Saturday, February 2, 2013

Random Radical Information

Initial Brake, Off brake and “Roll Around”:

You made good progress over the weekend, even though you may feel that your performance on Sunday was a little lack-luster. We were working on your “rolling speed” through the corners (Turns 1, 2, Bus Stop, and The Carousel (right hand corner after the Bus Stop).

You did well to improve your coast period by getting off the brake sooner. There’s still room for progress though! To simplify the concept, there’s a term I use when coaching drivers in the FF2000 series (similar car/driving style to the radical):

“The way to drive this car fast is to brake later than everyone else, come off the brake sooner, and get on throttle later.”

This is a little less accurate in the Radical, but may illustrate how important the “rolling speed” or coasting speed is. The best way to enable the car to carry speed through the corner stems from the “Quick Switch” or I.B.P. (Initial Brake Pressure).

As noted earlier in the report, your Foot Work is good, and you could get even better!

In Grant’s last report he mentioned a different brake release pattern than the Pro Mazda car, and we think the Radical has a different “aero map”. After driving, I can guarantee that the Radical has a different (better) Aero Map! When you are really late on the brakes in the Pro Mazda the car primarily stands on it’s nose with the I.B.P. When you are really late/hard on the brakes in the Radical the front tires get the brunt of the load, but the whole car lowers (at least that’s what I felt)! Braking the Radical reminded me more of an Atlantic or an F2 car than the Star Mazda! What does this mean to Dave?

The harder your brake Initially, the more grip you have! The same is true in the Pro Mazda, but to a lesser degree.

The picture above has me compared with you braking for Ego Check. This particular lap I braked too early, but with a much harder I.B.P., meaning you can brake harder.

The pictures above are my best Ego (Turn 3) compared with Your best and 2nd best. I could’ve braked harder still. A slight time loss from a more rapid decel but time gained at exit. The harder brake enables the car to corner and get a better exit. Also interesting to note how early you crack throttle subsequently getting full throttle later.

You and I also run a slightly different brake bias as a result of having different Initial Pressures. The harder initial hit of brake, the more a driver loads the front tires. Remember me radioing, and asking you to go back 1/2 or 1 turn in brake bias?

The arrow above points to a little bit of rear brake bias on the I.B.P. on my hardest brake entering Ego. I subsequently moved the brake bias 1/2 turn to the front. You had a little front lock up, later in the weekend (after the change).

The Radical has good brakes.. Slam them! :)

Off Brake and Roll Around

As noted you made good progress, and were the fastest driver entering Turn 1 by Sunday, and there’s still room to improve.

The pictures above are you vs me entering Turn 1. Given I braked a little too soon, but note how early I’m off the brake, and how late I am to power. The bottom line is gain/loss from Chicane to Exit of Turn 2. I spend more time off brake, and coasting which nets a good gain. Also note the decel I have on coast (from scrub and engine braking). PFM’s don’t do as much.  If you would brake as late as you do for Turn 1, but simply come off the brake there would be no touching you!

Back to Power as a Habit or to Balance:

We spoke over the course of the weekend about “why” a driver get’s back on throttle, and generally speaking you have good foot habits (reference the good Foot Work note earlier). When I rode with you I noticed a trend related to your entry/rolling speed. 

If you over-slow for a corner you get on the throttle immediately (very little if any coast period).

I think you can use the above information to help with the “roll around” speed. If you notice your inclined to get back to power early, that means you over-slowed. Brake later or come off the brakes sooner on the next lap!

With that said, if you’re driving either the Radical or the Pro Mazda and the car needs rear-end grip, getting back to power early is a good thing (your Radical currently has a little Under Steer in faster corners or on throttle).