WDMS Chapter 189   -   18 November 2011

A LAP OF DKC ! ! ! ! !

Hi there!

 

If you are wanting to run DKC or perhaps already run there and are looking for my take on the track, here it goes. I don’t purport to be the master (I’ve only been there three times now!!) but I think I’ve got the basics down and I know my next visit I’ll be working on going faster.

 

Some background on my karting (skip this paragraph if you like): Not much. I’ve run a few kart tracks in rental karts, did F1Boston and an enduro at IronRock (Austin) years and years ago and then one event in Miami during the Rolex Grand-Am event there in early 2008. Prior to the Vorshlag Karting challenge back in the summer, I’d not been in a kart for over 3 years. Also, I’ve NEVER driven karts this fast. These karts flat smoke the others I’ve driven. It is a huge difference. Two weeks ago Cody and Fair and I went and did a three-race night and swapped the same three karts every session and we were the only ones on the track. Awesome fun and we got to lead-follow and we all learned better lines and got faster. After the event last night (9 TAMSCCers living in the DFW area) , I am now ranked 66th out of 6,239 (98.94%) and at the end of this third visit I’ve now gotten 10 races in with a best lap time of 72.0 (1:12.0). No, I don’t think that is a lot of experience either, and there surely is room to go faster, but I’m writing this to reinforce it to myself and for some discussion points with the aforementioned TAMSCCers. I’ll go over it before the next visit and work on areas to improve. I do this with full size tracks also and it stems from the SCCA magazine’s old ‘Flying Lap’ series where they would have an expert talk you around a lap of a different track each month. I wish SportsCar would bring that back!

 

There are two types of karts at DKC. Oversteering karts (loose) and Understeering karts (push). An oversteering kart leaves the racing surface with the rear tires first, while an understeering kart leaves the surface with the front tires first. Interestingly, I’ve cut my fastest times in karts that push. Theoretically a kart could be neutral I guess, but myself and the folks I run with have never run one so I’ll keep my points to a ‘loose’ kart or a ‘pushing’ kart.

 

The benefit of a loose kart is that it will typically turn in really well. You can be at full throttle and ease some steering angle in (the faster you are going = the slower rate of speed I turn the wheel) and the kart simply changes direction. This is super nice to hitting the exact apex that you are looking for. The negative corollary to this is that the rear tires will ‘step out’ and you have to countersteer in order to ‘catch it’ so you don’t spin out and get t-boned by the guy behind you. The quickest way for me to drive a loose kart is to really focus on turning the wheel only enough to make the corner arc that I want and keeping the rear tires in line. On 1, 5, and 7 occasionally I’ll be barely drifting the kart and as long as you’ve got the power on and the engine is pulling good I really don’t think I’m losing any time. Most frequently I find myself turning in initially and then as soon as the kart takes a set I’m actually just *barely* counter-steering all the way to the track-out rumble strips on corner exit. That is a sweet feeling when you get all those things right to produce that. This means your braking point was right, your kart was exactly where it needed to be and at the exact speed when you turned in the exact amount to produce the exact arc and got on the gas exactly at the right spot with the tiny drift angle in order to do that corner ‘right’. 1,5, and 7 are long corners and I’m riding those arcs for a long time praying I got the entry right because if I did then the exit takes care of itself. Obviously, you are ‘riding the edge’ the whole time around and if you can’t balance that fine line between grip and slip then you’ll likely spin.

 

The benefit of a pushing kart is that they rarely spin and when you get on the gas they put down power well without the rear ‘stepping out’. While I always feel faster in a loose kart, my times in a pushing kart have always been my fastest. Food for thought. The problem with a pushing kart is that they don’t ‘turn in’ when you want them to. You get up to the corner and turn the wheel and the kart only turns a fraction of the amount that you need to hit your apex. Obviously, to get a pushing kart to turn in I had to figure a way to get the darn thing to rotate so I could hit my marks. Years ago I drove a rally car and the ‘Scandinavian flick’ was the trick employed to help get the car to rotate on adverse surfaces. It works on karts too! As I head down to T1 I get to the far right side of the track to setup for the left turn. Just before I need to turn left, I actually turn a TOUCH to the right, put the right side tires on the rumble strips and then in one smooth-continuous-motion turn back to the left. The kart will then rotate and you can then ‘ride the edge’ of grip. I personally find that ‘riding the edge of grip’ on the arc is much easier in a pushing kart than a loose kart. It was while driving a pushing kart that I realized using the rumble strips on entry seemed to be worth a little time. Since the track was designed to be run both directions, you’ve got rumbles on entry and exit and while another 12” of track may not seem like much if you’re used to driving cars, they are indeed helpful in a kart that is only 40” or so inches wide altogether.

 

Costas' Theory of Going Quick at a Kart Track: Just like a full size track, getting on the gas the soonest is the big deal. I’ll gladly give up the ultimate-late-brake mentality for the assurance of having the kart exactly where it needs to be at exactly the right speed so I can turn and plant the throttle at the right moment. With the surface a bit bumpy in some of the brake zones the ability to wait until the absolute last moment and then get good braking performance is pretty daunting. Yes, I brake pretty deep, but my mind is mostly focusing on getting to that turn in point with the kart stable and ready to accept power. In T1, I typically lift and ease onto the brakes sooner than anyone else. I am braking before the rumbles. I also turn in sooner than most, but more on that later. My mind is constantly seeking that point where I can put the gas down and leave it there. Lastly, and this is just kart-etiquette, but if someone catches you, let them by so that: 1) you can follow them and learn their lines and 2) you won't be 'that guy' who blocks and other karters can't stand. 

 

Phew…still with me? Okay, let’s go make a lap!!

 

The timing strip is next to the tower on the longest straight and also where standing starts are done so we’ll start there and if you look at the accompanying map the turns are labeled 1-13 and also the chicane. Just like Road Altanta where ‘the esses’ don’t have numbers, DKC has ‘the chicane’.

 

 

T1. (T1 is a brake, turn, go corner) So, assuming you did the 10-13 complex right, you’ve got the kart topped out as you are coming up on the 180 sweeper that is T1. I line up far right, ease out of the gas and onto the brake a bit before the rumbles and ease to the right onto the rumbles and by the halfway point in the rumbles I’m already turning and going back to the throttle. T1 is a smooth arc, but it seems like two 90 turns linked (like T5 or T7). So what I do is come REAL close to the curbing on the first 90 and then REAL close (or slightly run over with ¼ the kart) to the second 90 and then I typically track out and end up on the last ¼ or so of the rumbles. MY THEORY on T1 is that you’re turning 180 degrees and there is no point in going further out than absolutely necessary. If I turn later, I’ll be going the same speed anyway, so I might as well turn around soon and save the distance since the speeds are the same. Added Distance does not always equal added time, but in this instance, I think it does.

 

T2. (T2 is a no-lift corner stay completely on the throttle) So you did T1 exactly perfect and tracked out to the last part of the rumbles and you have T2 in your sights. Migrate back to the left of the track and turn in earlier than you think you should. Clip the kerbing if you need to angle the kart more, but if you rotated the kart at the right spot then you just missed the apex kurb and your trajectory is looking bad. You indeed run over the rumbles on exit but the track comes back in front of you in time to straighten up and brake a bit. While this is a 90 corner, you can treat it like a 75 degree corner with all the extra track they have there. The exit of T2 directly sets up T3/4 so as you line up for T2 glance behind you if you can. You will need to choose if you are going to run T3/4 OFFENSIVELY or DEFENSIVELY.

 

T3/4 (T3/4 is a brake, turn, go corner). DEFENSIVE: You may lift off the throttle for a moment near the apex of T2 to tighten up your exit line and from about the middle of the track brake fairly hard till you get about even with the corner and then go to the gas as you turn in, climb over about half of T3 inner kerbing and straight line it as much as possible to go over about ¼ of the T4 kerbing as you head to the track out point and setup for T5. Slow enough before you initiate your turn in T3 so that when you plant the throttle it can stay there all through the T3 exit and T4. If you have to lift again you will hand someone a pass on you going into T5. OFFENSIVE: Your tail is clear and you have a victim in from of you (or are simply going for a fast lap time). Absolutely do not lift for T2 and use ALL the track out rumbles on T2 exit and you are carrying a LOT of speed in the short chute approaching T3/4. Stay wide, brake quickly and straight and stay 2+ kart widths away from T3 until you turn right and plant the throttle. Run over the last portion of the T3 kerbing as you pick up speed and run over the center part of the T4 kerbing on your way to T5. You can’t run a wide entry line if someone is behind you as they will stick their nose in and take the corner, but you’ll both be slow on the getaway. In one event I was catching two guys and they battled in T3/4 and I ran it very offensively and motored by both of them on the way to T5 as I’d gotten on the gas before either of them since they were jockeying and lifting in the middle. I realize heat of the battle and all, but you’ve got to weigh where to pass so you don’t open yourself up to a pass either. Since the offensive line is keeping the speed up to the last moment and you’re running out of track both laterally and forward at the same time and the barriers are close, this is one of the most exciting corners on the track (to me). MY THEORY on T3/4 is that if you’re solo, you can go very fast through T2 and carry that speed further and later then brake and be on the gas sooner to carry that speed to T5 as you ‘straighten out’ the T3/4 since you take the ‘wide entry line’. This is opposite of T1 where in this case (T3/4) I’ll knowingly go a slightly greater distance, but since I’m carrying more speed in and then carrying more speed out, I’ll take the distance route. If you have to block someone in T3/4 your speed on that 250’ straight following the T3/4 will be horrible. Hopefully the guy behind you did not go wide and get a run on you coming out.

 

T5 (T5 is a no-lift corner, stay completely on the throttle). This is not a 90/90 corner, it is more like an 80/90 corner, but treat it like T1. Stay wide, get barely on the rumbles and I don’t go any farther than I need to so I turn in early enough to kiss the first inner kerbing and then usually that puts me on an arc to run over the second part of the kerbing with maybe ¼ to 1/3rd of the kart on the way to the outer rumbles track out point. MY THEORY: Again, like T1, I vote for the ‘least distance’ option and that means turning in early and clipping the apexes. Any extra distance is simply extra time on the clock.

 

Chicane (The chicane is always a no-brake corner, and usually a no-lift corner). Depending on the kart, I’ve typically been able to take the chicane flat-out. I seem to have to turn in sooner than I think I should but it ends up working out. About ¼ of my kart runs over the first (right) kerbing and how well it takes a set, how hot the tires are and how balanced the kart is, determines if I just kiss the exit kerbing (on the left) or run over it some. Occasionally I’ve had a kart that was stubborn to rotate and a quick lift and quick re-stab of the throttle can allow it to rotate with a miniscule loss in time. Since there is very little room for error this is one of the most exciting points on the track for me along with the offensive approach for T3.

 

T6 (T6 is a no-lift corner). Simple left turn of about 75 degrees. After the chicane, you’ll be on the right side of the track and since you’re picking up speed still, turn in early and put about 1/3 of the kart over the kerb to shorten the distance to T7. As you approach track out, glance over your left shoulder to check for faster karts catching you.

 

T7. (T7 can be a no-lift corner). If it all goes right, flick the kart onto the right side rumbles as you approach T7 and turn in early. Early enough to kiss the inside kerbing on the first 90 degree part. Keep the arc tight and come within a karts’ width of touching the second apex. Any further away from the kerb and I feel I’m losing time (a’la T1) and there is a LOT of track out as the second part of the corner is not a full 90 degrees. Done right, you’ll end up at the track out point right where the right side rumbles end and be on T8 in moments. For me, if I’ve got the entry a bit screwed up, I’ll lift off the gas a little (not all the way) and tighten up the arc to put me back on line. Hanging the tail out here, or going deep in the corner before starting the turn will really kill you here. MY THEORY on T7 is the same as T1. Forget the uber-late-brake crap and get the kart rotated early and kiss the apexes and get going.

 

T8. (No lift). If you did T7 right you are already upon T8 as you hit the track-out point so let’s keep our ‘shortest distance’ theory alive and put half the kart over the right side kerb and then let the kart track out to the left side as you setup for T9. Too many folks try and get back to the left side of the track to start T8 and in my eyes that is a waste.

 

T9 (T9 can be a no-lift corner). T9 is greater than 90 degrees and leads you to what I feel is the most critical part of the track (T10/11). I take the kart all the way to the left and turn in about where I would if it was a 90 degree corner. If the kart is handling well, it will stick and you’ll use every bit of the rumbles on the exit. Like T7, if I find I’m a bit out of place, a quick lift and then back down with the throttle gets me exactly back on line with minimal loss of time. MY THEORY on T9 is that even if I have to lift a bit, I’d rather have the kart be exactly where it needs to be than have speed in hand and an out of shape kart.

 

T10/11. For me this is the corner that I really get my eyes forward and my visual sampling is by far the highest for the lap. This is truly similar to T3/4 but on a slightly larger scale physically and a much larger scale as far as potential to help/hinder your lap time. The earlier I turn in for T10, the longer I have to wait to put the throttle down. My goal is to be at a place/time/speed in the kart going into T10 that I can stay a bit wide and slow down and then when I go to the gas, I can keep it down (exit speed is life) from there till T1. If I go in deep but stay wide left, then when I cut to the right, I can floor it. I’m going slowly enough and it is straight enough that I can keep it floored from the exit of T10 around the T11 kerbing and the kart will arc out to the rumbles on the right for the short straight to T12. If I have to lift off the gas through any of that then I did it wrong. If I turn in early and hug T10 kerbing and have to wait until I am in T11 till I can give it all the throttle then I did it wrong. For me, the right way through this corner is the one where I can go full throttle the earliest and not lift. Similar to T3/4, the defensive line here keeps folks behind you, but you sacrifice exit speed. I catch a lot of folks here and lay back, run the proper ‘exit speed’ line and walk them down the long straight down to T1. This takes a lot of discipline because lots of folks want to go ‘around’ the corner as fast as possible, but I feel that I’ll give up the ‘speed’ of T10, for the exit speed of T11 that carries me to T1 faster. MY THEORY of T10/11 is just that. Mine. I’m sure there are a lot of ways to do this corner, but considering its location and effect on lap times, I don’t care if I go in a touch slow, I’m coming out as quick as I can.

 

T12. So I come out of T11 picking up speed and T12 is just ahead. This is now just as critical as T10/11 because as I was disciplined and worked for good exit speed I can easily throw it away here and kill the lap time. The rumbles on the right are wide so get all the way over on them. T12 is greater than 90 degrees and by the time I get there I’m at a velocity that is very close to optimal for the corner if the kart is handling well. Again, it is time for discipline. If my kart is not exactly where I want it, I will lift for a moment in order to get the kart positioned perfectly for the right arc. Carrying extra speed past the apex just means you’re going to go wide. In my experience, dropping two off does not hurt your time. Four off definitely does. If my visual sampling of my current arc tells me that I’m going to do more than a quick drop past the rumbles, then I come off the throttle just a touch to tighten the line and then re-drop the hammer. It is my personal thought again that I’d rather be on the right line a tiny bit slow than be going faster in the wrong direction. Turn in early and from the very outside of the rumbles and make corrections on entry (pre-apex) since post apex corrections seem to be more costly (my theory). With a good kart, this is a no lift corner and the third most exciting (potential for major screwup) corner on the track after the exit of T2 and the chicane.

 

T13. A dog-leg left that you won’t lift for. I kiss the inside kerb or run over it a bit. Easiest corner on the track. Watch your back because if you didn’t get a good exit from T10/11 or had to lift much in T12 another kart may be coming up fast.

 

So there you have it. That is what I'm typically trying to do when I'm out there. I've been three times and hope to go again soon and shave off more time in the quest for quickness!