rev limiter

[lmritter]

Greetings:

Question: If a rev limiter " kicks in" does it do so before any engine damage occurs. Also , does anyone know what rpm level Porsche tests thier 997 3.8Ltr engines at before they leave the factory.

Thanks

Chromedome

[White987S]

Imritter, the rev-limiter does NOT protect you on a down-shift. So, if you miss a gear, you could do damage.

Also, the DME records all redline activity and near redline activity. Porsche can read this data, and possibly use it to prove you have miss-treated the car, and even deny a warranty claim.

[chaser]

All this is true...but I'm sure that there is no one here who hasn't hit the limiter in 1st gear. I'm sure Porsche recognizes this as well and forgive our sins for this minor infraction unless it is all to frequent.

[PAULSPEED]

Hi,

The rev limiter is at 7,100RPM. If you get a

GT-3 then you will rev it to 8,300RPM.

Paul

[jmj996]

Greetings:

Question: If a rev limiter " kicks in" does it do so before any engine damage occurs. Also , does anyone know what rpm level Porsche tests thier 997 3.8Ltr engines at before they leave the factory.

Thanks

Chromedome

I don't believe you'll ever get a guaranteed answer to the first question, but you can assume that Porsche engineers set the rev limit at an RPM that was statistically proven to fall below a level that would damage the engine (assuming no unusual wear or weakness and operating conditions within tolerance). I believe you will find many people (myself included) that have felt the rev limiter kick in and haven't noticed any damage to their engines. Given the number of miles I had on my 986 and now my 996 after having hit the rev limiter on both, I wouldn't even be too concerned about buying a Porsche that has hit the rev limiter, but the other comment about it being stored in the DME is interesting. I would like to know for certain if it is stored, and if it can be cleared out by disconnecting the battery (and if so, shouldn't everyone briefly disconnect the battery before getting any maintenance done?).

[chaser]

I don't believe you'll ever get a guaranteed answer to the first question, but you can assume that Porsche engineers set the rev limit at an RPM that was statistically proven to fall below a level that would damage the engine (assuming no unusual wear or weakness and operating conditions within tolerance). I believe you will find many people (myself included) that have felt the rev limiter kick in and haven't noticed any damage to their engines. Given the number of miles I had on my 986 and now my 996 after having hit the rev limiter on both, I wouldn't even be too concerned about buying a Porsche that has hit the rev limiter, but the other comment about it being stored in the DME is interesting. I would like to know for certain if it is stored, and if it can be cleared out by disconnecting the battery (and if so, shouldn't everyone briefly disconnect the battery before getting any maintenance done?).

Excellent question.........

[Loren]

What is stored in the DME has been covered many times here. Do a search and you find many pics and explanations (search for "stage").

Rev limiters reports are done in "Stages". Stage 1 are okay as they over-revs controlled by the DME. Stage 2 and beyond are all potentially engine damaging.

[david_yorkshire]

blimey - I've hit the rev limiter in 5th gear regularly - you guys can't be trying hard enough !

David