually unwinding lock now as the power feeds in....compared to before when the understeer got even stronger on corner exit. At the end of this run is my fastest lap of the day, and you can see what happens to the camera as I begin the lap!
http://youtu.be/fuyEg_-vsV8?hd=1
The brakes are better, but still fading badly during a 20min session. I guess in a supersprint context, where you only do 3 flying laps at a time, the heat buildup could be managed better, but after about 6 hard laps the pedal starts to get really long. One thing that did stay cool was the temps, and the ducting and upgraded rad seem to be doing their job, and the water temps didn't go over 85 degrees all day.
http://youtu.be/_f5aeB9WHUw?hd=1
But here's a cool feature of the Harry's Lap Timer. You can plot speed-vs-trackposition traces and compare laps against each other. Here's the traces for the traces for the 1'13.95 fastest lap, against the 1'15.10 hot lap above with the data readout on it.
The 1'13.9 is the red line, and as you start from the left, we are hammering down the main straight and you can see that the braking point is the same. Then the line goes downhill as I brake, and the entry speed for the first turn is actually the same too. The exit speed is the same too, and the 2 laps are neck and neck as the Hako speed uphill towards the little esses at the top of the hill.
That's where the time is gained on the faster lap. You can probably tell from the hotlap footage (at 18secs) that I'm not really fully committed through the esses, but in the 1'13 lap I'm not lifting as much and holding much more speed through the esses and then through the 90 degree right hander (at 22secs) at the top of the hill. Going flat(ish) through the esses meant that the right hander was taken in a bit of a mess of understeer, but it's actually the fastest way, and you can see there's a lot of time gained there.
Then the line goes upwards towards the half-way mark again, and this represents the downhill right hand sweeper in the middle of the lap (at 32secs). If anything, the 1'13.9 lap is a bit slower here, and the 1'15.1 lap gets up to a faster speed on the sweeper exit just before braking. I'd put this down to the brakes being fresher at the beginning of the day when I put down that 1'15, when I did the faster lap, it was later in the day when the pedal was a bit long, so I probably backed off earlier.
At the half-way mark on the trace, the line plunges doward again and I hit the brakes heavily for the long slow double-apex left hand hairpin that we call the Bus Stop (at 41secs). As we accelerate out, the lines go upwards and it's line-ball, and that little downward dip is me backing off for the right hand sweeper (at 49secs), and on the red lap, I'm backing off later on entry and keeping my entry speed much higher, so this is the second spot where we gain a lot of time.
Then we go flat out and the traces plunge downward one more time as we brake for the hairpin coming onto the straight (at 1min), and it's line-ball between the 2 laps again. Interestingly, on the red lap the last peak before braking is a square shape...this is because the brakes were getting really long, and I had to give the pedal a couple of pumps before committing to braking, so that's why the speed is constant for a heartbeat or two (and that gives the trace that weird square shape).
It's interesting that a bit more aggression in just 2 corners of the track make such a big difference to the laptime. But I remember from events in my old MX5 that it was the same thing, and that run up the hill and blitzing those esses as fast as you could really made a huge difference, because you were maintaining speed going up the hill. Lift off more than you should and the gradient meant that heaps of speed would bleed off, and that would be reflected in the laptime.
As I said, I really don't know how accurate this is, but as a self-training tool, it's fantastic! Certainly the next time I'm at Wakefield I'll be tracing my laps against the data from the 1'13.9 lap, just to make sure I'm subconciously not being as aggressive and losing time without knowing why.
But I can't complain about how the Hako performed, and if I look back at the Aug 2009 trackday, a 1'13.9 would have put me right in the middle of a pack of Lancer Evolutions and Silvias running motorsport tyres, so Hako isn't going too bad for an old crate. You can probably hear that at a few spots on the track, there is a lot of inside wheelspin, so an LSD will improve things a little, and that should hopefully be sorted in the next couple of months. The other obvious area for improvement is the brakes, and I reckon some sort of 4 piston caliper upgrade up the front will be what the doctor ordered, so I'll start looking into it. You can also hear that the left rear tyre is touching the bodywork on corner exit sometimes, this is because I'd removed some of the packers under the bumpstop when I fitted the stiffer rear springs, I didn't think I needed them but I guess I still do.
But unfortunately, at the end of the day we also had this:
...those water marks are leaking coolant, which means a blown head gasket. Funnily enough, it isn't using any coolant, and drove pretty normally on the way home. It was using a bit of oil though, especially on decel, where you could see some smoke (I presume that's from cylinder vacuum pulling oil into the combustion chambers). But I take heart from the fact that it wasn't overheating, so fingers crossed that the head is fine and not banana-shaped.
So at the moment, the Hako is all apart, and the head will come for the first time since 2009. But...sadly, in taking the car apart I did find something else quite interesting, but fixing it will mean that we won't be able to make the Datsun Nationals at Wakefield Park this weekend.
More of which anon, but I think Hako will be off the road for a little while until this issue is sorted.
