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I have a 2005 (LS2) with a manual transmission and Z51 track package. I have installed a Vararam CAI and Flow Master Mufflers. That's it ... no other bolt-ons or internal work. Stock. 40K miles.

I do not drag race. But I do track the car on road courses like VIR.

Now the questions.

1) What is the stock rev limit for my car? 6500? 6400? I have heard it is different for C6s with auto transmissions (6700?)? I have also heard that it also varies by manual gear selection (ie lower for 5th and 6th)? Does someone have the FACTS?

2) How many more RPMs could I increase this limit without serious risk of engine problems?

One of the reasons that I am asking is because I am hitting the rev limiter in 4th gear at about 150 MPH in a spot where I am just about into my brake zone at a couple of tracks. Yes, I can short-shift to fifth gear to try and increase terminal speed, but the time it takes me to do that negates the benefit. So I think a few hundred more RPM is the answer.

Thanks for your replies...
 

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6500 is redline. Fuel cutoff is 6600 (Based upon LS3)

I would not go above 6700 on the stock valve train, but even then you need to modify the ECM to allow for that rpm assuming the LS2 keeps the same fuel cutoff as the LS3
 

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Discussion Starter #3
6500 is redline. Fuel cutoff is 6600 (Based upon LS3)

I would not go above 6700 on the stock valve train, but even then you need to modify the ECM to allow for that rpm assuming the LS2 keeps the same fuel cutoff as the LS3
Thanks for the reply, Ragtop. I'm not sure that the LS2 and LS3 have the same stats. I am looking to get a performance tune and want some solid facts about the LS2 before I talk to the tuner. Hopefully a LS2 expert can chime in here as well...
 

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The problem isn't the RPM, it's your gearing. For this particular track you either have to short shift or change to a shorter numerical gear.

Turning the motor higher isn't going to net you anything. The HP peak for a stock LS2 is around 58-5900 RPM, so twisting it higher is actually giving you diminishing returns.

By 6500 you have dropped about 25 -40 HP from 6K.

Change the cam or gears if this is the track that you spend most of your time on.
 

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6500 is redline. Fuel cutoff is 6600 (Based upon LS3)

I would not go above 6700 on the stock valve train, but even then you need to modify the ECM to allow for that rpm assuming the LS2 keeps the same fuel cutoff as the LS3
I didn't know there was a fuel cut off when redline is hit. Never got that close to news to me
 

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I didn't know there was a fuel cut off when redline is hit. Never got that close to news to me
Gotta love people who baby their cars :lol:

35 seconds into this video, when I do a burnout; that's what the fuel cut rev limiter sounds like:

 

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Gotta love people who baby their cars :lol:
I generally learn where fuel cut-off is every time I do a new major mod. Install headers, boom first time out right off the limiter. Install gears, first time I try to run it to redline, boom, bounce off the limiter. :lol:
 

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I generally learn where fuel cut-off is every time I do a new major mod. Install headers, boom first time out right off the limiter. Install gears, first time I try to run it to redline, boom, bounce off the limiter. :lol:
And that's how its done! :lol:...
My best rev limiter moment ever was in Utah, crossing the desert in my newly purchased C5 Z06... I had just graduated in Michigan, got a job in Los Angeles, and bough the car on Ebay when it was located in Talahasse, Fl. I flew down, picked it up and started driving. Fl - NY - IL - CO - CA.
I was in Utah on day 4, coming down a big, empty, perfectly straight stretch of road, cruise control set at 130MPH. I dropped it into 5th and held it to the floor to a HUD-indicated 179MPH. At that point the car slowly started bouncing the rev limiter in 5th gear... It had nothing more to give... It was epic!

The car:


The road:


The older gentlemen who sold me that Z06 paid $56,000 for it new back in 2003. I bought it 4 years and 12,500 miles later for $29,000... He essentially lost 27 thousand dollars to keep it in a heated garage, wax it and take it out on the weekends to parade it around town at the speed limit when the weather was nice to the tune of 6K miles a year.
You better believe when I sold that car less than a year and almost 20K miles, a fresh set of tires later, and for more than what I paid for it, I had gotten my money's worth from it :sm_party:
Oh yeah, ZERO mechanical issues too... These things are made to be driven hard, as long as you're not an idiot about it :lol:
 

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I have a 2005 (LS2) with a manual transmission and Z51 track package. I have installed a Vararam CAI and Flow Master Mufflers. That's it ... no other bolt-ons or internal work. Stock. 40K miles.

I do not drag race. But I do track the car on road courses like VIR.

Now the questions.

1) What is the stock rev limit for my car? 6500? 6400? I have heard it is different for C6s with auto transmissions (6700?)? I have also heard that it also varies by manual gear selection (ie lower for 5th and 6th)? Does someone have the FACTS?

2) How many more RPMs could I increase this limit without serious risk of engine problems?

One of the reasons that I am asking is because I am hitting the rev limiter in 4th gear at about 150 MPH in a spot where I am just about into my brake zone at a couple of tracks. Yes, I can short-shift to fifth gear to try and increase terminal speed, but the time it takes me to do that negates the benefit. So I think a few hundred more RPM is the answer.

Thanks for your replies...
I think the easiest way out of this and the cheapest is to get a slightly taller tire. That way you won't be over-revving the motor into the turn. Do you track the car with different tires?:toocrazy:
 

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I think the easiest way out of this and the cheapest is to get a slightly taller tire. That way you won't be over-revving the motor into the turn. Do you track the car with different tires?:toocrazy:
The catch with that is that the traction control, engine deceleration control and active handling system will see that tire spinning slower and think the vehicle is sliding; they will then start to behave in all kinds of very unpredictable ways.
The taller tire trick was great back in the middle ages of cable actuated throttles and no electronic gizmos, but most cars today will not work with tires that have a different overall diameter from what was manufacturer specified...
 

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The catch with that is that the traction control, engine deceleration control and active handling system will see that tire spinning slower and think the vehicle is sliding; they will then start to behave in all kinds of very unpredictable ways.
The taller tire trick was great back in the middle ages of cable actuated throttles and no electronic gizmos, but most cars today will not work with tires that have a different overall diameter from what was manufacturer specified...
Yes that would be a problem. What about increasing tire height on all four tires? A little expensive though. Perhaps an axle ratio change may be best
 

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Discussion Starter #12
So far, I am tracking with the same tires that I use on the street. Nitto Innvo tires in stock sizes. Good balance between streetability with rain and track performance.

Nice array of suggestions provided so far, but since I am having the car tuned, it would be cheapest/easiest to just bump the rev limiter fuel cut-off by maybe 200 RPM. I get the fact that those RPM levels are on the down side of the torque and HP curves, but it would elongate my acceloration zone just a bit on the long straights.

Has anyone done this with stock internals without issues?
 

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So far, I am tracking with the same tires that I use on the street. Nitto Innvo tires in stock sizes. Good balance between streetability with rain and track performance.

Nice array of suggestions provided so far, but since I am having the car tuned, it would be cheapest/easiest to just bump the rev limiter fuel cut-off by maybe 200 RPM. I get the fact that those RPM levels are on the down side of the torque and HP curves, but it would elongate my acceloration zone just a bit on the long straights.

Has anyone done this with stock internals without issues?
Yeah, a 200RPM jump is fairly common. Don't stay there long on stock springs though ;)
I believe mine redlined at 6800 with the blower; stock engine otherwise.
 
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