Robert Henriksen

That's why Sunday has a bunny-killer splitter on the front of his car. The bunnies eat the tire worms, and he wants to be sure the worms stay on the track to throw off the cars behind him.

SundayDriver

Why I think that Robert and the Professor are on to something there. This is starting to sound like an old Gilligan's Island episode. We are stranded and ColorChange is just trying to get us rescued by drawing a help message in his charts. And all this time I thought they were worthless but are really a clever attempt to get help. I took one more derivative of his data and found the secret message from CC.

Bob Rouleau

Color - what we agree on is that the DAS does not provide a meaningful clue as to the fastest line - multiple solutions are valid from a G Sum perspective while a sub set of lines are fast.

A simple segment timer would determine the fastest line with a lot less work would it not? Once you've found the preferred line for your car, I can see how data analysis can be used to tweak it to near perfection.

I do segment timing with my video camera and a stop watch. Simple and inexpensive.

Now, back to tire worms, camshaft borers and other life forms that plague racing drivers.

Regards,

M758

Bob,
Where do brainfarts fit into all this? I once had an off an fellow driver said it must have been a brainfart that caused it. I never knew what he meant, but now I am thinking it may be something like these tire worms. I be glad to know if they could cause an off 'cause then it would not have been my fault.

Sunday...
Think I could find evidence of a brainfart attack on my DAS? Would that show up on my jerk curve?

SundayDriver

I am pretty sure this all fits together. If you don't have a bunny killer splitter, then the tire worms get in your ear and fart. You know the rest of that story.

Once that happens, they go all the way through, come out the other side, get into your DAS and change your name to Colorchange.

ColorChange

For those who are serious, I would be happy to send you my data so you can perform your own analysis and get comfortable with these concepts. The analysis software is free from

http://www.aim-sportline.com/

Send me a pm with your name and e-mail address and I'll send the data I have, for a Lambo, 996tt, and a 944S.You will be able to see for yourself if anything I have ever said was doctored or "overly filtered" as has been implied by some.

ColorChange

Bob, you cannot as accurately tell which line is fastest using a stopwatch as a DAS because you can't tell how close to the fc the driver was on each particular line, exactly what his exit and entrance speeds were, etc. This is important and the DAS knows it all. Your way can work it is just inaccurate and highly inefficient in comparison. A DAS isn't the only way, just the most accurate, efficient, ... best way!

Furthermore, the DAS can measure numerous other variables, optimal shift points, H&T downshift gear matching capability, engine performance (intake charge temps, ...), brake cooling performance. I'm installing two infrared sensors for caliper and rotor temps. These will later be used for turbo charger temps, exhaust temps, and many other temps of interest, aero effects, suspension optimization, etc. etc. etc. The list is nearly endless. This is precisely why you see truckloads of engineers working on DAS systems at F1. They are immensely valuable tools that add FACTS to what otherwise becomes opinion, guessing, and too often just plain BS spread by ignorant, low character fools.

SundayDriver

OK, that does it. Those are fighting words and that kind of personal insult makes my blood boil. I, for one, am not going to allow you to say that about my friend Fishman. Just name the place and DJ is gonna whup your itty bytey butt.

ColorChange

OK Mark, you made me laugh. I admit it.

Greg Fishman

Bob Rouleau

M758 (may I call you M for short?),

Brainfarts are a common problem. There are many theories about the cause. Beer can cause them as can distractions like pit babes and grid girls. No matter what the cause, DAS-Pirin is the cure. Yes, DAS-Pirin is doctor recommended to relieve the suffering caused by brainfarts. Endorsed by engineers, DAS-Pirin has been shown by at least one engineer to cure bad driving, improve smoothness and prevent recurrence of brainfarts. Ask for it at your neighborhood track today!

Premier Motorsp

Why is Colorchange getting so much flak? He is being scientific and learning in a way that suits him. What is the problem with this?

In skimming through this thread I see he has a few things dead correct. The most important is that the concept of slow-in fast-out is dead wrong. Usually it takes about 10 years before you figure out how wrong this advice is.

I think the G-sum IS a great way to evaluate a driver. It shows, more clearly and easier than anything else, whether the driver is on the limit or not. The failing of relying on G-sum is that the line choice is still a question, and Colorchange readily admits that.

From watching the video, I would first advise Colorchange to take his car to a racetrack and stop wasting time and money at Gingerman. That Turbo is a bull in a chinashop there. Secondly, most of the apexes and turn ins are too late. Good beginner DE technique, but it sacrifices all the entry speed. Thirdly, brake earlier. Since the brakes are not up to 100% use, why not ease off them, take the small hit in lap time, but have functioning brakes with which to perfect the trail braking technique. The decel from turn-in to apex is what separates the men from the boys, so practicing this is critical.

Also, get some Michelin PSC's. Racing on street rubber is just frustration.

Chris Cervelli
Premier Motorsports

SundayDriver

If you took a look at his history on Rennlist, you might feel he is being treated very gently here. His first theory, that I saw, was to threshold brake to the apex. When he got resistance to that, he resorted to personal attacks, name calling and obscenities. In his subsequent threads, anytime someone disagreed, at best he wasa arrogant and told them they were not smart enough to understand and at worst, launched more personal attacks.

Skimming through this thread does not paint a complete picture.

ColorChange

Chris, thanks for the support and I agree big time!

I know the tt is hemmed in at Gingerman but I think I need to get better before I'm doing 170 at Road America. I'm hoping next year as I'm not ready this year.

OK, I'll work on modifying the lines. That is an area that I have little confidence in my own ability to asses right now, especially since this is my first time in a 911 and they do drive differently.

I also agree about your braking comments. I was just being stubborn and was a little ticked. I was trying to come in hot but was frustrated by inconsistent pedal travel, mushiness, inability to modulate properly and therefore all over on my entries. My g-g plots on turn entry were terrible. If the new brakes don’t fix it, I will definitely modify my braking style.

I couldn’t agree more that turn entry is where it’s at, especially the faster the turn. I work very hard on that (and yet – still suck).

On the R compound, my thought was to continue to beat on street tires until I was very consistent and then change to R’s because so many people say R’s are much less forgiving. Since I’ve never done it, I don’t know. From the video and data, do you think I’m ready?

DJ

Good decision.



Yes, driving a 911 is different from driving most other cars, and while there might be slight differences, the line is pretty much The Line.



It would seem to be not only easier, but also cheaper to try modifying your braking style, but it doesn't surprise me that you would rather spend money and attempt to throw technology at a problem instead of recognizing that your style is wrong, and fixing the problem by changing your style.


I have had professional drivers explain to me that the order of priority should always be: 1) Drive the correct line, 2) Maximize exit speed, 3) Maximize entry speed. From that, it would appear that you're going about this all backward. Your lines are fairly inconsistant and misshapen, which is killing your exit speed, and yet you're concentrating on entry speed?

Not yet, Grasshoppa... not until you can ****** the pebbles from my hand.


No. Get consistant first.