Quote:
Originally Posted by The HACK
We're about to take this thread off topic but...
I'll have to find telemetry data to support my claim, but if I'm correct, you'll see speed and lateral G ramp up fairly smoothly, but once it gets to the limit of the tire's grip, you'll find a really good data acquisition graph to show "vibrations" or what I called jaggedness soon after turn-in, or after the suspension sets. I recall someone relaying a story about Ayrton Senna, during the "turbocharged" 4 cylinder era, his engineers were looking at his throttle telemetry and was puzzled to find that through certain turns it looked like he was modulating the throttle very rapidly, and when the engineers asked him about it, he said that if he had gotten off or stayed off throttle, then the turbo would take a while to spool up on the exit and he would lose precious time exiting the turn. So in order to keep the turbo spooled up, he "jabs" the throttle repeatedly to ease the acceleration load while keeping the revs and exhaust pressure up to keep the turbo loaded.
Seemed counter-intuitive at the time, until I took a ride with a friend that was driving in the Speed World Challenge at the time. I noticed that at the exit of slow speed turns, he would "see-saw" at the steering wheel. I was a bit puzzled, since throughout my entire career we were told "smooth is fast," and here he is, the prior year's SWC rookie of the year, at one time my instructor, who repeated that mantra to me before, doing exactly the opposite. So I asked him about it once we pitted the car, and he said, basically, at the limit of the tire's available grip, you can temporarily increase the amount of lateral grip available to you by straightening out the wheel a little bit and then return it back to the previous "set" position, and if you do this rapidly in very small increments, you can continue to keep the suspension "set" without unloading the weight of the car, but decrease the lateral load on the tire enough to keep it from "losing grip" by going PAST the optimum slip angle of the tires.
So perhaps the way I explained it in the previous post does not describe the process in the correct manner, but the basic concept is the same. You can prevent either end of the car from losing grip, or going into "understeer" or "oversteer," by sort of "chopping" at the wheels a little bit at a time. But you must do this just right before the tire transitions from static to kinetic grip, otherwise the benefit of it to "going fast" is all but eliminated once you're in kinetic friction (because the act of straightening out the tires will only bring it back from kinetic friction coefficient to static, rather than move that boundary to a higher speed threshold).
But, regardless, in order to execute said maneuver, you must be able to FEEL the car right before either end of the tire looses grip, and do the see-sawing of the wheel before the car pushes or starts a spin. And that ability comes from having done a tone of wet skidpad or karting IMO, since both will give you more opportunity to explore that boundary and find ways to expand it without wadding up your car. If you can feel the level of grip on the contact patch through your hands (for the front wheels) and your @ss (for the rear wheels), and you can accurately predict when either end is going to lose grip, then you can safely try and see if you can retain more speed from turn-in to exit by carrying more speed into the turn and using your hands to "add grip*."
*Using your hands to add grip is still the most accurate and easiest way to visualize what I'm talking about, even though it technically and logically does not make sense.
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Yeah, I wasn't sure if this is what you meant exactly. This is a very, very advanced technique. Hugely, HUGELY helpful in a FWD car. I think the best way to describe this is in a single sentence, not an essay.
You are correlating the maximum amount of grip with the minimum amount of steering.
When you reach the limit of grip the best thing to do, assuming the front of the car is washing out first (that is HUGELY important), is to reduce the steering angle. You will keep the same arc and scrub off less speed. If you are driving competitively it also saves wear on the fronts and makes the car more adjustable to other cars. The best way to think of it is like this. When driving a perfectly balanced rwd car, lets say an S2000, around constant radius sweepers ie: Turn 2 at WSIR, the car should be in a perfect 4 wheel slide. The only steering necessary is slight countersteer when the rear starts giving up quicker than the front. When you say to reduce steering, you are doing the EXACT same thing, just for the opposite end of the car. Think of it as countersteer for understeer (if that makes sense LOL).
However none of this adds grip, the goal is to remain at a constant grip throughout the corner because while it is not possible to add extra grip, it is possible to lose it. I'd love to see that telemetry if you have it.
One final way to look at this and what the normal drivers reaction is and then I'll shut up. When your car loses grip at the front end, the car goes straight. What most people do is add more steering and more brakes. Think of this like bicep curls. When the car is understeering it is like your last rep. You are struggling to get it up but are failing half way. Adding more steering is like adding more weight. You are requesting more grip that wasn't there in the first place. If brakes are added in the extra steering angle eventually grabs and there you have snap oversteer.