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Discussion Starter #1
I was tempted to drive to SA and watch the Viper vs. Vette show, but instead decided to go to HRP and flog my '02 and do some much needed testing.

I managed to get in 5 passes in 2 hours. The car at this point is bone stock down to the stock paper air filter. I had intended to have a light load of fuel, but instead ended up having a full tank of gas.

My first pass was at around 7pm and the last was at 9:15. Temperatures ranged from 82 down to 78 and the humidity was high +90% (In short, the air sucked). I really was more concerend with working on my 60' times rather than quarter mile times, as I knew the car would probably drop off from the last time I ran it. I also intended to play with shift points, etc... and see what did and didn't work.

My first pass ever in the car a few weeks ago was leaving just off idle and resulted in a 2.15 60' time and a [email protected] the air was cooler and the humidity was lower, hence the higher trap speed.

Best pass last night was a 2.041 60' time [email protected]

Most everyone I talked with complained about the air quality, and how slow their cars were running. I raced a supercharged 93 mustang who beat me by two car lengths. He went an 11.88 @114 and complained because his trap speeds are sometimes as high as 121. I think he was ready to burn his car. He pulled me over and asked what my time was. I think he was mad because our race was so close, and he didn't pull on me on the big end. The he spotted the badges on the side of the car and went "OH, so thats a Z06, not just a regular 'vette" then he didn't feel so bad and put the can of gasoline and the ligher away and went to go get back int he staging lanes. I was playing with shift points on that pass and only went a 12.95 @110. Since he only beat me by 2 car lengths, I can only imagine how he would have felt on the next pass when the car went a 12.667 which would have put me one length in front of him. (I hate seeing mustang owners cry....) :)

Anyhow, a couple of observations. I am still working on getting a feel for the clutch. Best results so far have been to leave around 2000 rpm, slip the clutch and roll into the throttle. I am easing into the clutch too fast at this point and bogging the car on the leave slightly. I feel if I can control the release better, I can drop the 60' times significantly.

Leaving between 2500 and 3000 on the stock radials tends to lead to too much wheelspin for me.

If you are going to run your car at the drags shut off Active handling completely. I had mine in Performance mode. While doing my burnout the car moved a little sideways and the active handling kicked in ( I guess it thought I was in a slide) and shut down my burnout.

I played with the shift points and this is what I was able to determine.

Hitting the rev limiter at all seems cost about .1 seconds in a pass. So if you hit the limiter at all figure it costs you about this much. If you hit it in both the 1-2 and the 2-3 figure .2

Short shifting the car is quite detrimental to quater mile times. I played with a couple of different shift points and found that it seems to run best if you stretch them out right to the limit, but not past.

Third gear seems to be the killer. The car really seems to pull best in this gear. On one pass I short shifted third gear to fourth at about 5000. The car dropped to [email protected] I tried 5500 and the car went a [email protected] So, my advice in this department is to watch the tach in 3rd gear. The car seems to hang a bit at the top of 3rd, but hold 3rd as long as you can it is woth some E.T. I went all the way to 6000 on the 3-4 and the car went a [email protected]

I ran these passes with minimal cooldown and in bad weather to see how it should fare on the street. It appears to me that currently the only real problem in the car so far is with its drivers inability to 60'. So, I think I am going to borrow at set of 16" E.T. Streets for the next go around and see what the car can do if traction is not an issue.
 

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Good report on your experience. Thanks.

Some comments.

Short shifting definitely hurts ETs. I shift to 2d and 3d at an indicated 6200-6300 because I want to stay off the limiter with the revs coming so fast. I agree that running 3d right to 6500 is best, as is making a strong, fast shift to 4th.

I've learned that 60' times below 2.0 will occur consistently ONLY on tracks that are well prepped and sticky. It's hard to break below the low 12.4Xs on an 2001 Z06 unless the 60' is below 2.00.

The track conditions will dictate launch rpm. I do anywhere from 1800-3200 depending.

Here are a couple good threads to check, in the event you missed them:

http://forums.corvetteforum.com/zerothread?id=170174

http://forums.corvetteforum.com/zerothread?id=169734

Both Power Shifter and I posted some info that will be of interest.

Ranger
 

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J-Rod and Ranger

Thanks for the comments!
 

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J Rod.......

You said turn OFF AH altogether..........well, unless I am mistaken, when in COMP MODE, the TRACTION control is OFF......and the AH stays on.........
This will keep your rear end out of the walls........
Turn off AH, and TC, and you are axing for it.......:eek:
 

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Running COMPETITION DRIVING Mode at the Drags

I agree with ZO6LS6.

Running at the drags in COMPETITION DRIVING mode will limit the worst that can happen if your rear end gets seriously out of line. It won't adversely affect for ET, unless control of the car becomes an issue. If that happens your ET will be the last thing on your mind.

Ranger
 

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Discussion Starter #6
No, thats exactly what I was talking about. I had my car in competition mode. When I went to pull my burn out the car moved a little sideways as I was rolling forward and the car got all goofy (pulled throttle, hit brakes, etc...). So, I just decided to leave AH of completely so that it doesn't happen again. I did, and no more problems.

As for running without it, I have been drag racing, street racing, you name it for many years now. More than one of the cars that I have driven was an old slapper bar cars with whooped out suspension (so they transfer) on slicks with say 10 lbs of air in them, and drum brakes. Trust me when I say, the Corvette is like driving a Cadillac down the strip. And trust me, I know when to lift during a pass.

The first pass I made in the car was in competition mode, and I had no problem. Just when the car moved sideways during my burnout in a later pass. I am going to check the next time I go and ensure that this wasn't simply driver error, and that I didn't throw the car back into AH by mistake somehow.
 

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AH activation at the drags

I ran the car at a terrible local track as part of our club's annual day at the drags. Worst traction of the four tracks I've run on, by far; actually dangerously poor traction.

My AH tripped numerous times on shifts to 2d, 3d and 4th. Very narrow lanes too. Glad I was in COMETITION DRIVING.

I appreciate that some drivers have the experience to refrain from using the technology that the rest of us depend on to limit the worst that could happen. For myself, I am racing my daily driver. Might feel different if it were a single purpose race car. But I doubt it.

Ranger
 

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Discussion Starter #8
Ranger,


I do appreciate what you are saying. As I said, I am going to check again and make sure that I hadn't tripped the car back into full AH rather than competition mode.

It is possible for instance that I had shut the car off one last time before I staged the car and so it had defaulted back to full AH mode. Like I said, I am going to check it.

As for Racetracks, I run at HRP. It is one of the big supertracks. The lanes are really wide, and even when the track isn't prepped so well (for them), it is better than some of the small tracks I have been to. An average street car like the Z06 isn't in too much danger in these conditions. About the only problem I have ever had is getting completely out of the groove in some of my other cars. At this point you just have to lift.

I learned my lesson many year ago when I watched a Texas Pro Stock racer by the name of Bill Staley get out of shape several times, not lift, and come over the wall in Dallas 20' in front of me. I then got to watch as his car cut itself in half on a light pole. And then I watched him die before they could cut him out of the car.

I learned my lesson during a street race one night when someone thought it would be really cool to pour water in my lane to better their odds. I only found out after the race. Since it was a money race I didn't back out and tried to pedal the car. When the slicks rolled under and the car pitched up on two wheels I decided I should probaly back out of it. I probably should have backed out a little sooner. This and a few other lessons taught me the value of "lift today live to race another day".

Am I against AH or Competiton mode. no.
Do I think they are bad. No.
Do I consider myself the best drag racer out there, no.

If I can use them to help me, then I will. But if they are going to hinder me I'm going to shut them off. And I don't begrudge anyone who want to do otherwise. I was simply stating my impressions and my opinions, wrong as they may be.

Like I said, I am going to go back and try again, and see if I just messed up and pu the car back in full AH mode before the pass in question.
 

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J-Rod,

Track/street mishaps always become deeply imbedded in our memories.

Wish there were an indicator on the dash to reflect that the car is in COMPETITION DRIVING, similar to the icon that shows that TC is OFF.

Would provide a quick visual check on AH status when the DIC is set to monitor water or oil temp or the like.

Ranger
 
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