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Captain Thread Killer returns
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Discussion Starter #1
Last night I killed a rice car and floored the goat from a stop it rev'd way up and as I was taking off I heard and felt a weird noise I look at the tach and the needle was clearly in the middle of red somewhere between 6k and 7k.
I was worried maybe something happened in the engine because for whatever reason it never shifted down and went all the way up through the redline. I have read on here about the rev limiter and people bouncing off of it, but I don't understand what that means. When you do that does it make a noise in the engine? The goat felt like it still had all its balls later in the night...... Hopefully I did not do any damage. :(
 

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GTOholic
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The "rev limiter" shuts off fuel to the engine at 6200 RPM. It restores fuel flow at 6190 RPM, at least in my PCM. (I've looked at the settings with HP Tuner.) Your results may vary, meaning your settings may be different, but I doubt it.

Anyway, I've bumped that rev limiter several times and I really wish I hadn't. Over revving the engine can do serious damage, especially to the valve train. See the threads about "bent valves". I am not about to change my rev limiter setting. I want all the protection I can get.

From your description, I assume you drive an A4. I don't know how the automatic transmission responds to throttle input, but I would guess "flooring it" from a dead stop would tell the A4's PCM "this guy wants to GO" and it would delay shifting. If your tach was "somewhere between 6k and 7k", you should have hit the rev limiter. If you had, you'd know it. The engine quits momentarily. It is an important reminder to BACK OFF.

I think the dealership has the tools and know how to evaluate your engine's performance and tell you if any damage has been done. Also watch for oil consumption. If your car starts using oil, get it to the dealership right away. I probably would not tell them, "Hey, I've been hitting the rev limiter. Did I hurt the engine?" I would just ask them to do a compression check because you think the car has lost some power. Then again, they can probably read your PCM and see that the rev limiter has been bumped. Don't quote me on that, but I wouldn't be surprised.

Sorry for the long winded response, but this is a subject I've been considering closely. My car has lost a lot of low end torque and I have no choice but to take it to the dealership for evaluation. The prospect makes me nervous because I am sure they are going to proclaim, "VEHICLE ABUSE!"
 

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Captain Thread Killer returns
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Discussion Starter #3
FLORIT said:
Sorry for the long winded response, but this is a subject I've been considering closely. My car has lost a lot of low end torque and I have no choice but to take it to the dealership for evaluation. The prospect makes me nervous because I am sure they are going to proclaim, "VEHICLE ABUSE!"
Thanks Florit, that was a good response......I was worried because that had never happened before, even when I went to the strip. I thought instantly about the valves after reading all about your problems. It happened so quick I could not explain the noise really. I will watch it closely and go to the dealer if need be. They have got to expect this car to be pushed every so often. :D
Good luck with all your "issues" hope you can get it back to normal.
 

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13 year owner
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FYI, While there are a number of valvetrain issues with overrevved LS1's, it's generally on motors that are wound up well past 6,200rpm or misshifted resulting in a sudden "flash" of rpm's that blow past the rev limiter before the PCM can react.

GM sets it a little conservatively at 6,250 on purpose. Bouncing off of it will kill your power, but is actually the safety net keeping you FROM damaging your valvetrain. That's why it's there.
 

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Captain Thread Killer returns
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Discussion Starter #5
CMNTMXR57 said:
FYI, While there are a number of valvetrain issues with overrevved LS1's, it's generally on motors that are wound up well past 6,200rpm or misshifted resulting in a sudden "flash" of rpm's that blow past the rev limiter before the PCM can react.

GM sets it a little conservatively at 6,250 on purpose. Bouncing off of it will kill your power, but is actually the safety net keeping you FROM damaging your valvetrain. That's why it's there.
Thanks CMNT, does it actually make a noise in the engine when it happens?
 

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13 year owner
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If the valve is not seating properly against it's seat in the head, you would most likely hear a tapping or multiple tapping (if more than one cylinder is affected).
 

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This thing don't need no Hemi
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Rev Limiter Works!

Had a female ricer run a red turning right in front of me as I was hanging in the middle of the intersection on the end of the yellow to red turning left. The light went red, I go, and she runs the red without even slowing, nearly clipping the goats nose! Anyway, I blow the horn and she gives me an extended flip off. Well, that steamed the goat and we just had to do a blow by. It's amazing how the GTO just winds up like it will never end in 1st gear. I'm passing in first and just going for second when the engine cut out. Glad to hear that it was the RPM limiter shutting me down.

Never had time to look at the tach. I need that Red Line light and buzzer enabled - is that something I can do myself at home?

Yea, I'll do a forum search.

Aloha
 

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Might wanna knock first...
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whoa...where did you find this thread??? :eek:

Chris (GTPrix) can activate it, but you have to send him your cluster. Search should explain the rest.
 

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I love my Goat!
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WHen EastSide Performance did my tune, they put the rev limiter up to 6600 rpms, they say the stock LS1 can handle it without issue. They specialize in LS1s, and have a 6-sec camaro, so I think they know what they are talking about.

I've run up to 6500 rpms several times :driving: :burnout: without problems
 

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13 year owner
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HawaiianGoat said:
Had a female ricer run a red turning right in front of me as I was hanging in the middle of the intersection on the end of the yellow to red turning left. The light went red, I go, and she runs the red without even slowing, nearly clipping the goats nose! Anyway, I blow the horn and she gives me an extended flip off. Well, that steamed the goat and we just had to do a blow by. It's amazing how the GTO just winds up like it will never end in 1st gear. I'm passing in first and just going for second when the engine cut out. Glad to hear that it was the RPM limiter shutting me down.

Never had time to look at the tach. I need that Red Line light and buzzer enabled - is that something I can do myself at home?

Yea, I'll do a forum search.

Aloha
An ancient chinese secret when racing....one eye tach, one eye track!
 

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Captain Thread Killer returns
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Discussion Starter #12
back when I was newb
 

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WOT's Up Doc?
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I've hit the limiter a couple of times in my M6. I don't know about a "noise", the engine just sputters.

While I don't like hitting it, I'm not too worried when I do. That's what it's there for. I'm more pissed that I'm a crappy driver and hit the limiter again!

:burnout:
 

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The Entenmann's Shim-Sham
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12,247 Posts
I've hit the rev limiter before in my Strat. It happened more frequently when I just bought it and was learning the shift points.

Now it hasn't happened in a long time, but last time it happened I was turning onto a highway in second gear and started gunning it while watching the traffic for an opening. The engine started cutting and I was like WTF for a minute then realized I hit the rev limiter. Felt like a jackass for a minute and then shifted into third and carried on the rest of my day.
 

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that's right,I'm runnin' 11's
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GotTogO said:
I've hit the limiter a couple of times in my M6. I don't know about a "noise", the engine just sputters.

While I don't like hitting it, I'm not too worried when I do. That's what it's there for. I'm more pissed that I'm a crappy driver and hit the limiter again!

:burnout:

same for me
 

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This thing don't need no Hemi
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99 Posts
CMNTMXR57 said:
An ancient chinese secret when racing....one eye tach, one eye track!
Good one!

Just need that third eye I guess...
 
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