OptimumLap Review

Finally had some time to play around with OptimumLap. This is a VERY cool program!

I modelled the track using my GPS data from CSCS #4 last year and modelled my car using some basic estimations and information available from NASIOC and Wikipedia.



I had to make some guesses for values such as frontal area, downforce co-efficient, etc. but after looking at some of the example vehicles they had of passenger cars (M3, Miata, Corvette, R8, 911) I noticed they were all in the same ballpark area. Playing with these values only made thousandths of a difference to the lap time anyway.

Dyno chart I took from a typical Stage 2 chart I found on NASIOC. Since my car was road tuned I never dyno'ed my car. All the Stage 2 charts look similar anyway.

Tire Data, in particular Longitudinal and Lateral Friction, played such a significant role in determining lap time that even changing these by 0.1 had an impact of 2-3 seconds on the overall lap time. I settled for a value of "1" which was somewhere between the street car Civic they modelled (0.9) and the M3/Corvette (1.2).

Final estimated lap time, assuming The Stig as the driver, was 1:20.61. My personal best is 1:22.93. And I still have a lot of work to do with my line, especially through T1. So this does seem to be somewhat realistic.



Digging deeper into the results is where things fall apart a little. Looking at the track speed graph is where I noticed things to be really off. The maximum speed (185 kph) is way faster than actual (161 kph) and the minimum speed (47 kph) is way slower (61 kph). See video for reference:

2012 CSCS #4 - Time Attack - YouTube

Despite these drawbacks, I found the program to be useful in comparing changes made to a single vehicle. For example, adding a VF39 and USDM 6MT would shave off approx. 1 second. And adding just a 6MT without upgrading the turbo would make the car 0.15s slower due to the added weight of the tranny. An extra 100-150whp would net me around 2.5 to 3 seconds in lap time. All assuming I stay with the same tires (since the tire modelling is kinda messed).

Here are the predicted lap times for some hypothetical setups:

• 1:17.55 - Borg Warner EFR 7163, JDM 6MT
• 1:18.02 - Borg Warner EFR 6758, JDM 6MT
• 1:18.26 - Blouch Dom 1.5XT-R, JDM 6MT
• 1:19.13 - Blouch 18G-XT, JDM 6MT
• 1:19.71 - VF39 Stage 2, USDM 6MT
  
• 1:20.61 - Stage 2 (Current Setup)
• 1:20.76 - Stage 2, JDM 6MT

I only spent a few hours playing around with the program. With more accurate real world measurements and some more time playing around with the modelling, I think this could be a very useful tool for anyone looking to maximize their setup. You just need to be aware of what you're playing with so that it's not garbage-in, garbage-out.

In summary, for a free program, Optimum Lap is awesome! 

OptimumLap

Saw an ad for this free software in a racecar engineering magazine today. It not only has the ability to do predict optimal lap times, but can tell you how your lap times will increase or decrease based on a range of variables. For example if you changed your gear ratios from a USDM 5MT to USDM 6MT or JDM 6MT, how would it affect lap times? This software can do that.

It works by modelling your car as a single point on the race track. Given the maximum traction forces of your tires based on real world data, vehicle mass, coefficient of drag/lift, horsepower/torque, gear ratios, etc. it will calculate the maximum apex speed your car can carry and then works backwards to figure out braking zones and top speeds on the straights. It can even model the track for you if you have GPS data (which I do).

Of course there are some limitations such as no elevation changes on the track, difficult to know the true coefficient of drag, etc. but it does seem very neat.

Would love to take some time to play around with it. Maybe over the holidays.

[10/27/2012] HANSON School (DDT)

Event: HANSON International Driving School
Track: Mosport DDT, Skid Pad
Weather Conditions: 6°C, Rain

I just thought I'd stop by for a quick journal update since it's been a while. And before you ask, no there hasn't been any progress on my WRX since last time 

Last Saturday I was given the opportunity to help out the HANSON school as an instructor-in-training. This meant helping out on the skid pad. 



The weather was crap. Great for the students, but not so great for standing outside lol. I tried my best to spend as much time in student cars as possible to stay dry, but I still ended up soaked to the bone.

Even though I'm no pro, I noticed a lot of reoccurring errors from students when I sat in their cars. See if you make these mistakes. I know I've made every single one of them so it was easy for me to recognize since it wasn't too long ago.

Car Control vs. Going Fast
Rain plus skid pad is a very good way to find the limits of the car. There were many RWD cars (lots of FR-S!) and I noticed some of the guys were purposely trying to spin out or power oversteer. I asked them what their goals were, and found out that they wanted to get faster lap times. Drifting around a skid pad is great for car control, but ultimately it won't really help you set faster times. I switched their exercise from doing donuts to treating the skid pad like a big sweeping turn on a track. The new exercise was to imagine the pylon on the skidpad as the apex, and to try and take that corner as fast as possible before spinning out. That way, they could find the cornering limit while going fast in the wet.

Threshold Braking
Many instructors teach students to finish their braking in a straight line before starting to turn in. And for good reason too. On a track, trying to learn trail braking can get you into a lot of trouble. But for the more intermediate students who want to experiment or think they're read for trail braking, the skid pad is the perfect place to start. In addition to the exercise above, I noticed that students were braking WAY too early. They were braking 2-3 car lengths before the marked turn-in gate. If I was driving I would probably be braking 1 car length beyond the marked gate. So I tried to get them to push their comfort zone by braking later and using corner entry to scrub the remainder of the speed. This was easier said than done in the rain though 

Smoothness
Students who braked too early also had a tendency to turn-in too early. They would quickly realize they had more grip than they thought they had, and were moving into the centre of the skid pad too quickly. So, to adjust, they would turn the steering wheel back outward to "get back onto the racing line". Steering input should be one smooth arc, without many big corrections. Having an excess of grip like this means you can be going a lot faster into the corners, even in the rain!

Induced Understeer
The other thing I noticed everyone doing was trying to turn the steering wheel more and more once the car started understeering. This would result in the car vibrating (the tires are beyond its useful slip angle) and then occasionally going from understeer to oversteer once the tires regained grip. Everyone says that their cars understeer (especially on Subaru forums) but the real truth is that any car can understeer if you turn the steering wheel too quickly into a turn (smoothness) and/or point the front wheels past their useful slip angle. It's natural to try and turn the wheel more and more since we want to turn in that direction but the car isn't letting us! But the correct, and somewhat counter-intuitive thing to do, is to back the steering wheel off slightly, and once you feel the grip has regained (through your finger tips while modulating throttle/brake), continue to move the steering wheel back into the turn. The end result is many tiny back and forth corrections while making a turn. If you watch the hands of a race car driver closely you'll see them doing this.

F1 2011 - Mercedes GP - Onboard cameras with Schumacher and Rosberg in the MGP W02 - YouTube Skip to 1:25

Unfortunately I don't have any good photos or videos from this day as it was really rainy and I was too busy with students. But I did manage to get a good rip on the skidpad in my iQ lol. I can't believe how much grip that little car has, even in the rain!

[8/19/2012] CSCS #4 (TMP)

Event: Canadian Sport Compact Series #4
Track: Toronto Motorsports Park, Cayuga
Weather Conditions: 24°C Sunny

I didn't get much sleep due to Dobaru constantly waking me up from howling at stuff all night. I was also still in recovery mode from a hangover on Saturday. So having to wake up at 5AM wasn't the best of starts for me. But I was ready to kick some ass at TMP so that was my motivation!

I got to TMP really early, just before 8:00. Luckily I managed to dodge the police harassment everyone was talking about. During technical inspection my car threw a CEL while idling. Not something you want to see at the start of a track day. I reset my ECU and restarted the car. Stu from Can-Jam came up to me and said "That the startup didn't sound good, Sounds like you may be down on one cylinder." Anyone who has ever reset their ECU knows that the first crank can take a bit longer. So I thought it was normal and carried on with my morning.

Open Lapping

My first session started off behind Mr. Cassidy's RX-7 once again. Although it was in a pure white colour scheme now, and not the space shuttle theme previously :P


Going from DDT to TMP is always a huge change for me. TMP just feels so much harder on the car. On my first session out I had no confidence in the way my car was handling. My underdamped suspension combined with greasy feeling tires lead me into a four wheels off situation at T1 just three laps in. Luckily I didn't take any damage. I pulled into the pits and took a breather to gather myself and refocus.

I spent the rest of open lapping playing around with different lines (shallower, as I learnt on Friday). I also experimented with left foot braking at T4. I was indifferent to it as it had no impact on my lap times so I carried on with regular braking. After T11 I started short shifting into 3rd to carry more speed into the sweeping left hander T12. This change probably had the biggest impact to my lap times as my cornering speeds went up by ~10 kph.

My parents also came to visit me. I took my Dad out and he didn't even last 1 lap :| We spent more time doing up his harness than on the track lol. While we were busy laughing at my dad, xeno_impreza noticed that one of the clamps on my after-MAF hose was completely loose. Thanks man! We thought this would fix the CEL but it didn't. The CEL remained on for the entirety of the day.

At this point both my front and rear brake pads were running really low. I had nothing to gain from going out more as my tire pressures were dialed in and I felt that this was as good as the car was going to get. I didn't get too many hard runs in because of traffic and giving rides but I did manage to set a new personal best of 1:23.96. Finally in the 23's at TMP :)

Richard Nadeau was nice enough to give me a ride in his yellow bugeye beast. This thing is gutted and caged with home made aero. He's riding on HotBits DT2's and powered by an 18G-XTR. I was impressed with the HotBits' ability to soak up bumps. I'm not sure what his spring rates were but his car felt much softer than mine. He was able to drive over the pothole at T2 without upsetting the car and also take a different line through the chicaine which just wouldn't work with my suspension. I believe he was using the tire groove that RedScoobie eluded to in his journal.

Richard ended up doing a 1:20.4 with me in the car. I'm not a very good passenger and this is probably the closest I've ever come to puking in someone's car, lol. I spent the rest of the afternoon trying to recover in time for the time attack. Instructing might not be my thing after all. Richard went on to win Unlimited AWD but unfortunately also managed to break his second 6-speed this year. Ouch!

Time Attack

Sloppy is the best way to describe my run. I even missed a shift in my final hot lap. In all of that chaos I still managed to pull a personal best of 1:22.93, although the official time shown at livetiming.net/cscs showed a 1:23.156.


Unofficial lap times:
Lap 1 - 1:24.31
Lap 2 - 1:22.93
Lap 3 - 1:23.81

Another 1st place finish in a small Street AWD class.

Car Trouble

Towards the end of the day we noticed some smoke coming out of my exhaust on start up. I was hoping the CEL would be something pollution related like the air pump, but the smoke meant it was probably something worse.

I had Monday off so I did some self diagnosis but I wasn't able to come to any conclusions. My car is at Can-Jam right now and I'm prepared for the worst. CSCS #4 marks my 22nd track day and despite 22 being my "lucky" number I guess I was due for some bad luck.

Edit: I just realized I forgot to count 2010 so it's actually more like 27th track day... w/e I'll probably lose count soon lol

[8/17/2012] HANSON School (DDT)

Event: HANSON International Driving School
Track: Mosport DDT (CCW 1 kink), Bowmanville
Weather Conditions: 23°C Sunny

My first time running this track configuration was at CSCS #3 earlier this year. I wasn't happy with my performance there especially with the uphill section of the track. I wanted another chance to practice this layout before the season was over so I called up Peter Hanson at the HANSON driving school and begged him to run the same layout. He agreed to run it for me. I was stoked!

Lots of Subys showed up this time (some missed the photoshoot sorry)!

I was placed in the advanced group and allowed to run without an instructor. But I actually wanted an instructor, as that would defeat the purpose of the school. So I requested one, and Peter said he would come out with me after he took care of some stuff.

In the mean time, I tried my hand out at the skid pad. Last year the only way I could get my car to oversteer was to do the Scandinavian flick. But I only remembered this after my first failed attempt:


I might not be ready for DMCC but hey it's an improvement over last year lol. I only did 4 runs because these tires need to last me two more time attacks!

Now it was time for the second advanced lapping session of the day with Peter as my coach. Here's the vid:


I must've impressed Peter with my driving because after our run he invited me to become an instructor! I was totally honoured and this pretty much made my day :D I told him I would think about it because I know there is a lot of responsibility behind being an instructor and I want to make sure that I'm ready before accepting such a position.

The classroom portion with Derek Hanson was eye opening to say the least. Some of the important tid bits I picked up were:

• Too many people concentrate on the exit of a corner. But the entry of a corner is what separates the good with the best. Shallower entries allow for higher entry speeds.
• Sacrificing linked turns is a misconception. The extra speed gained from taking a shallow entry will make up for the extra exit speed gained by "sacrificing" the first corner for a better exit on the second. You also travel less total distance by not swinging wide. The shallow entry also happens to have the largest radius.

At least that's what my interpretation of his rambling was :p CSCS #4 at TMP on Sunday would be a great place to practice shallower corner entry since some of the turns there are linked.

There was some discussion of the bucking issue I've been having as well. I was trying out a softer rear swaybar setting but it didn't seem to do anything towards the bucking. Although I think the overall amount of tri-podding has been reduced. Here's a GoPro view of the inside rear:


Some of the instructors, including Derek, were watching me on the track. Their comment was that visually they could see the car pitching back and forth. Derek is convinced that it's the center differential "vacillating" as it hunts for the proper torque split. But from my understanding it's locked at 50/50 on the WRX. Although going back to that one ride in Kwan's STI we did hear and feel the wonders of the Auto DCCD working through all the turns I struggled in. Another instructor said I should just buy a Porsche

Peter had previously mentioned improperly matched front and rear springs. That could be it too. And the fact that my dampers are underdamped would cause the car to bounce around as well.

I'm a bit sick of theorizing and chasing my tail with this issue. I could have all the horsepower in the world but if my car still handled like this through corners I wouldn't be happy with it. I think at this point I know I need better dampers so I should just get them first and go from there.

In the end, it was a great day hanging out with friends; some old and some new. And with no real drama other than my EZ-UP tent breaking from the wind lol

Ninja edit: I forgot to post my lap times!

Best lap times per session
Session 1 - 1:02.51
Session 2 - 1:02.54
Session 3 - 1:02.98
Session 4 - 1:02.09
Session 5 - 1:03.03

My best lap time from CSCS #3 was 1:03.31. Amazing how much of a difference improving that one section of the uphill made. Looks like I'll be able to sleep at night again :)

[7/15/2012] CSCS #3 (DDT)

Event: Canadian Sport Compact Series #3
Track: Mosport DDT (CCW 1 kink), Bowmanville
Weather Conditions: 24-30°C cloudy with thunderstorms

My body woke itself up at 5:13AM with a random burst of adrenaline, ahead of my alarm set for 5:45AM. Funny how your subconscious just knows it's going to be an important day. Pre-track day routine was business as usual. Get dressed in light clothing, slap on the sun screen. Eat a big breakfast, forcefully if necessary (hard to eat when anxious sometimes) while watching YouTube and listening to some music. Washroom pit stop (very important!). Pack the cooler with the sandwiches and drinks prepared the night before. Pack the jerry cans, left out on purpose so the car doesn't reek of gasoline. Double check that all my other gear is packed: helmet, driving shoes, GoPro, lap timer, etc. And then head off to Mosport :)

Pit lane was set up around the skid pad because the rectangular paddock was used for the show & shine and vendors.. This is something I wasn't used but it worked out better than I expected. There really wasn't much for me to set up today as I had done everything, including set my initial tire pressures, at home. All I had to do was put up the EZ-UP tent and then kill time until the technical inspection opened up and then driver's meeting.

I got a good jump on the crowd and was one of the first in line for tech. Great start to the day for me and weather seemed to be holding out for now, although forecasts did call for a 40% chance of thunderstorms around 2:00PM and lasting throughout the day. As long as it rained for everyone during the time attack, there was no need to sandbag the competition ;)

Open Lapping
 Racing the 'Bro'
My first session features Andrew Cassidy's RX-7 on a semi-wet track. Although I had a great start to the morning, the same couldn't be said for some others. Vinh, who had snapped his left half-shaft at CSCS #2 in Grand Bend, had snapped the other side on the very first lap of the day. Back-to-back DNS must suck.
BC Racing Civic Disaster!
But that was nothing compared to the terrible incident involving Joe Liu's BC Racing EK9. I'm not exaclty sure how it happened, but you can see from my footage that it was quite a shock to see his car upside down on the front straight. I've seen Joe's car out many times before so it just goes to show how anything can happen at the track despite someone's experience level. I should really consider a half-cage/roll bar if I continue to do time attack in the future.
Struggling with the Uphill
I was having a very difficult time re-learning the uphill portion of the track. I think it's because I've done the CCW 2-kink layout so many times from SRTA that it's become second nature to me. Without the first kink on the uphill, my entry speed is way higher into the uphill S and it was throwing me off my pace all morning. MIBAgentQ had a good tip which was to visualize yourself coming out of T6 in the 2-kink layout. This meant keeping track left over the first part of the S, which is a bit counter-intuitive given the nature of the blind corners. It seemed to work for me. But then I was still confused with the exit of T5. I couldn't figure it out all day, whether or not to late apex or turn-in regularly. Almost everyone I went up against seemed to pull away from me there. I had been watching videos of the CCW 2-kink layout all week in preparation for this event so I felt a bit frustrated that I still couldn't figure it out. Sti_04 you're in this video!
To add to my list of problems was my left front making the clicking noises again and the bucking/chugging feeling from lack of damping. Regarding the clicking noises, I wasn't sure whether or not I should have kept pushing and trying to shave tenths, or to save the car for the time attack and collect points. But after some reassurance from Can-Jam that my car wouldn't explode, I decided to keep practising. Every time I run DDT it's a painful reminder of the poor decision I made to buy cheap coilovers 2 years ago. A good suspension setup is crucial to getting good times at DDT.

Mario Kart Shenanigans
My final run of the day featured some interesting action following two Hondas. VTEC kicks in quite frequently in this video. Windows movie maker is terrible at adding sound effects so you'll just have to imagine the banana boing sound and Luigi going "Ahwowowowow" in your head ;)


Best lap times per session:
Session 1 - 1:03.71
Session 2 - 1:03.31
Session 3 - 1:03.88
Session 4 - 1:03.43

Time Attack

As grumpy old Mac was wrapping up the driver's meeting for the time attack, thunder struck. Some small chuckles broke out amongst the drivers but I know everyone was really thinking "FML"

It started to pour as the time attack was just about to get started. Not sure what happened but the first few heats were stalled quite a bit. During this time, the rain was subsiding but the damage had already been done to the track. It's a good thing I decided to just go all out during qualifying and not sandbag. I would've been punished so badly for that haha!

I love racing on a semi-wet track as it really tests your ability to adapt to changing conditions. I also love watching other people tackle the wet tracks too. I'm not a big fan of drifting, but when it's the fastest way around the corner it becomes the most awesome thing in the world. I really enjoyed being a spectator for the first 7 heats of the day. Kpower elicited a crazy reaction from the crowd when he held a crazy powerslide on the uphill section of the track and only to lose it at the very last second. We all thought you had it man! Nice try. Looking forward to the footage on that one lol.

By my turn the rain had completely stopped but the track was still semi-wet. It helped that people were driving on it so some dry patches were starting to show up. But still plenty of standing water, especially on the downhill. The entire back section of the track, especially T5/T6 felt like it was covered in oil. I had a few moments where I thought I was either going straight into the field, or going to end up backwards.

Despite my trouble I guess I was doing relatively well as I was able to catch up to the RX-8 in front of me after only the very first lap. AWD FTW. But it wasn't doing me any favours because of the pace of the car ahead of me. With 3 of the cars in my heat being RWD, I had even volunteered to lead the pack but they stuck with their decision to keep me in 3rd. It was mildly frustrating to say the least. You can see it from my GoPro footage that I had to back it off a LOT. Even after they released the RX-8 in front of me and gave us 2 additional laps, MIBAgentQ had somehow managed to catch up to the last car in the pack and now both of us were blocked lol! SRTA trained us well man!
Official time was 1:06.539, enough to put me in 1st place for Street AWD again. Personally, I wasn't happy with the time because of how blocked I felt during the run. I asked for a re-run but they wouldn't let me go out again because I had already won my class. I would have only held up the event for a selfish reason. While this much was true, leaving time on the table is never a good feeling. Still, a win is a win so I'll take it :D

To do:
- Fix left front clicking noise (most likely driveshaft)
- Get some rest

[6/29/2012] Track Report (TMP)

Event: TCI & TMMC Open Lapping
Track: Toronto Motorsports Park, Cayuga
Weather Conditions: 31°C, Sunny

Here's a real quick track report. A few of my co-workers went lapping today so I took the day off work to join them for moral support.

The track was barren. Maximum number of cars on the track at any given time was three, lol!

Weekday lapping is such a great time to practice. Some un-cut videos of my friends' driving:
An interesting note riding in Lelan's IS300 with an open-diff: Because of the open diff, there was crazy bogging through the corners. I have a similar feeling in my car although not as intense. The 06 WRX has an open front diff if I'm not mistaken. I'm starting to think that maybe it's time I start looking at upgrading my diffs as well. It never ends :|