biggrin

Driving home tonight I found myself on an open stretch of road. Went 90% throttle in 3rd then grabbed 4th. Unfortunately it wasn't 4th..ended up in 2nd instead. Car jerked and revs shot up. I immediately disengaged the clutch and saw the tach bounce off redline. Not sure if it went above redline. The car ran fine after this incident and idles smoothly but I'm shaking. :sad: Couple of questions:
1. Would the rev limiter kick in to prevent damage to the engine in this scenario?
2. Shouldn't the gearbox have prevented me from making an inappropriate shift?
3. If we do overrev, what's going to break first and how would I know if there's a problem?
4. How high can the LS6 rev before getting into trouble?

TIA :confused:

HummelS

1. No - it's "physics" - the rev limiter is "logic." Physics wins here.
2. If they can do CAGS to prevent one thing, why not the other? It could if it were designed that way, but it's not.
3. Probably the pushrods will bend - you'd hear it, most likely.
4. ???



[Modified by thevettenet CA, 6:06 PM 3/25/2002]

figment

UNFORTUNATELY, The rev limmiter is an electronic device that cuts fuel to the engine when the throttle is asking for more RPM than the valve-train can support. When you down-shift the rev limmiter is useless because it operates on electronics, not mechanics. There is no way to do this without obsurdly complex engine designs. Hope you dodged the bullet this time.

VetterMan

Briggrin...

Sorry to hear of your misfortunate experience.:sad:
I hope you were lucky and dodged the bullet of disaster.:blueangel:
Do yourself (and your engine/trans) a favor, install a Ripper shifter and avoid this sort of incident all together. :yesnod:

Good luck!
VetterMan

mqqn

Hi biggrin -
No.
No.
Engine internal parts, Engine quits running.
Redline.

hope this helps.

best regards -

mqqn

biggrin

Thanks guys!! Couldn't sleep and went out to drive the beast in my jammies at 11pm. Drove for 10 miles or so on city streets and highway. Everything seems OK. That was a close call! I'm going to look into the Rippie shifter tomorrow.

Chuck Harmon

I'm glad the engine didn't break on you during your test drive. That would have been a fun walk in jammies if it had! I'm sure no explanations would have been asked by passing cars, neighbors,etc! ;)

Chuck

ps, I did a similar thing in my 12 cylinder XJS. I accidently went from drive to reverse at 70 mph. Yes, it did engage, the back end howling and jumping all over the road. No, I didn't feel stupid either :(I did have to rebuild the trans about a year later and have always been pretty sure that my little stunt may have brought it on). For what it's worth, I believe the LS6 engine would handle occasional runs up to 7500rpm without any problem. I doubt you actually spun it as high as that. The tires probably took most of the punishment. Not as bad as my freeway reverse trick. JUST DON'T DO IT AGAIN:D

Chuck

hcvone

Get rid of the stock shifter, that will help. ;)

figment

check your oil daily for the next week or so just to be sure, and watch the oil pressure gauge closely.

You may want to do a pennance by changing the oil tonight:):hammer:

23wtha02

I've done it a couple of times in my SS. It feels like your car is about to break apart. I know it has scare the crap out of me. Just be careful and very focused when shifting. :yesnod:

JerryL

I did the same thing with my 01 (before the Ripper) and luckily avoided damage. I recommend having a competent mechanic take a look at all of your pushrods. That should not cost too much and it will help your peace-of-mind. As mentioned by others, get yourself a good shifter, I have not missed a gear, up or down, since installing the Ripper.

jeffsherman

Check the DIC for any codes there is one that logs if you hit 7400 I dont remberwhat it is but someone else will have it. If you did any mechanical damage the valves would probably show damage first. Check the fuel consumption numbers, if its down, you may have a bent valve.

BTW the engine should handle more than the redline by some margin and not break.

Chuck Harmon

Small blocks less stout and perhaps blue printed to a lesser extent routinely went 8000+ rpm. The fear with this engine is did the hydraulic lifters float enough to touch a piston to a valve? You can use an engine stethoscope, <$20 at Sears, or a long screw driver to listen for unusual valve train noises. You will have to remove the plastic covers, but you will be able to precisely locate any excessive lifter noises. It's not a bad idea to do this anyway just to familiarize yourself with the what the motor sounds like at various points when in good condition.

Chuck

figment

Good stuff:thumbup:

Press and hold options and then press Fuel 4 times while still holding the options button you must do this quickly. A message will appear saying "Diagonstics" then it will automatically read off the codes.
From: https://www.corvetteforum.com/techti...D=25&TopicID=1


[Modified by figment, 4:05 PM 3/26/2002]

biggrin

You guys are incredible! It's like having a room of mechanics. The other forums I've been in spend all the time talking about color matching the interior leather, wood etc. and how with a few simple mods they can 'take' a C5. Right............Thanks again!!

biggrin

Just did the diagnostic. Got code "60IPC U1160H" Went to http://www.c5-corvette.com/C5Dyno.htm, clicked on "IPC Display Codes" and basically it's a fault of the Instrument Panel Cluster loss of communication with the left door control module ie. a nothing fault. The list on that webpage is great. Maybe everyone should run a diagnostic to see what's cooking in their car--there's so electronics going on we or at least I don't realize. Makes something like an L88 that much 'purer'.

Chuck Harmon

biggrin,

Quote:
Makes something like an L88 that much 'purer'.
________________________________________ ______________________

My feelings exactly. You don't need to be a EE to work on the 69.

By the way, I went out to my Z to see about getting a benchmark vacuum reading for you. An erratic needle would possibly suggest a bent valve, but with the lopey idle, I wanted to see just how erratic a normal LS6 is. Where does one hook up such a device??? It wouldn't surprise me if there are no vacuum ports, only sensors. Does anyone know? Makes me appreciate the simplicity of the L88 all the more!

After taking off the beautiful red plastic covers, I also recognized that I can probably pull out the L88 in less time than I could get to the valves on the Z to adjust them. With advances in technology, you win some and you lose some! :smash:

This reminded me a friend who was looking at touring bikes. The Harley Store said that the bike is so simple, you can virtually rebuild the engine on the side of the road. The BMW Store said you would never need to worry about having to! I hope this applies with the new Vettes! ;)

Chuck

Z06-Goose

You should be fine. In cases like these, the pushrods are the weakest link.
If you've done any damage to the engine, you would've known by now.
Chalk this one on lady luck! :yesnod:


[Modified by Wicked LT1, 7:44 PM 3/26/2002]