ESPN's Ray Evernham answers your questions

Gillett Evernham Motorsports co-owner Ray Evernham shared his expertise with NASCAR Icons by answering some questions from readers.

Updated: July 29, 2008, 2:24 AM ET
ESPN.com

NASCAR Icons readers filled the mailbag with questions for ESPN analyst Ray Evernham and he responded to some of the best ones below.

Ray Evernham
David Griffin/NASCAR SceneRay Evernham likens a crew chief's duties to that of a doctor trying to come up with an appropriate diagnosis.
Evernham, who is co-owner of Gillett Evernham Motorsports, started out racing modifieds before making his name as a crew chief. He won three NASCAR Cup championships and 47 races with Jeff Gordon and Hendrick Motorsports in the 1990s before venturing into ownership in 2000.

Kasey Kahne, Patrick Carpentier and Elliott Sadler drive Dodges for Gillett Evernham in the Sprint Cup series this season.

Here are your questions and Evernham's answers:

Because you knew during the Indianapolis race there would be only 10 laps of green between cautions, did you reduce the amount of fuel you put in the car at each stop?
Chris,
Indianapolis

Evernham:
That's a very, very good question by, obviously, a very astute fan. But, yes, you want to make the cars as light as you can. So the crew chiefs who were being heads up and smart guys knew that the lighter they could make the car the better it would be on tire wear. So the good crew chiefs were only putting in as much fuel as they needed. And that only meant about every 12 laps we were going to have a caution.

When did the cars first have rev limiters in them? I was wondering if the addition of electronic rev limiters has simplified driving by taking throttle control out of the equation for the most part. What would happen if there were no limiters and drivers had to be more careful with the throttle so as not to blow the engine?
Rich,
Centerville, Pa.

Evernham:
Boy, I can't remember when the first rev limiter was invented, but I know there were mechanical-type rev limiters in cars in the early '70s, actually. So as far as the electronic rev limiter, there's a company called MSD that has been very instrumental in developing those things and I can remember in the '80s cars having rev limiters. But I think the first rev limiters were actually mechanical rev limiters used in the '70s.

Right now the rev limiter is really, basically there for a safety over-rev if you were to miss a shift or if you were to have a drive line failure. The drivers do a pretty good job of knowing where to shift on the engine power curve.

So we basically use the rev limiter for two reasons: As a safety if there is a missed shift. Or sometimes it's just a little warning; you'll set a rev limiter for a driver who has a tendency to overdrive into the corner and when he hits the rev limiter he'll know that he's at an RPM range where he needs to start letting off because it is very easy to overdrive these cars sometimes.

With all the ways to change the handling of a car [air pressure, tape, wedge, etc.], how does the crew chief decide which to adjust?
Don Good,
Johnson City, Tenn.

Evernham:
It's really like a doctor. You look at all of the things, the diagnosis, to figure out how you should treat the patient. It's really depending on what the driver is saying and what your tire pressures, the tire temperatures are doing.

It sometimes is a combination of all of those things, not just a simple adjustment of either wedge or tire pressure or track bar. Sometimes it's a combination of all of those things but a large part of it comes from what the driver is telling you, which is again another reason why driver and crew chief communication is so important.

I have heard it mentioned on several NASCAR broadcasts that these guys are configuring their front-end geometry so when the car dives under braking it rolls to the left and not the right therefore keeping the front valance level through the center of the corner. How are they doing this?
Will Blocksome,
Auburn, Ala.

Evernham: In front-end geometry there are tons of points and intersections and things that you just can't see and those lines and pivot points are created by the angle of the upper and lower control arms. So largely what is being done is changing the angle and the height and the reference of the angle and height from lower and upper control arm from right side to left side.

Basically, if you look at the cars now you'll see the mounting points for the A frames at a lot different angles and a lot different heights, especially from front to rear. When you change the angle of the A arms from front to rear in just a planed view it changes the reaction of the car under braking and acceleration.

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