What do you think about redlining?

[AlaskaBlue]

Many people have different views on what will happen to an engine when it is redlined. Some say that an engine can be redlined and nothing will happed because it does not spend very much time at high RPMs. Others say that redlining is dangerous and it could potentialy blow the engine everytime one does it.

What do you think about redlining?

[maurolin]

I have done it before on my M3 and the Ti aswell.
7300 rpms when my rev limiter hits....
not scarry.... but per my dyno readings... on an S52, after 6500 rpms there is power loss... so I set my shifting right at 6500 and if I miss... I still have some room to play safe.

[hotdog19d]

I redline mine almost daily.....

[AlaskaBlue]

I redline mine often too and I have a lot of miles. The car just seems like it laughs at whatever I throw at it. I love it.

[JedzE36/5]

the redline is there to protect the motor from extreme rpms.

[AlaskaBlue]

The question is not why there is a redline. It is whether shifting at redline will do that much damage or if it really does damage the engine at all.

[aceyx]

it's impossible to ignore why there is a redline in the first place and then try to answer your question.

my question is why you would wait so long to shift? if you just forget every once in a while, it's likely that there's no harm done. if you're driving everywhere in first bouncing the needle, then you might grenade the motor, but if that's the case you should go buy an automagic.

[AlaskaBlue]

All I wanted to know is what the members of this forum thought about shifting at or near redline in a drag or autocross situation. Not daily driving to school or work.

From your experiences does it hurt the engine or not with a shift point between 6250 to 7000 rpms?

[maurolin]

just redline the bit@#! if it blows up... get an S52! HAHAHA

[1996 328ti]

I was told redline was determined by how long the engine can sustain a certain high RPM. Redline is conservative IMHO. Nothing wrong with running up to redline although I wouldn't do it under normal driving. At the track I'm constantly at just below redline coming out of turns. Plus the car is chipped so redline is even higher. I'm not worried.

[John Firestone]

BMW publishes both a maximum peak RPM you should never exceed (e.g. 6500 rpm for the M42/M44) and a maximum sustained RPM, a few hundred RPM lower, that you should stay below over longer periods. You shouldn't have any trouble with short excursions to either provided you properly maintain the car and first fully warm up the engine.

You may also have no problems running the engine at or near the red zone for long periods, but then again you may become one of the unlucky. A prudent reduction below the red zone of the sustained RPM between shifts will lengthen the engine's life.

[ZeroG]

Just thought I would drop in my 2 cents.

Ok so the topc is red lining. You really need to define the term do you meab letting the car run a rev limiter wiht the needle boucing or so you mean just leting the car get a little in the red.

In my opinion for either a stock BMW cannot be reved over 7300 RPMS anymore and you risk messing up the harmonic vibration dampener on the crank and risk throwing a rod.

If you are just talking about drag racing where you only got to where the needle gets a little red you should be OK as long as you keep your engine in good working order. The main thing that I would worry about if a lifter getting stuck and bending or blowing a valve.

Now if it is Autocross you are thinking about I would say it puts a little more stress on your engine then a16 second drag race. I autocross occasionally and most of the time you never get out of second gear and find yourself maintaining 6000 RPMS for the entire minute to minute and a half lap. WHich is a lot of stress in my opinion.

-Chad

[John Firestone]

There are plenty of people around here who maintain 6000 rpm in fifth for much longer than a few minutes. Usually nothing happens.

[ZeroG]

Originally Posted by John Firestone

There are plenty of people around here who maintain 6000 rpm in fifth for much longer than a few minutes. Usually nothing happens.

I do agree that you are right but I think the stress level at 6K in second is greater then in fifth, especially when making .5g latteral turns with all the oil in your oil pan stuck to one side of the pan.

Just a thought.

-Chad

[AlaskaBlue]

Originally Posted by John Firestone

There are plenty of people around here who maintain 6000 rpm in fifth for much longer than a few minutes. Usually nothing happens.

I didn't even know a 318 could push the car all the way to 6,000 rpms in 5th I have never had the nerve to try it. I want a better suspension first.
Is that stock or modified?


And I meant just a little in the red then SHIFT.