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Discussion Starter · #1 ·
Here are some interesting data for those following the real drag performance of Z06s with minimal mods. Mine has a Halltech Tric and the rest is stock. The car has been running consistent low 12.5s this summer in mixed weather.

Friday night at Capitol Raceway in Crofton, MD weather was in the low 80s; barometer was 29.85. Humidity was in the low 70%.

Made five passes in the following sequence with these results:

12.53 @ 115.8 with a 2.06 60'
12.35 @ 114.4 with a 1.94 60'
12.44 @ 115.6 with a 1.99 60'
12.49 @ 114.0 with a 2.03 60'
12.48 @ 114.8 with a 2.05 60'

Here is an extract of the slip for the best run.

RT: .5291
60': 1.9407
330': 5.2801
660': 8.0312
1000': 10.3681
1320': 12.3540
Trap: 114.3519

The five runs were very consistent.

My times from 60' to 1000' varied by only .050 seconds.

Times from 1000' to 1320' varied by only .012 seconds.

This reinforces what many others have said. All other things being equal, the key to ETs is in the first 60'. Said another way, I can't drop the ET much more unless I can bring the 60' times down, unless I add mods.

Car was dynoed at Carlisle on Saturday at 13,800 miles and made about the same numbers it produced at 7000 miles. Some folks have said the car will produce more power as it accumulates miles. This does not appear to be the case on my car.

I'll be interested to if the cooler weather this fall has an impact on my ETs. I'll let you know.

Best to all,

Ranger
 
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SMOKIN

Congratulations! Too bad GM doesn't factory install the TRIC. That kind of e.t. is right there with the Viper (old)

Do you power shift or speed shift?

An article on this site that I posted last night showed the stock 02 walking away from the Porsche TT. The GM selected driver actually shifts WITHOUT the clutch like he was driving an F1 car!

I'm afraid to try this. I used to do it all the time on my motorcycle, but this is a little differenct.

Anyone tried this?

Jim
 

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Well once again I interject and I don't even have my car yet. Delivery date of 9-20-01 changed to 9-19-01.

I have shifted without the clutch many times on my '96 Z-28. The tranny sure doesn't like it though. Makes a small grinding noise each time, but this T-56 is beat to shit in all reality. I have at least 750-1000 passes on it and only about 40,000 miles. Many launches at 5,500-6,000 rpm and launching on ET Drags and N2O. 1.6 short times. Road Racing, auto-xing, daily driving, etc, etc. The tranny is actually being rebuilt now, because everytime I shift into 2nd it grinds. It pops out of some gears, I can't powershift because when I slam (and I do mean slam) it into 3d gear it goes up between 3d and 5th and my reverse lights come on and it acts like it is in neutral.

I guess that I shift fast enough with normal spirited shifting though. I can shift normally, taking foot off the gas, stepping on the clutch, shifting, releasing the clutch and stepping back on the gas just as fast as I can when not taking my foot off the gas. And when I don't use the clutch the same scenario. But both speed shifting (leaving foot on the gas) and power shifting (clutchless shifting) sure impress the passengers in the car!!! :)

I've got enough 1/4 mile runs to know what I and my car ('96 Z-28) are capable of and found that I don't need to powershift or clutchless shift. It is just harder on the car :/
 

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You don't know how lucky you are to be at a low altitude (high barometer).

Good runs!
 
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Clutchless

Tried it today, but at about 4000 rpm. Right after you begin to let off the throttle, you shift and it goes into the next gear without a crunch or grind.

It does have some resistance, so my feeling is forget it.

Unless I have free tranny's in the wing, I think I'll stick with the clutch.

John Heinrcy made it happen on the 02, and it surprised even Car and Driver.

:eek:

Jim
 

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Discussion Starter · #18 · (Edited)
In response to an email, I'm posting the launch procedure I'm following. Not claiming it's the best one.

Here's what I'm doing.

Stage: Windows up. COMPETITION DRIVING set. Radio off. AC off. I pull straight through the water. At Capitol they won't let you go around it.

I spin the stock F1SC tires for a second or two to clean them off. I was running 23 lbs in the rear and 42 lbs up front. I shallow staged, barely tripping the second set of bulbs.

Launch: The track was not prepped with VHT that night so I was holding just 2200-2400 rpm and quickly releasing the clutch with full engagement occurring in the first 2'-10'. I let the tires hook before going to WOT.

Shifting: I'm running the stock shifter. Did some slight throttle lift on the shifts particularly on the 1st-2d where it's easy to spin a lot. Was shifting 1st-2d and 2d-3d at an indicated 6300, because it revs so fast and I want to stay off the limiter. The 3d-4th shift was at an indicated 6500.

Two other things. My first night at the drags wearing running shoes instead of low-cut work boots. I'm thinking the thinner soles give me a little better feel for what the rear wheels are doing. Finally, I'm using the AC in recirc mode to fire up both fans before I enter the final staging area. I find this brings the H2O temp down to 194 just fine.

Ranger
 
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QuoteFinally, I'm using the AC in recirc mode to fire up both fans before I enter the final staging area. I find this brings the H2O temp down to 194 just fine.

This is one of our dyno secrets. Without a coolant bypass on all of our dyno pulls, we let the car sit for 10 minutes between each pull, then run the car in neutral for a few seconds with the AC on, until the water temp resets to 199 to 205....then the dyno pull.

On the 2002, if you forget to cool it down, it loses 5 to 6 HP! This is why we did so many pulls. Traditionally the C5 make progressively more power after each pull. I disputed this with the guy at PowerTrain Dynamics today, and he was convinced after he saw it with his own eyes.

This is another reason for the TBCB. The throttle body gets up to 230+ degrees. It heats up the manifold, airbridge, IAT sensor and ulitmately produces more heated air into the manifold. Result is -1% of your horsepower for every +10 degrees you heat the air.

The TRIC has a distinct advantage over other systems at the track due to this factor. It also pulls extremely hard right to redline.
 

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"I pull straight through the water. At Capitol they won't let you go around it."


WTF!?!?!?! I'll NEVER understand why a track won't allow folks to drive around the water box, especially with street tires. We all go apeshit when the ricers all drive through the water and ruin the track out here at Sacramento Raceway.

You'd figure that folks getting water on their tires (even if you burn off the rear tires the fronts still have some water on them) might not realize it and get a bit out of control and maybe hit the wall!!! Now I know you have to sign a waiver to race, but most any lawyer could get around that. Just looks like a problem waiting to happen.
 
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