mark kibort

Mike, This is not about shifting and taking the time from accelerating. its about being in the appropriate gear to maximize control and HP. it's a tool. its one i like to focus on besides line. you can argue it all you want, but in the end, no one that is fast, doesnt utilize it when they can . in this case, its a simple change, and one the OP can do with no issues. sure there are instances where you dont want to be shifing to upset the car. I do i, for example, in the the turn 11, 12 at Thunderhill for that reason. This is NOT the only way. It's advice and a tool in my tool box to help and should be taken as such. it's obvious to me, and might not be to you. so you can either take it or ignore it.

there is no reason to sacrifice 30-75hp for several seconds, up to 4 in this section and up to 8, over a lap , by being in the non optimal gear. (not to mention the added control by having the RPM in the higher range during turn entry) if you have one... im interested to hear it.

Gofishracing

What lap times & who does car set up? I'm there this coming weekend. I'd like a less time in the left hander tip.

MSR Racer

In drag racing

ProCoach

The car did near 1:00.XX flat with the previous owner and previous setup, without "shifting down." These laps are some ways off that. The new shop, of course, has a laundry list of changes they'd like to make, but as we know, there's always some tangible gain in the driver due to comfort, confidence and learning the timing of control input versus response.

The tip is very old. Visible in Skip Barber's video by Carl Lopez many, MANY years ago. If Bruce MacInnes is there, ask him. He taught it to me. Data confirms it.

This is a pretty faithful execution of what I talk about with drivers I work with at LRP. Ben had never raced a car before beginning work with me in 2010 at Summit Point, now he's one of the best I've ever worked with.

Start at 8:30, where he is following the legendary Rick Bell, one of the masters of Lime Rock for forty years, in a Formula Atlantic (400 lbs lighter).

This car is 70-135 bhp down on the others (different class), has a fair bit of understeer (he could do better carrying the brakes in longer to get the car to turn quicker), but the geometry is, for the most part, correct...

Veloce Raptor

+1 that's it right there !!

AdamBrouillard

The problem many people have with the left hander is the natural instinct to want to go out wide to set up for it. The trick however is that as you reach the outside curbing of 2 you have to understand that you are already turning in for turn 3. Try to have a steady increase in steering from the exit curb of turn 2 to the apex of turn 3. The end result is that you should stay quite close to the inside curbing leading up to 3 if done properly.

There is a video that explains this on youtube. It was done in an mx-5 in iRacing, but how to approach turn 3 (as well as the rest of the track) is explained.

ProCoach

The former makes no sense. You know there is between 375 and 450 feet between the exit of Big bend and the entry of the Left Hander? You know that the Left Hander is MUCH more than a ninety degree turn?

The latter approach would makes you slower, later in the turn. Precisely the opposite of what you want in order to optimize the Right Hander onto No Name.

Adam, have you raced or driven at Lime Rock, other than virtually? Just a question...

ProCoach

Not only that, but the radius of this corner is ANYTHING but constant...

There is the seductive entry. Then, the "stretched," middle center section where most are "dead in the water." Then, there is the trick, tightening end, culminating at the end of the inside curb...

No, your "trick" is what was a quarter of a second slower in the OP's original comparison. Driven by someone I respect very much and who knows that place.

AdamBrouillard

The length doesn't matter. For a slower car, the apex of 3 is right at the 90 degree limit. For a faster car, the apex is somewhat later and then turn 3 starts to become a double apex as you start bumping up against the inside on the approach.

ProCoach

You're saying the straight doesn't matter? And that there's a difference geometrically in the line between the faster car and the slower car? Nah, that's ok. You do your thing and I'll do mine...

mark kibort

So, all that means if if he downshifted, to a gear that wasnt well below the optimal HP range, there would be more accelerative forces, not endangering any control capabilities in the turns, for several seconds. i cant think of any reason that you would not want MORE power when the wheels are straight. its not a shifting issue, as that is done before the turn.. AND, being in a lower gear around turns allows for better modulation and control
so if he ran a 1:00 , he might run a 59.5 using my advice. You wont know until you try it and see the data.

coincidentally, your video makes my point exactly AND the RPM range is the same as it is for the CaymanR. keeping the RPM in the 6k range is what he does and what the OP should do as welll. notice how he approaches turn 1 and the slow sections after. all downshifting, and keeping the RPM in the 6k range. again, by not downshifting to 2nd in this area, you run the car at a 50 to 75hp deficit for a substantial amount of time when the wheels are straight. having the car in the 4000rpm range for the caymanR or 3500rpm for the boxster, is just a waste of the HP you have available and will decrease segment times and lap times

mark kibort

no, actuallly in both drag and road racing. if you dont think you need power, then just stay in 4th an entire lap and see what your lap times are..

Veloce Raptor

Peter, you and I are totally on the same page. And coincidentally we have both driven, raced, and coached Lime Rock. Imagine that!

ProCoach

AdamBrouillard

Yes, there is a difference in the ideal lines between cars of different acceleration potentials. Higher acceleration potential cars need a relatively later apex. In this sequence, there technically is no straight, at least for my example car. You can see in the photo how the exit of 2 goes directly into the entrance of 3. In other words, there is no point where the driver should be driving perfectly straight. The example car is quite close to 90 degrees of entry so in a higher acceleration car you probably would have a bit of driving straight after coming out of 2. Sorry if this last bit is confusing. I'm trying to pare down the explanation.

Really the idea is to create your own ideal line with the given track. You could do this with 3 cones per corner. One where your entry starts, one at the apex, and one final cone where you are driving straight again. If there is space between the final cone and the first cone of the next corner then you have a "straight." Your "straight" might only be 30 feet of driving diagonally across the track sometimes through.

I'm not really sure why you are trying to argue with me though. Rick Bell in the video that you used as an example is doing as I've described. Why are you so mean sometimes? I've never came on here and said you or anyone else was wrong about anything. I just try to help people understand the why behind all this as that part very much interests me.