Jump to content

Welcome to RennTech.org Community, Guest

There are many great features available to you once you register at RennTech.org
You are free to view posts here, but you must log in to reply to existing posts, or to start your own new topic. Like most online communities, there are costs involved to maintain a site like this - so we encourage our members to donate. All donations go to the costs operating and maintaining this site. We prefer that guests take part in our community and we offer a lot in return to those willing to join our corner of the Porsche world. This site is 99 percent member supported (less than 1 percent comes from advertising) - so please consider an annual donation to keep this site running.

Here are some of the features available - once you register at RennTech.org

  • View Classified Ads
  • DIY Tutorials
  • Porsche TSB Listings (limited)
  • VIN Decoder
  • Special Offers
  • OBD II P-Codes
  • Paint Codes
  • Registry
  • Videos System
  • View Reviews
  • and get rid of this welcome message

It takes just a few minutes to register, and it's FREE

Contributing Members also get these additional benefits:
(you become a Contributing Member by donating money to the operation of this site)

  • No ads - advertisements are removed
  • Access the Contributors Only Forum
  • Contributing Members Only Downloads
  • Send attachments with PMs
  • All image/file storage limits are substantially increased for all Contributing Members
  • Option Codes Lookup
  • VIN Option Lookups (limited)

Recommended Posts

Posted

Hi everyone! New to the forum and my first question/topic. I am the proud owner of a 54k km 1998 Mk1 GT3 Club Sport which I was happy (read stupid) enough to allow a friend to try the other day. While accelerating, he miss shifted from 4th into 3rd ( he was trying to upshift) burying the rev needle in the process. Granted he lifted enough during the shift that he lost some momentem and the gear slotted in without drama. There are no check engine lights and the car seems to running absolutely fine with no loss in power or additonal valetrain noise. I have read that the GT3 motor can actually rev safely to over 9000rpm but wanted to know if anyone had specific info on this. I have also often heard about type 1 and type 2 over revs - and was looking for a bit of clarifaction on these points and potetnial troubleshooting. Obviously one can easily float a valve (s) in such an instance, but as I mentioned the motor seems fine. Any help/advice would be greatly appreciated! Thanks!

Posted

Had to say what short term damage occurred but if it's over revved enough times the connecting rod will try and escape the engine case. There is always a risk of damage each time this happens but to what extent who can say.

  • Moderators
Posted

We didn't get the MK I GT3 in the US, so, we may not be familiar here with what the ECU is recording and can report....but, I would think that a leak-down test could be diagnostic. Warning: leak down tests can report false positives.......like due to a bit of carbon temporarily holding a valve open. If a leak down shows good even pressure, though, that would give you peace of mind.

Posted
Had to say what short term damage occurred but if it's over revved enough times the connecting rod will try and escape the engine case. There is always a risk of damage each time this happens but to what extent who can say.

Thanks for your input! Luckily this was the only time - granted it cpuld take one error of this magnitude to float a vlave or throw a rod. As I mentioned I feel calm only in that the engine seems absolutley sound. I will try to schedula a dyno run to see if it has any power loss.

Posted
We didn't get the MK I GT3 in the US, so, we may not be familiar here with what the ECU is recording and can report....but, I would think that a leak-down test could be diagnostic. Warning: leak down tests can report false positives.......like due to a bit of carbon temporarily holding a valve open. If a leak down shows good even pressure, though, that would give you peace of mind.

Thanks Craig! As I mentioned previously, I will probably have a dyno run done at which point I could also have a compression check. I had both done a little less than a year ago so I have the numbers to compare. As long as she continues to run smoothly I think I can say I dodged a bullet on this one!

Posted

Thats the worse kind of over-rev you can get.. The engine is being pulled externally. The load is different. The stuff of broken hearts. The harm is less the revs than the source.

But before you really make yourself nuts:

What did the engine really peak at? If you don't know, get a reading from the DME.

Posted
Thats the worse kind of over-rev you can get.. The engine is being pulled externally. The load is different. The stuff of broken hearts. The harm is less the revs than the source.

But before you really make yourself nuts:

What did the engine really peak at? If you don't know, get a reading from the DME.

Thanks for the input Dan - Honestly I am somewhat at ease at the moment but you are absolutley right in that it is by far the worse type of overrev. I know someone that did it in an M5 and it practically through the engine out the car -needless to say they had to drop a whole new unit into it.

I was in the passenger seat but I saw an honest 8400-8500 rpm. Granted I know Porsche motorsport declared that the engine could 9000 without breaking upon the car's introduction (a decade ago!)- and since the incident - the car has continued to run flawlessly. I feel pretty lucky at the moment and will continue to keep my fingers crossed. As I mentioned the car will go for a dyno run and compression check soon, and if it is significantly down on power (beyond the noraml margain of error) or starts to run poorly than I will probably have to consider opening her up. But lets cross that bridge when and IF we get to it!

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.