Terrible 1/4 times..Why???
 

Very Disappointing 1/4 mile times so far. I bought this 2006 ZO6 back in March after driving one a couple of years ago. I love this car, but seeing the fast list with cars on street tires going 1.6 1.7 to 60ft trap speeds of 125 to 128 ALL stock (record 10.96 et). Either my car is a dog or these others are ???. I have Killer bee intake, Billy Boat exhaust, and a tune. I dyno'd the car at 497hp 466tq. 2 times to the track 5 passes with nitto nt05 tires best 60ft 2.0 121 mph et 12.07. Factory claims 11.7. I dropped tire pressure from 25 to 20 to 18. tried letting the clutch out at 3000 2800 2500 2000 (bit and bogged went 2.11 to 60). Huge long burnout in 2nd gear last pass went 2.0 to 60 let clutch out at 2500. Wanted a 10 second street car seems unrealistic at this point. I will get some 17" rims and some hoosier or mt tires. I think the nittos suck. The MPH is not where it should be either. Looking for advice..

Practice...practice..practice.....

Ranger has some write ups on all his runs and what he did to get there (I think)

Read, and join, this current thread/discussion :thumbs:

http://forums.corvetteforum.com/c6-z...ft-points.html

Thanks just did.

The 60' times are a bitch with the Z's, and half of 2nd gear isn't much better. I'm with you....I have never got a 60' less than 2 seconds, but I have turned in the 11's. You have to watch the short shifting. They sound like they are ready for the next gear, but when you look at the tach.....you still have a ways to go.

Larry

What elevation are you running at?

Jay

You also need to take into consideration the track and weather conditions. Building a 10 second street car isn't as easy as it sounds, especially one with a manual transmission. Believe me, I've tried, and I can't drive like Ranger, but it took me ~560rwhp on street tires (Nitto Invos), excellent track prep and a near flawless launch to finally break into the 10s (10.90 @ ~130MPH). Best I could get with ~500rwhp was mid 11s. I haven't been back to the track with the car as it sits today (slightly milder cam that gave up a little on the top end but gained some torque on the bottom), although I suspect it would do consistent high 10s with some drag radials.

EDIT: Side note, my last time at the track I was getting horrible wheel hop and nothing I did could stop it from happening. It never did that before. Not sure why it started happening all of a sudden. I've since put the DRM Bilsteins on the car. Hopefully that helps.

http://forums.corvetteforum.com/c6-z...and-cures.html

:iagree:
The time I went to the track I had all kinds of traction problems in 1st and 2nd on Invo's. High 11's with horrible 60', Pulls hard in 3rd to a 130 mph trap.

I didn't lower air pressure or adjust my coilover suspension though.

I need some practice and better tires.

This is very important. High elevation kills MPH in a big way. Specially on NA cars and your MPH does seem a little low.

make sure you take all three gears to 7000rpm and shift into 4th before the traps.If you dont go through in 4th you wont get a high mph.

For sure. Elevation for MO is 604 ft.

Taking them all to 7K will surely hit the rev limiter. To improve traps start your shift at about 6700-6800.

:iagree: taking them to 7k is a guaranteed way of hitting the rev limiter.

As soon as you depress the clutch for your shift when you see 7k, or even before then you'll hit the rev limiter, as there is some tachometer lag, and what you see indicated on your tach, is actuall a few hundred rpm of where you are.

also, DA around this time of year, depending on where you are, is not going to allow for any stellar times.

The idea now is to get your launch and shift points down for when the weather and conditions are good.

I wouldn't worry too much about the times now.

Rev limiter is actually 7200 RPM. I always shift around 6900-7000 and have never once hit the limiter. The shift arrow in the HUD doesn't come on until you're close to 7K RPM.

If your shifting at 7K you are most likely hitting the rev limiter and dont even know it since you are off the throttle.

I dont know if you track your car or not but for me taking the rev's to 7K would lower my trap by almost 2mph. As soon as I started my shifts earlier they came right up.

:iagree: Yes sir. :rock:

St Louis elevation is 535 ft. The Nitto NT05's are better than the InVO's I thought.I know now that hammering the throttle and coming too fast off the clutch hurt my 60ft times now. Hard not to do that. It's my first time racing with a 6speed Automatics are EASY. No comparison. Also had the car in Competitive Driving mode.
In a C6 Corvette you want to be in Traction System Off mode.
Not sure what difference that would have made.

propain, how tall of a guy are you?

Is your seat position the same for street driving as it is for on track driving?

Just over 6 feet. My seat position is much closer when I am on the road course.


Ahh street driving.. sorry... my seat if further back when on the track. I like to just be able to fully press the clutch in. Makes it easier for me to shift quickly.

Post the slip bud. It will help us get a better understanding of what your dealing with.