WTF-2J Episode 4: We nearly killed the Supra!! :O Track day testing gone wrong.
If you have been following our "WTF2J" build the past couple of weeks, as part of our "baseline" testing of this car, the "pre modification" phase involved us running the Supra through its paces in both drag and circuit.
We got the drag strip out of the way in the previous episode, so in this episode we take the newly acquired JZA80 to Queensland Raceway to race against the clock.
Unfortunately for us, we (stupidly) did not realise the track layout was destined to be the most gruelling on brakes, and full of high speed straights (three long straights that are each sufficient length to max out our still-enabled JDM 180kph limiter).
This put extreme wear on the brakes, something we had checked but had not considered would be a problem.
The RZ supra is renowned for having some of the largest brakes in its class at the time, however they are not really designed to slow down over and over, lap after lap, when the pads are already near the end of their life.
By the end of the last session, we had completely lost brakes and had to use the hand brake (emergency brake) to prevent us running off the track.
In fact, the brakes were so bad, they caught fire, disintegrated the seals and pistons, and the whole callipers were ruined. As such our day ended with the JZA80 on a tilt-tray tow truck home.
Let this be a lesson to you all, that track preparation needs to be done to suit the actual track layout you are about to hit. Typically in our class we simply have a layout that involves only ONE heavy braking zone. In this instance, with FOUR, we should never have taken the car out on the track with the pads beyond half wear.
Once they got past that 1/4 thickness level, the heat generated was so massive that the pads, rotors and backing plates simply melted away, boiled the fluid, and things could have gone TERRIBLY wrong.
Thankfully we were able to walk away with nothing but a bruised ego.
All that aside, this is just an excuse for more upgrades (big brake kit anyone?! :P).. Stay tuned because after this episode, now that we have all the baseline drag slips, lap times, and dyno power figures - it's time to start bolting on the REAL modifications!!
Next up Suspension and ECU!!
Special thanks to Scotty from Southam Engineering for loaning us his stock brakes, and 999 Automotive for fitting them up :)
Also gig thanks to Qstarz for the lap timing equipment, GT Auto garage preparing the car, and Domestic Mango for creating the video!