fuggles
08-22-2015, 10:47 PM
Friday 8/21/2015
Track configuration 3 mile east with bypass CCW
Northern California Racing Club
2009 ACR hardcore, stock +A/C & Radio
mild track alignment approximate numbers:
camber 1.8F/1.5R
slight toe out front
slight toe in rear
shocks 6 clicks from firm c/r
approximately 1 inch lower than stock
original michelin pilot sport cups with 3K miles
track splitter
stock rear wing position
2% wedge @ 3357#
plus 10 lbs of bug carcasses from the drive up the night before
It was a beautiful day in Willows, CA. Cool in the morning sessions around 70F. Mid to high 80's in the afternoon. And WOW can this car perform! The amount of grip the car has is staggering. It reminded me a lot of the karts I used to run.
I've driven karts on a few of the tracks in northern California, but this was my first track day in a car. I found there to be many similarities between driving karts and cars on a track. Similarities such as finding the brake point, brake pressure, turn-in, being smooth, carrying speed, and holding yourself in your seat with the steering wheel in the turn. I also found a few significant differences. Like that third pedal. You mean to say I have to brake and downshift? Where is the downshift marker? What gear am I supposed to be in?
I was in the driving school group so the first couple sessions we were following an instructor around at grandma speed trying to find the line and learning how to point-by. In a viper with a 307 diff it's second gear and no shifting. In the last 3 sessions we were on our own driving as fast as we dare. It was at this point that I realized I have much to learn.
I went into this event with eyes wide open. I am not naive. I spent countless hours in a kart at 50 mph headed into a hairpin wondering if I would make it. But this is different. I can't see around the corner. Where is the flagman? When do I downshift? Heal-toe or just drop the clutch? By the way, I suck at heal-toe. Whew. So many decisions. I know. It was my first track day. I need to get comfortable with the car and learn the track. And I can't wait! What fun. I'm already planning the next event.
Speaking of planning, I'm thinking about some adjustments to the suspension and aero. Camber seemed pretty good. Very even heat across the tire. The track at thunderhill seems pretty smooth. It has elevation change but not many bumps and for the most part, berms are flat. However, the car felt like it was hopping and skidding over small bumps.
I have a couple questions for those more knowledgeable.
I'm thinking of softening the compression on the shocks. Good/bad/indifferent? If good, how soft? Is it normal to run compression softer than rebound as a general rule? What about the ratios for front to back? Stiffer in the back?
I'm also thinking of adding more wing. Thunderhill is pretty fast but the 6/7/8 corner slash backstretch may benefit from more wing. I don't know.
Thanks for reading, and I look forward to seeing more vipers at the track. What a blast.
Track configuration 3 mile east with bypass CCW
Northern California Racing Club
2009 ACR hardcore, stock +A/C & Radio
mild track alignment approximate numbers:
camber 1.8F/1.5R
slight toe out front
slight toe in rear
shocks 6 clicks from firm c/r
approximately 1 inch lower than stock
original michelin pilot sport cups with 3K miles
track splitter
stock rear wing position
2% wedge @ 3357#
plus 10 lbs of bug carcasses from the drive up the night before
It was a beautiful day in Willows, CA. Cool in the morning sessions around 70F. Mid to high 80's in the afternoon. And WOW can this car perform! The amount of grip the car has is staggering. It reminded me a lot of the karts I used to run.
I've driven karts on a few of the tracks in northern California, but this was my first track day in a car. I found there to be many similarities between driving karts and cars on a track. Similarities such as finding the brake point, brake pressure, turn-in, being smooth, carrying speed, and holding yourself in your seat with the steering wheel in the turn. I also found a few significant differences. Like that third pedal. You mean to say I have to brake and downshift? Where is the downshift marker? What gear am I supposed to be in?
I was in the driving school group so the first couple sessions we were following an instructor around at grandma speed trying to find the line and learning how to point-by. In a viper with a 307 diff it's second gear and no shifting. In the last 3 sessions we were on our own driving as fast as we dare. It was at this point that I realized I have much to learn.
I went into this event with eyes wide open. I am not naive. I spent countless hours in a kart at 50 mph headed into a hairpin wondering if I would make it. But this is different. I can't see around the corner. Where is the flagman? When do I downshift? Heal-toe or just drop the clutch? By the way, I suck at heal-toe. Whew. So many decisions. I know. It was my first track day. I need to get comfortable with the car and learn the track. And I can't wait! What fun. I'm already planning the next event.
Speaking of planning, I'm thinking about some adjustments to the suspension and aero. Camber seemed pretty good. Very even heat across the tire. The track at thunderhill seems pretty smooth. It has elevation change but not many bumps and for the most part, berms are flat. However, the car felt like it was hopping and skidding over small bumps.
I have a couple questions for those more knowledgeable.
I'm thinking of softening the compression on the shocks. Good/bad/indifferent? If good, how soft? Is it normal to run compression softer than rebound as a general rule? What about the ratios for front to back? Stiffer in the back?
I'm also thinking of adding more wing. Thunderhill is pretty fast but the 6/7/8 corner slash backstretch may benefit from more wing. I don't know.
Thanks for reading, and I look forward to seeing more vipers at the track. What a blast.