Rev limiter
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8th Gear
Joined: Apr 2018
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From: Antrim NH
Rev limiter
When I drive my 2016 Z51 in Sport or track mode and I rev up to redline it seem to be spending too much time in the rev limiter. The symptom reminds me when, in the 60's, you would float the valves. It doesn't do it in any of the other modes.
Le Mans Master
Joined: Dec 2000
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What do you mean "spending too much time in the rev limiter?"
And are you putting the foot feed to the floor and holding it just to see what happens?
If so, and in sport and track the electronics keep the RPM closer to red line, I expect this is intentional; the car assumes this is what you want when driving in the most aggressive modes.
And are you putting the foot feed to the floor and holding it just to see what happens?
If so, and in sport and track the electronics keep the RPM closer to red line, I expect this is intentional; the car assumes this is what you want when driving in the most aggressive modes.
Safety Car
Joined: Mar 2004
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From: South Florida
The Rev Limiter is nothing like a 60s car with an over revved valvetrain. If you actually hit the rev limiter in these cars the engine will fall flat on its face for a moment before resuming. Once of the most common things I do in tunes is to remove this type of rev limiter and make it more like the C5's where it doesn't lose a bunch of steam if you actually hit the rev limit.
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8th Gear
Joined: Apr 2018
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From: Antrim NH
Elk, thanks for the reply. It's an automatic so yes I keep my foot to the floor and expect it to shift up with no hesitation. As I said, it reminds me of valve float back in the 60's. The symptom is when it reaches the red line the RPMs go down and the car slows down noticeably and then shifts.
Le Mans Master
Joined: Dec 2000
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I think I understand. You instead want the engine to shift at or just prior to red line so there is minimal loss of forward momentum.
That is, it is not the rev limiter per se which is the issue, but rather the transmission shift points in Sport and Track.
That is, it is not the rev limiter per se which is the issue, but rather the transmission shift points in Sport and Track.
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8th Gear
Joined: Apr 2018
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From: Antrim NH
Elk, again, thanks for the reply. I have an appointment on the 11th. Will let you know what I find out on both problems.
Can I ask where you gained all of your knowledge?
BTW I had my Corvette battery maintainer on all winter and it had the two green lights on. After I read your first reply about a low battery I hooked it up again and the amber light came on indicating that the battery was charging. That was about 4 hours ago and it is still charging. Do you know if I have to disconnect the battery if I put a charger on it?
Can I ask where you gained all of your knowledge?
BTW I had my Corvette battery maintainer on all winter and it had the two green lights on. After I read your first reply about a low battery I hooked it up again and the amber light came on indicating that the battery was charging. That was about 4 hours ago and it is still charging. Do you know if I have to disconnect the battery if I put a charger on it?
Le Mans Master
Joined: Dec 2000
Posts: 5,348
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Unless the battery is deeply discharged it should charge back up just fine. It can take a good while.
It is also possible the battery is reaching the end of its useful life. These cars are exceedingly sensitive to low battery voltage. Thus, I suggest getting the batter load tested to make certain it is still in good shape.
It is also possible the battery is reaching the end of its useful life. These cars are exceedingly sensitive to low battery voltage. Thus, I suggest getting the batter load tested to make certain it is still in good shape.
Last edited by Elk; May 3, 2020 at 09:18 PM.
