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Category: Indoor Karting
Posted by: Mike
At around 135lbs, I'm obviously constantly ragged on when I set fast laps at the local indoor tracks for being able to do it because of my weight advantage to most adults persons of the male gender. I can't say it's not justified.

But how much of a difference does weight make in indoor karting? First off, weight will generally make a much more significant difference in karting vs. cars because karts are many times lighter then even a small open wheel car like a Formula Ford. However, a recreational style kart is significantly heavier then a pure racing kart. A pure racing kart might weigh 180-200 lbs without the driver and while I don't know the exact weights of common rental karts, I'm guessing they might be over 50 lbs heavier. So, just considering the mass of an average sized adult relative to the weight of the vehicle, a weight difference in indoor karting will be significantly greater then in car racing and somewhat less then in traditional outdoor karting. This weight difference means that a lighter driver will be able to accelerate out of corners faster and generally archive faster speeds at the end of the straight, and thus faster lap times. The lighter driver will also have a huge advantage on a standing start.

However there is another factor that might not be as obvious. On a kart, more weight may actually mean more grip in the corners. This is particularly true on indoor tracks that have a very slick polished surface using rental karts with hard long lasting tires. The more slick the surface, the more of an advantage extra weight will be; on tracks with a conventional/grippy asphalt or concrete surface (indoor or outdoor), the effects of any extra grip may be negligible. So on a slick surface, is this extra grip enough to offset the disadvantage in power to weight ratio compared to a lighter drivers? From my experience, 99% of the time, no. Being lighter is still an advantage. However, how big of an advantage on a slick surface could depend on the specific kart and the track conditions.

Besides the track surface, the track configuration could also affect the size of the advantage of lighter drivers. From my experience the extra grip from extra weight is a more of an advantage in higher speed corners, so a slick surface on a high speed track would likely be the “fairest” for heavier drivers. A higher speed configuration also generally means less accelerating which also helps heavier drivers, even on grippy tracks where extra grip is insignificant. Naturally, most grippy tracks are higher speed so a heavier driver is not necessarily at more of a disadvantage at a high speed grippy track vs. a lower speed slick track.

Finally, a heavier driver also has more weight over the rear axle of the kart, which is where the only brake on most karts (and all indoor karts I've seen) is. To me, in theory this means a heavier driver will be able to brake better; however considering how marginally brakes are used in indoor karting I'm not sure if this effect is significant.

I have limited experience in traditional higher performance outdoor karting, but my feeling is these advantages for heavier drivers might not carry over to this discipline due to the lighter kart weight, much stickier tires and perhaps other factors, or at least be a much smaller effect.

In conclusion, lighter is faster in indoor karting, but maybe not by as much as you think.
Category: General
Posted by: Mike
So You Want to Be an F1 Star?

Here's a interesting article that provides some insight and details on the 1st red bull drivers search in 2003. 15 drivers were "scouted" and 13 participated (AJ Allmendinger and Ryan Hunter Reay didn't participate choosing deals in Toyota Atlantics and CART instead).

Most know Scott Speed eventually made it to F1. But what have all 15 drivers accomplished since then? Here's some stats:

As of 2010, at least 7 are currently racing in a major professional series - Speed and Allmendinger in NASCAR, Hunter Reay in IndyCar, Bryan Sellers, Patrick Long, Joey Hand and Paul Edwards in sports cars.

At least 5 went on to do some racing in junior European formulas after the driver's search, either as a finalist or on their own - Speed (F3, Formula Renault, GP2), Joel Nelson (Euro F3000), Grant Maiman (Formula Renault), Edwards (World Series by Nissan), Phil Giebler (International F3000).

At least 6 went on to do some racing in American junior formulas after the driver's search - Allmendinger (Atlantics), Giebler (Atlantics, Indy Lights), Rocky Moran Jr. (Atlantics), Hand (FBMW, Atlantics), Bobby Wilson (F2000, Indy Lights), Scott Poirier (Barber Dodge Pro)

At least 4 went on to do some racing in stock cars - Speed (ARCA, Trucks, Cup), Allmendinger (Cup), Boston Reid (Busch, Trucks), Moran Jr. (Busch North, Grand National East)

At least one is an instructor at Skip Barber - Maiman

Finally at least 7 appear to be currently out of racing - Giebler, Reid, Nelson, Moran Jr., Wilson, Poirier, and Michael Abbate.
Category: Racing Simulators
Posted by: Mike
Here's clips of decent (for me) laps around VIR in iRacing and in the real world.





And a few notes:

In iRacing the track, car and tires are always in the exact same condition. In real life, the track could be green or rubbered in, or slippery or grippy due to temperature and change in the same day. On top of that, there could be dust or even oil or something else slippery on parts of the track. The cars are matched performance wise pretty closely before each race weekend relative to each other, but not necessarily relative to other weekends and certainly not years ago. The tires could be full treads or more worn down, and I heard different tires are used in the summer series vs. winter (southern) series. All this means comparing lap times is much less meaningful in real life then in iRacing.

For the record though, the iRacing world record in the Skip Barber Formula 2000 car at VIR is just under 2:09 while my best time there is 2:11.8, 2.8 seconds off the world record. The real world lap record is 2:08.5, but the fastest laps of the sessions last weekend were mostly in the 2:13 to 2:14 range. In my best sessions I was about 4.6 seconds off the fastest times of those sessions.

For the track conditions and baseline the cars were tuned to last weekend, the cars seemed to have less grip and longer braking distances then in iRacing. The grip levels in iRacing seem closer to those with the national series tires from the videos I've seen. I also noticed the gear ratios in real car are a bit lower. Second gear comes a bit after 50mph, while in iRacing it comes close to 60mph. I heard the national series tire diameters are different from the regional series. This, in combination with the higher grip levels makes me think maybe the iRacing car is modeled after the national series tire, although the tire has full treads in the graphics like the regional series street tire.

Obviously the real car is more physical to drive, although I wouldn't consider this the main factor holding a sim racer back driving the real car. The G forces in the Skip Barber car are not that great (around 1.5g according to the accelerometer), so extreme neck strength is not required, although you can certainly feel the force. The forces required to turn and hold the steering wheel, press the brake and pull and push the shifter are all significantly higher then any sim setup I've played, although not so much as to require top physical condition to drive. And obviously, most people don't sim race in extreme heat, which can make a significant difference in terms of fatigue.

The brake pedal on cheap pedal sets is obviously not realistic. This makes it hard to practice releasing brake pressure, which is a major key of driving race cars fast, particularly a car like the Skip Barber F2000. The muscle memory of pushing down a pedal that requires much less force and moves more linearly with heavier braking does not help you that much for the real life scenario. Further, if you left foot brake in the sim but not in real life (the steering shaft is in the way on the real car and makes it difficult or impossible to left foot brake with adult sized feet), the technique for coming off the brake in onto the throttle is further irrelevant. I didn't find it hurt me; where the muscle memory I developed playing the sim didn't help at all. I'm thinking about investing in a more expensive brake pedal to practice this more realistically.

The sensation of speed is obviously something that you can only get more comfortable with more real life seat time. The fear of crashing (whether crashing and doing bodily harm or crashing and having to pay for damage) is real and keeps you in check.

I would say the physics of the car are well simulated. The effects of braking and throttle inputs on front to rear weight transfer feel very similar to real life – enough so that the sim and real life require similar techniques to drive. I think this is evident comparing the videos. You obviously can't develop the seat of the pants feel though.

As evident in the videos I posted earlier, the draft is huge in the real life skippy car, worth maybe 1-2 seconds a lap at a track like VIR. This means in the real car you can keep up with faster drivers by staying in their draft, pass more easily and adds additional elements of racecraft to the racing.

The track as I mentioned before is in my opinion awesomely recreated. The elevation changes do feel more dramatic in real life.

Do I think iRacing helped me last weekend? Certainly. Can all sim racers expect to be as fast as they are in the sim their first time in a real car? Certainly not.
Category: Racing Schools
Posted by: Mike
Here's a few clips from my Skip Barber race weekend.

I made a mistake on this video, the start is the last lap of the race; then it cuts to the first lap of the race.



This one is just the exciting photo finish!

Category: General
Posted by: Mike
Race 2 on Sunday went ok. The biggest drama was the initial start. As we creeped onto the main straight, the green did not come out, but I don't think anyone at the back realized it. Since I couldn't see the flagstand from the outside of the fourth row, I went when the guys in front of me went. As we approached the start finish line, the front guys started checking up and I barely avoided hitting someone but went off track in the process. On the second start attempt, I played it conservative and got passed by a bunch of guys on the start. By the time I worked back past a few of them, the guys that were around my qualifying pace were way ahead. I tried to close the gap but instead they found more speed and slowly pulled away. I finished 10th.

I was a little disappointed to not lower my lap times during the races although I did feel like I was improving. Watching the video confirmed that I was indeed carrying more speed through a lot of the corners, but I had also toned it down a bit and took fewer risks in order to finish the races. I didn't want to throw away a decent result for my first weekend nor could I afford a big crash. So although the pace was about the same in practice and qualifying I was doing it crashing, spinning or going four off in every session, whereas in the races I was able to run the pace consistently.

Although I'd hoped to be a bit faster, my pace is not too far off where I want to be. Obviously I didn't expect to be competing for the win in my first race, but I have no reason to believe I can't make it there eventually, and possibly make it there pretty soon. Although five seconds or so off the pace may sound terrible I have no problem admitting it. These are very challenging cars to drive on a very challenging track against some of the best drivers in the country, most with significantly more experience then me.

I'm itching to get back in the car, although that probably won't be for a while with my budget.

I'll post a few video highlights of the races soon.
Category: General
Posted by: Mike
I tried hard today to put my “incident” from yesterday morning behind me, and have to say I partially succeeded. After today, yesterday feels like last month.

I was reminded that spins or four offs in qualifying would result in starting at the rear of the field, so of course I went out and promptly spun the car in the “roller coaster” after only a few laps. I decided to find a gear and drive out of it before even coming to a complete stop and act like nothing happened. Apparently someone noticed so I would start the first race DFL, 15th. I was pretty happy about setting a lap “only” 4.6 seconds adrift of the pole time, which would have put me 9th on the grid.

I was extremely nervous at the start, I had never raced against this many cars before, in this level of competition or on a track this challenging. In two and a half days, I'd only made it one session without spinning, going off, or hitting something, so how was I supposed to finish a 30 minute race without any mistakes?? I was actually kinda happy about starting last because it was less pressure then being in the middle of the pack. For the start and the first few laps, I played it conservative while I worked past 4 cars that were a bit off my pace. Next up were a few guys that were around my pace (and that I'd somehow managed to out qualify on paper) but they were now half a straight ahead of me. Fortunately(for me) on lap 3 or so someone stuffed it hard and the full course yellow allowed me to close up.

One lap after the restart, I was able to pick up a monster draft and make a pass for 8th place on the back straight. Once ahead I was not able to pull away. The following driver was faster then me in a lot of places, although he did not seem to be able to get a good draft on me. With only a few laps to go, he got a good run and took me back on the back straight. I put my head down and tried to keep up. Although he was gaining on me in a lot of sections I was closing quickly up the esses and on the long straights were I was able to stay in his draft. On the last lap down the back straight I got a good draft and he rode the middle of the track. I decided to go to the right but his line “wobbled” a bit, and it got kinda tight; I decided to play it safe and back off. I knew my final chance to get by would be the race to the line out of “hogs pin,” the final turn and perhaps the most challenging of the whole track. Somehow, when it mattered I managed to carry more speed then I ever had through and out of hogs pin and was right on his gearbox. I sucked up and popped to the outside and we drag raced to the line, crossing side by side. The time sheets showed he beat me for 8th place by 7 thousandths! It must have been inches on the track.

Although I didn't beat him to the line, what an exciting ending to my first race in these cars! My pace is also not far off where I want to be. Hopefully I keep if off the walls again for the last race tomorrow!