Split second of over-rev... damage? - Team Camaro Tech
Team Camaro Tech join team camaro
  



Registered users (free) do not see these large ads

Fourth Generation 1993-2002


Reply
 
LinkBack Thread Tools
Display Modes
Old Sep 17th, 08, 08:02 PM   #1 (permalink)
 
Join Date: Sep 2008
Posts: 4
Split second of over-rev... damage?

Hey - I've got an LS1 with hardened pushrods and dual valve springs, spec 3 clutch, stock t56, and a driveshaft + rear end that are both rated for over 1000 hp. I was on the highway today, and I ran the car most of the way through third, went to grab 4th, missed, hit second, dropped the clutch -- I don't know if I let it all the way out or not... but if so, it couldn't have been in gear for over a quarter second. Anyway, it scared the sh** out of me. The car drives fine. No weird noises from the valvetrain. Still feels like its running at full power, tranny feels totally fine. Would I know by now if the valvetrain was damaged? What else might be damaged, engine wise, by a split second of overrev?

Thanks!
mitchcoleman is offline   Reply With Quote Quick reply to this message
Old Sep 17th, 08, 08:15 PM   #2 (permalink)
Gold Lifetime Member
 
Skeeter55's Avatar
 
Join Date: Feb 2008
Location: CA
Posts: 6,628
Re: Split second of over-rev... damage?

What do you consider overreving (WHAT RPM)... You would know by now if the valves kissed the piston or each other... That old sound of clack, clack and pop, pop and rattle, rattle would be heard.
__________________
I NEED TO HIT THE LOTTERY
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
Skeeter55 is offline   Reply With Quote Quick reply to this message
Old Sep 17th, 08, 08:18 PM   #3 (permalink)
 
Join Date: Sep 2008
Posts: 4
Re: Split second of over-rev... damage?

****, it musta been 9k-9.5kish, my redline's 7100.
mitchcoleman is offline   Reply With Quote Quick reply to this message
Old Sep 17th, 08, 08:25 PM   #4 (permalink)
Gold Lifetime Member
 
Skeeter55's Avatar
 
Join Date: Feb 2008
Location: CA
Posts: 6,628
Re: Split second of over-rev... damage?

WOW no way it reved that high, if anything the valves floated and you got lucky.... Why don't you have a rev-limiter on it.
__________________
I NEED TO HIT THE LOTTERY
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
Skeeter55 is offline   Reply With Quote Quick reply to this message
Old Sep 17th, 08, 08:30 PM   #5 (permalink)
 
Join Date: Sep 2008
Posts: 4
Re: Split second of over-rev... damage?

It has a rev limiter on it, but that doesnt save you from downshifting overrevs does it? I mean, the engine wasn't firing at that speed, you could hear it cut out for that split second. You can still damage it just spinning at that speed.
mitchcoleman is offline   Reply With Quote Quick reply to this message
Old Sep 17th, 08, 08:33 PM   #6 (permalink)
Senior Tech
 
BigBlock1969RS's Avatar
 
Join Date: Jun 2007
Location: Los Angeles, CA
Posts: 2,083
Re: Split second of over-rev... damage?

I'd pull the oil filter and cut it up. If you chunked anything in the mis-shift it will show up in your oil and filter. Good time to change the oil anyways just in case some gunk was broke loose.

I think you are fine thou, you would heard it if a piston kissed a valve. If you hear noise or find a lot of shavings you could always do a compression and leakdown test see if anything it out of wack.
__________________
Ed

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
BigBlock1969RS is offline   Reply With Quote Quick reply to this message
Old Sep 17th, 08, 08:35 PM   #7 (permalink)
Gold Lifetime Member
 
Skeeter55's Avatar
 
Join Date: Feb 2008
Location: CA
Posts: 6,628
Re: Split second of over-rev... damage?

Then your all good, the rev-limiter did its job. Some times its hard to hear when the rev-limiter is shutting down. What is the rev-limiter set at.
__________________
I NEED TO HIT THE LOTTERY
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
Skeeter55 is offline   Reply With Quote Quick reply to this message
Old Sep 17th, 08, 09:09 PM   #8 (permalink)
Senior Tech
 
Join Date: Oct 2005
Location: SoCal
Posts: 3,829
Re: Split second of over-rev... damage?

Quote:
Originally Posted by Skeeter55 View Post
Then your all good, the rev-limiter did its job. Some times its hard to hear when the rev-limiter is shutting down. What is the rev-limiter set at.
I don't think you are understanding what happened.
He was near the redline in 3rd gear, meant to shift into 4th but got 2nd instead. If you let out the clutch in 2nd gear when the car is moving at top speed for 3rd gear, the engine can hit very high RPM's through mechanical forces.
No rev limiter is going to save you from that.
It's called the "Money Shift", and it usually causes instantaneous damage.
Sounds like Mitch caught it in time and saved the engine.

Last edited by 68 Ragtop; Sep 17th, 08 at 09:28 PM.
68 Ragtop is offline   Reply With Quote Quick reply to this message
Old Sep 17th, 08, 09:47 PM   #9 (permalink)
 
Join Date: Sep 2008
Posts: 4
Re: Split second of over-rev... damage?

Quote:
Originally Posted by 68 Ragtop View Post
I don't think you are understanding what happened.
He was near the redline in 3rd gear, meant to shift into 4th but got 2nd instead. If you let out the clutch in 2nd gear when the car is moving at top speed for 3rd gear, the engine can hit very high RPM's through mechanical forces.
No rev limiter is going to save you from that.
It's called the "Money Shift", and it usually causes instantaneous damage.
Sounds like Mitch caught it in time and saved the engine.
Exactly what happened. Ragtop, if there were damage, would it most likely be immediately noticable? I mean this is an all or nothing deal for the most part, right? I'd know if I f***ed my motor up?
mitchcoleman is offline   Reply With Quote Quick reply to this message
Old Sep 17th, 08, 11:04 PM   #10 (permalink)
Senior Tech
 
Join Date: Oct 2005
Location: SoCal
Posts: 3,829
Re: Split second of over-rev... damage?

Quote:
Originally Posted by mitchcoleman View Post
Exactly what happened. Ragtop, if there were damage, would it most likely be immediately noticable? I mean this is an all or nothing deal for the most part, right? I'd know if I f***ed my motor up?
With most motors the damage is immediate. I know with BMW's it usually takes the valves out right away. With LS motors, I don't know if there is any latent damage. Take it easy for a while and see if there is any funny noises or loss of power.
Thankfully you put the clutch in quick, here is what happens if you dont:
[IMG]http://www.kontraband.com/videos/1472/OH-****/[/IMG]
68 Ragtop is offline   Reply With Quote Quick reply to this message
Old Sep 18th, 08, 02:31 PM   #11 (permalink)
Gold Lifetime Member
 
Join Date: Oct 2007
Location: San Diego, CA
Posts: 2,717
Re: Split second of over-rev... damage?

Although not as high, I over revved my LS1 when I attempted to manually shift my A4 (I wasn't about to give it up to a 5.0 Fox body). It went to N and winged up there. Engine ran fine but I pulled the valve covers that weekend and discovered 3 bent pushrods. Not bent enough to not work but not straight either.

BTW, they were stock pushrods. I replaced them with a set of hardened Comp pushrods.
__________________
67 Camaro: 454/TH400/4.10 12 bolt. Lots of options: PS/PDB/PW, tilt, tach, gauges and more. K-K + 797-Z...

"Politics is the art of looking for trouble, finding it whether it exists or not, diagnosing it incorrectly and applying the wrong remedy" - Sir Ernest Benn
PowerWindows is offline   Reply With Quote Quick reply to this message
Old Sep 18th, 08, 05:26 PM   #12 (permalink)
Senior Tech
 
Join Date: Sep 2006
Location: detroit
Posts: 2,290
Re: Split second of over-rev... damage?

[quote=mitchcoleman;1068076]It has a rev limiter on it, but that doesnt save you from downshifting overrevs does it? I mean, the engine wasn't firing at that speed, you could hear it cut out for that split second. You can still damage it just spinning at that speed.[/quote

Correct..even more so when you went from the crankshaft delivering power and then being unloaded and driven from the rear.Hopefully the powertrain is stout enough and you had some momentary rear tire slippage when the clutch attempted to engage on the downshift.I would not sweat it..sounds like you dodged a bullet..but rolling some pushrods on glass would add to your peace of mind.
__________________
George
68 Camaro
8-71 blown 461 Rat on E-85
fatblock is offline   Reply With Quote Quick reply to this message
Old Oct 1st, 08, 06:00 AM   #13 (permalink)
Senior Tech
 
Join Date: May 2005
Location: PA
Posts: 1,339
Re: Split second of over-rev... damage?

Quote:
Originally Posted by Skeeter55 View Post
Then your all good, the rev-limiter did its job. Some times its hard to hear when the rev-limiter is shutting down. What is the rev-limiter set at.
the rev limiter isnt going to help when the car is put in the wrong gear
victimizati0n is offline   Reply With Quote Quick reply to this message
Reply
Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the Team Camaro Tech forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid email address.
NOTE we receive a lot of registrations with bad email addresses. IF you do not receive your confirmation email you will not be able to post. contact support and we will try and help.
Be sure you enter a valid email address and check your spam folder as well.

Email Address:
Location
Location
First Name
Rather than just Hot69, gotta real name?

Log-in


Thread Tools
Display Modes

Posting Rules
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


» Recent Discussions
awaiting spring
Yesterday 04:00 AM
Last post by allanjs
Yesterday 08:23 PM
13 Replies, 159 Views
Over Drive Trans or...
Oct 19th, 19 06:19 AM
Last post by mahunt
Yesterday 08:06 PM
6 Replies, 135 Views
Where did everyone go?
Oct 13th, 19 08:07 PM
Last post by allanjs
Yesterday 08:05 PM
62 Replies, 1,843 Views
Narrowing a Impala 12...
Aug 2nd, 19 01:00 PM
by X1169B
Last post by mahunt
Yesterday 08:04 PM
16 Replies, 869 Views
BBC water bypass line
Oct 19th, 19 07:12 PM
by Foss396
Last post by Lonnie P
Yesterday 07:20 PM
12 Replies, 191 Views
Success and failures...
Yesterday 06:56 PM
Last post by Cunning69
Yesterday 07:03 PM
1 Replies, 44 Views
Just why ?
Oct 19th, 19 04:34 PM
by DOUG G
Last post by stevo camaro
Yesterday 06:58 PM
6 Replies, 228 Views
Backyard buried...
Apr 5th, 05 04:12 PM
Last post by stevo camaro
Yesterday 06:55 PM
1 Replies, 183,880 Views
Quiet High Performance...
Oct 18th, 19 07:18 PM
Last post by kv67ssrs
Yesterday 06:30 PM
6 Replies, 196 Views
Need the carb guy's
Yesterday 05:55 PM
Last post by stevo camaro
Yesterday 06:15 PM
2 Replies, 56 Views
Powered by vBadvanced CMPS v3.2.3

All times are GMT -7. The time now is 01:57 AM.



Camaros.net - 2009 AutoForums.com
vBulletin Security provided by vBSecurity v2.2.2 (Pro) - vBulletin Mods & Addons Copyright © 2019 DragonByte Technologies Ltd.
User Alert System provided by Advanced User Tagging (Pro) - vBulletin Mods & Addons Copyright © 2019 DragonByte Technologies Ltd.