Track Junkies - Castrol Raceway
Let's pick up where we left off! Hop in your imagination machine and set the coordinates for... Canada! It's just like America... but everything kind of smells like maple syrup.
Car Setup and Testing
A few changes were made to the setup of the car after reflecting on the driving and racing experiences of the last year. I had started with the KWs set at full-soft for compression and rebound damping last year but I found the car was hitting the bump-stops while traveling over rough roads, so I changed the compression and rebound to medium.
Additionally, the car was extremely low which also contributed hitting the bump-stops, so I raised the KWs spring collars five turns on the front and rear. This significantly reduced the quantity and severity of the car hitting the bump-stops on the street and added some responsiveness… I guess there is such a thing as too low! Anyway, damper tuning is something I have a lot to learn about but I’d at least like to get to a useful start-state.
Testing of the Race Capture Pro 3 (RCP3) involved setting my neighbourhood loop as a custom track as and driving around it again and again and again… the neighbours sure give you some funny looks when you slowly drive past their house for the tenth time. In any event, the system worked as advertised and was ready to start measuring signals and flipping bits for the track day.
The bushings and subframe inserts provided an immediate improvement in shift quality, especially under load and sharpened up the throttle response a bit. Having a turbo does dampen the throttle response so the improvement wasn’t as dramatic as it was in my old AW11s. There was an increase in noise/vibration in the cabin but not near the same degree as in my AW11s… in fact, the increase wasn’t really noticeable on the street or highway when driving in a normal manner. The worst of the resonance seems to occur around 3500 - 4000rpm.
To confirm that the master cylinder was working correctly and to get the tires and pads ready for the track, I scrubbed/bedded them in on the street. This involved starting with gentle driving to get a bit of warmth into the tires and pads, and then a series of decelerations from a moderate speed (60km/hr down to 20km/hr), followed by a series of aggressive decelerations from higher speeds (100km/hr to 30km/hr). I was not prepared/expecting the level of friction these pads and tires provide once they’ve got some warmth in them and you start to press hard… BANG! It was like hitting a wall! I could finally get the ABS to kick-in in order push the tires to their braking threshold. The new master cylinder provided a firmer, more modern feel to the brake pedal too, which I greatly prefer. It was difficult to get a sense of how the modulation was going to feel at the track as the street isn’t the place for that level of driving or testing, but it gave me hope that the MR2 would finally have the braking it deserved. The pads also proved effective on the street, even when cold. They do make a bit of noise from time to time on the street and an incredible amount of dust but so far they are really impressive… it’s going to be an interesting track day!
And that’s it… the MR2 was ready for battle!
It's not actually that clean - filters, yo!
Did I forget about the driver? Almost! The driver has been getting ready too. I’ve invested in a gaming PC and VR system to do some off-season driver training… it’s a bit weird and frankly nauseating the first couple of times to drive in VR, due to the lack of g-forces my brain was expecting but I quickly adapted to the experience and haven’t had any issues since. It definitely kicks up the realism and immersion compared to using a normal computer screen for racing games. My setup uses the Oculus Rift VR system, a Thrustmaster TX wheel and three pedal system and the Thrustmaster TH8A shifter. I’ve combined that with the GT Omega Pro Racing Cockpit. My racing simulator of choice is Assetto Corsa, due to quality of the simulation, the availability and quantity of additional content and the enthusiastic community.
Track Day - Track Junkies - 21 May 2018
First event of the year! Let’s get out there and make some brake dust… this was a lapping day hosted by Track Junkies at Castrol Raceway in Edmonton. It was a beautiful day with temps around the low 20s C with steady winds and lots of sun. It was well attended with a wide variety of cars and drivers and everyone was friendly and out for a great day on the track!
Track Day Basics
The event was divided into four groups: green for novices and slow cars, yellow for novices/semi-experienced with faster cars and red for experienced drivers with fast cars. The fourth group consisted of the time attack competitors. All sessions required a “point-by” from those being passed with more passing areas available to the more experienced groups. Instructors were provided to the novices and those that requested them. I would be running in the yellow group and as I was novice with the club I would have an instructor. As it turns out, the instructor was the best part of a great day at the track!
In addition to the standard drivers’ meeting that covered the basics of running on the track safely, classroom sessions for the green and yellow groups covered the basics of performance driving and the key points for driving around Castrol. The analysis of Castrol was a very interesting briefing as it revealed the impact different track features and topography can have on car handling and the ideal line through each section.
Go time!
After a 20-minute “reduced speed” warmup/course familiarization session, each group had four 20-minute sessions spaced throughout the day to hit the track. Additionally, there was a 30-minute open track “happy-hour” session at the end open to all drivers. It doesn’t sound like a lot of time on track but it ended up being the perfect amount. Each session was just long enough to get the tires overheated and the driver’s head full of excellent coaching from the instructors. The breaks in-between the sessions were perfect for refuelling, rehydrating, checking the car over and analyzing/absorbing the lessons received.
Warmup session, Miata on my six!
Track Overview
I'm a nerd, you're probably at least a partial nerd, let's nerd out on the local track. Castrol Raceway is a tighter, technical track at 2.7km with 14 turns. Elevation changes are very minor, so the track is essentially flat. Castrol Raceway has graciously made their track engineering drawings available online so I’ve transposed those into a picture. Included is the distances and turn radiuses and slopes.
There were a few important points passed on by the instructors with respect to the track surface and features. These included:
Curbs! We all want to hit the curbs, right? All the pros do it, it looks cool and it sounds even cooler… but, here’s some advice for Castrol: hit some, miss others! Some, such as the inside curb on turn 4, will unsettle the car to a dangerous degree and put you straight into a wall on corner exit. Others, such as the inside curbs on turns 10 and 13, will help you rotate and shorten your line. You need to know which is which and how to use them. Additionally, the backside of curbing can be quite dangerous as the soil can get worn away and it can then hook the inside of your tires and cause a loss of control.
Turn 4 – That’s a wall. See that curb? That’s a launch ramp into the wall.
Turn 13 – Hit that curb! This one will help you rotate and shorten your line.
Crowns. Castrol was paved like a road; it has a crown. This can cause issues in certain areas where you are crossing the track after hitting one apex and heading for a turn-in point on the other side, and make certain maneuvers challenging due to the grip of the car not being what the driver expects.
An example is crossing over the crown from the apex at turn 7 to the turn in on the opposite side of the track at turn 8. You need to be essentially traveling in a straight line after the turn 7 apex as you’re coming over the crown in to the braking zone and turn-in point for turn 8. If you’re still turning as you cross over the crown you’ll find it quite tricky as you’ve transitioned from an on-camber area to an off-camber area which substantially reduces your grip! Being late on your turn-in to turn 5 and missing the apex can have a similar effect as it puts you on or over the crown instead of on the on-camber slope into the turn.
The correct line. You have the wheels straight as you go across the crown and then brake on the other side of it so the car’s grip and balance are consistent. No issues at all and the late apexes ensure you’re carrying a lot of speed and lined up straight for the next corner.
The exciting line. If you take an early apex at turn 7 you’ll potentially be continuing to turn after the apex and can end up going over the crown while still turning, which causes a change in grip and balance. Additionally, you have to go back over it if you’re going for an early apex on turn 8 which means the car’s grip and balance will change again while under braking! I’ve tried this line, simply due to inexperience, on previous lapping days and it is rather unsettling once you get near your traction limit as the back end of the car starts to wiggle and oversteer at a fairly high speed.
On Track – Driving Technique and Feedback
The first session out was my first chance to drive the whole track at speed and for the instructor and myself to get familiar with where my driving skill and track knowledge were at. Each subsequent session built on that foundation as the instructor continued to evaluate and develop my technique and course knowledge. As it turned out, there was an incredible amount of information and feedback provided!
As I’m not an experienced racer, we spent the time covering the basics and correcting my bad habits. For driving technique, we worked on:
Hand Position. The instructor noticed that I tend to have one hand higher on the wheel than the other and that led to me going off the line (and putting a couple wheels off track a few times…). I worked on maintaining a 9 and 3 hand position throughout the day and it improved my ability to sense where the car was going (precision matters!) and put the car where I wanted it. Hands do not need to move from those positions with this car on this track and I expect most tracks will be similar for MR2s (at least those with power steering) due to their faster steering. Requirements for autocross may be different due to the tighter nature of courses.
Looking Ahead. Looking to the apex and then looking through/past the apex. I do it, but it’s more of a mechanical pointing of my head, not an automatic or comfortable motion with my eyes. It did progress through the day.
Heel and Toe. I’ve been doing heel and toe for years, both on the street and track. What I need to work on now is ensuring I’m fully using the brakes while doing so and maintaining consistent brake pressure.
The Line and Precision. While racers are generally familiar with the “perfect” line (wide entry, later apex, etc), the reality of the actual track surface and features, and the capabilities of your car mean your fastest line might be a bit different. As an example, on some of the corners on Castrol, smaller, lighter cars with grip don’t necessarily need to enter a big corner as wide as the “perfect” line dictates. Also, when hitting your braking point and the apex, precision really matters… the closer you are = more room and time to accelerate through the apex and on corner exit. This is how you find those tenths and hundredths of seconds that drop your lap times.
Turn 6 – How not to hit the apex. Precision matters!
Using the Full Track Width. After hitting that apex, the more track width you use on the far side to let the steering unwind, and the more quickly it unwinds, the less speed you’ll be scrubbing off as you reduce your tires’ slip angles. To help this, I need to get a better sense of where the corners of the car are. A lot of the time I would hold too much steering angle for too long after coming out of a corner and a few other times I’d accidentally get a couple wheels off the track. It got better through the day.
Trail Braking. On third session we started to add trail braking. Braking later and then gradually easing off the brakes as steering is added. This allowed me to brake later, in addition to feeling like it made for a more stable, smoother turn-in. This allowed me to brake quite a bit later on turn 3 and it was ideal area to practice it. More work is needed to add this into each corner.
Rolling on the Throttle. Maintaining neutral throttle (10 - 25%) from turn-in/corner entry to approaching the apex, then using throttle to help the car to rotate into and through the apex. Using the throttle to help the car rotate was new to me, as in the past I’ve usually used it to push the car out/understeer and instead ease off the throttle if I wanted to turn in. Still wrapping my head around this one but it’s fun!
Sharp Cornering. In turn 10, the instructor directed me to get very hard on the brakes and then crank the wheel around rapidly. What this did was get the car to stand on its nose, and then quickly bring the unloaded rear tires around. This worked incredibly well and I caught just about everything in my run group in this combination of corners… it really showed the agility of the MR2. Additionally, for turn 10, instead of following a “perfect” line turning in from the outside, we’d actually make a straight line from the late apex at turn 8, go straight through turn 9 and conduct this turn in from the middle of the track for turn 10. When I got it right, this would dramatically shorten the corner and put me on the left side of the track in the ideal spot the turn in for turn 11.
That near cone is the late-late apex out of turn 8. Hit that and you can see it’s almost a straight line through turn 9 to the turn-in for turn 10!
The straight line through turn 9 and the sharp turn into turn 10. Note that the turn-in to turn 10 is from the middle of the track and the apex is right at the end to ensure you’re fully on the left for the turn-in to turn 11.
Racing Technique. I’m comfortable driving in traffic but I do need to maintain better awareness of what’s behind me. The instructor recommended checking my mirrors after every corner as the passing operates on a “point-by” system. The “point-by” system can be frustrating at times as while I was catching some more powerful cars in braking and the corners, when they pointed me by they wouldn’t actually let off the throttle so it I wasn’t able to complete the pass… but if you keep catching them in corners eventually they get it and slow a bit on corner exit to let you pass on the next straight. Overall though, no issues with other drivers. Everyone was courteous on and drove safely.
On Track – Vehicle Performance and Feedback
Handling and Balance. The instructor really liked the handling and balance of the car! I was pretty happy to get feedback like that and it confirmed my own assessment.
Ride Height. The instructor noticed that the car was hitting the front bump-stops under hard braking on corner entry. He recommended increasing the ride height as opposed to increasing spring rate or damping, as those could decrease grip. I’m not opposed to this as this will further improve street-ability too.
Turn 13 - That’s not the line…
End of the Day – Subjective Assessment (Driver Analysis)
Alright! First track day done and the shiny side is still shiny… let’s see where the car is at when comparing its performance against my goals.
Handling. Handling is ideal; responsive, neutral and highly controllable. It’s very predictable and communicates to you, even at the limit. I had a couple moments where the back-end started to step out a bit and by just maintaining throttle with a very small amount of counter-steer it just planted and went. What’s even better is that I knew it was going to step out before it did and that I could do it on purpose! This inspires confidence, which is the complete opposite of my initial racing experience in both AW11s and SW20s which I found twitchy at the limit. At this point I’m totally happy with the handling! Objective achieved!
Ride Quality. Ride quality is better with the additional ride height and stiffened dampers. A little more height and it might even be approaching comfortable?? Make no mistake though, this is a harsher ride than a stock MR2 and is a bit tiring on road trips. While not an issue on the track, the Suspension Techniques anti-roll bars do cause bobbling on surface changes on the street as they’re quite stiff. I will re-evaluate after raising the ride height and having another track day.
Performance. Cornering and braking grip are very good, however I haven’t yet hit the limits on the track in a consistent or deliberate manner. The traction limits are far too high to be exploited in a safe manner on the street. Once everything is warmed up (tires and brakes), brake modulation is good and there’s finally enough pressure in the system to get the ABS to do its job. However, the car now feels underpowered… throttle was pinned during/after hitting the apex and did not appear to be anywhere near the limit for rear tire grip during corner exit. I need more track time to evaluate the performance of the car, as consistently getting the car out onto its traction limit is currently beyond my ability… that said, it’s starting to get tempting to get a bit more power given how much grip it has and how controllable it is. Remember, I'm running a stock gen3 motor with minor bolt ons, OEM boost even.
Ok, let’s break it down a bit and look at the individual effects of all the new bits and pieces on the car:
New Tires. The new tires do provide more grip than the old ones. They heat up quickly too. While they did overheat around the 15-minute mark of each session a bit of gentler driving was enough to bring them back into their operating range and they didn’t get “greasy” in the same way the Falken Azenis did... it was just a gradual and gentle decrease in grip when overheated. Their handling was very consistent and predictable and they communicated well. More track days required to assess wear characteristics.
New Brake Pads and Master Cylinder. Amazing. Totally happy. These did not overheat, and they were very consistent and provided great feel and modulation. They are effective from cold and just get better as they get hotter. I think the only improvement I could make at this point is a master cylinder brace to tighten up the feel a bit and improve modulation. Brake balance seems good at this point.
Those wheels were white…
New Engine Mount Bushings and Subframe Inserts. Excellent upgrade. The shifter felt perfect, which is vastly different than before where under heavy acceleration it could be a challenge/impossible to shift quickly. As mentioned earlier, as it’s a turbo car there isn’t a big change to throttle response as the turbo mutes your throttle inputs.
Increased Ride Height. As much as it pains me to raise a car (higher centre of gravity = bad!), hitting the bump stops on the track and street is not a good thing, especially if it happens mid-corner! There didn’t seem to be any negative effects on handling that I could discern from the increased ride height.
Increase Compression and Rebound Damping. It felts like this contributed to the car being responsive and balanced. It felt like I could out-manoeuvre everything else out there in the tight corners and put the car where I wanted it. I might play with these in the future but it’s difficult for me to subjectively assess this.
New Helmet. Comfy! No issues at all. I may get a tinted visor as driving into the sun sucks!
Best Modifications for SW20s. For those new to MR2s and racing, it’s very easy to get lost when wondering where to start spending your hard earned dollars… if you want to get faster and, more importantly, enjoy the sport and get your money’s worth, here’s where I recommend you start:
Driver Training and Track Time. Getting on track is good. Having an instructor to provide feedback and coaching is vastly better. Practically all of those new to track driving will be coming in with bad habits and undeveloped skills and senses. By having a coach in the cockpit with you, you’ll get immediate coaching and feedback on your technique while also getting a personal guide to the best line and key points of the track. I cannot recommend this highly enough!
Modifications only last the life of the part or the car, whereas driver training lasts for your life…
Suspension Bushings and Wilhelm Raceworks Suspension Geometry Kit. Out of the box, the MR2 is a quick machine with good handling but it does have a bump-steer issue which can make it intimidating and potentially dangerous for a beginner. Once a driver gets burned by swapping ends on the track or street it can be hard to regain confidence in the car and your own ability. By combining the suspension bushings with the Wilhelm Raceworks Suspension Geometry Kit the car’s handling becomes more responsive, you will have a better feel for what the suspension and tires are doing, and the bump-steer issue is eliminated. Additionally, the geometry kit will increase the car’s cornering grip due to improved camber curves. This will allow you to be more comfortable pushing the car to the limit through the corners which will allow you to work on improving your cornering technique and gaining confidence, as opposed to being ready to counter the oversteer caused by the bump-steer issues. Big thanks to Alex Wilhelm for this kit! He’s deserves our support as he’s one of those keeping the MR2 dream alive and makes excellent products for those want to increase the performance of their cars!
(Of course we will link you Alex's kit, spend your Loonies and Toonies HERE)
Packing up and going home!
End of the Day Wrap Up and The Next Step
As a driver, my skills have a long way to go. This first track day this year was just about learning the basics of performance driving and learning a basic line around the track. Next time out, I’ll start to work on a few specific skills and increase my comfort and confidence.
Here’s the plan:
Increase Consistency in Braking and Cornering. I need to start using references for braking zones and using consistent braking pressure. I was purely braking by feel this time, which led to very inconsistent braking. Additionally, I wasn’t using a reference for turn-in which led to trying a lot of different lines through the corners and apexes. Not a bad experience but if I want to get lap times down then I need to be consistent.
Get the Car on the Limit. In a lot of the braking zones and corners I was very rarely at or near the limit in any kind of consistent manner. This is going to take some time to develop a feel for.
As for the car, I’m very happy with the handling and performance for now. I’ll raise the ride height a bit which will, hopefully, put the bump-stop issue to bed. At this point my own driving skills are playing catch-up to what the car is capable of! That said there are still a few things to do to increase the handling and performance (lightening, power, downforce, data gathering)… we’re just getting started!
For the next article we’ll take a detailed look at the track, the line I used and why and, finally, get into the data analysis with some numbers, graphs and vids! Exciting stuff, stay tuned!