Is it bad to Red line too often?

Right Robbie,

Too old and too brittle.


I never push mine that hard. Not until I get solid SS valves put in in the next couple of years.

 

This it what I was wondering. Since all modern cars have rev-limiters, how can you over-rev the car? With that said, one can only rev as high as the factory has set the limit. So, the next question in my mind is 'can hitting the rev limiter (say at a track event, repeatedly but not intentionally) cause any damage'? (I don't think I need to explain why I am asking this question) I would think not. Does anyone know?

RB

 

I remember a prior car manual saying not to remain at the redline for extended periods of time but going up to it was not detrimental.

In my 87 I just drive it at what is comfortable to me. I usually loaf around town, I don't get much joy in revving the engine in traffic, but when the highway opens in front of me I have a hard time not running through a couple gears. It is just fun for me to do and I like the sound. I've been doing lots of highway time and I make sure to stop at lots of rest stops so I get to take off from low speed again. My car seems to have such great torque at low revs that I don't worry about a range or a place to keep it. It gets enough highway miles to keep the engine clean on the inside.

On the car the original poster has, I'm not sure you can hurt it if you keep up on maintenance and take it on the highway from time to time. Drive the car as you wish. Running it to redline periodically shouldn't hurt anything.

 

On one of the early "Dream Car Tours" from Gotham Dream Cars, there was a red 360 Modena that literally went up in flames because the driver kept the car up against the redline for too long. There is probably a picture of this somewhere here on Fchat.

 

I believe that my engine suffered from track operation above redline and below fuel cutoff. I think this put rapid wear on the valve guides that ultimately lead to a head+job. You could hear the difference in the "song" of the engine after <maybe> a dozen seconds, one second at a time over a dozen laps. Durring this time, I never actually bounced the engine off the rev limiter, however I did see 8700 RPMs.

Still, it took another 20K miles for the damage to really show up on the leak down test, but I could hear the lack of song the whole time.

 

The internals of a motor contain metal on metal friction. With oil we lessen how damaging the friction is, but theoretically there is still X number of revolutions in a motor before something goes wrong. Driving at a constant high rpm just ads up the tally quicker of how many revs you have in your motor. Whereas, spirited driving and runs up to redline average out to be a much lower average rpm.

I have no problem exercising a car's motor to redline, and do so often at racetracks, but sustained high rpm driving is, arguably, pointless and definitely shortening of the life of the motor.

 

loads on an engine increase geometrically as the as the revs go up...

dragsters rebuild their engines after each run, which lasts only a few seconds and are limited by a red line as well, there is enough wear at the end of a run to justify a tear down

track cars usually go through their engines after each race, replacing worn items

there is a limit on how much an engine can stand, it wears a bit every time we turn it on red lined or not, at red line the forces are at the maximum, a mix of robust driving is part of a high performance car... it should not be a deterrant to enjoying the car... dragsters expect a rebuild only after a few seconds... hopefully the enjoyment doesn't end before its' anticipated time

 

Thermal cycles of a dragster motor are quite different than a water cooled motor. Plus they are only designed to spin over less that 1000 times per run. Race engines are designed on the ragged edge of destruction. I think production models have a lot tolerance. How long would a company last, if all their motors popped when red line was achieved a few times??)))
But agreed, more stress, more material wear. Same goes to the human body.

 

Quadradically (X**2)

Nirtromethane engines have lost compression by the 800 ft mark, the exhaust valves are completely burned out.

Prostock motors can last many races. I have a friend who races a 3000 HP doorslammer (twin turbos but like a PS car) and he tells me he gets 100 passes on a motor running in the 6.5 sec range (1/4 mile).

 

That is very interesting to me. When I had my 355, I wondered about this very thing and whether or not you would hear or feel a difference.

Mitch, do you think your engine was compromised from that moment but it took 20k miles for the engine to lose power or tractability or something? Or do you think you lost something right away? Lastly, do you think that the new valve guides prevent a reoccurrence under similar conditions?

 

Yes it is, by definition. If it isn't, then it it isn't "too often," it is just fine. No matter how often you do it, if you do it "too often" it is too much. So don't do it "too often," do it just right.

 

*sigh*

drag engines are completely different compared to a road car engine.

track cars don't strip their engines after every race. IIRC Porsche GT3 RSR's have to rebuilt every 80 hours, at least, that's what they recommend. Plenty drivers on a more tight budget than the teams that do ALMS or GT3 class racing have gone to over 200* hours. These engines are getting run all the way to the redline and don't really live below 4-5000 rpm.

If you take average speed of 150 km/h per lap at 80 hours that's 12000 km. The guys that do 200 hours on them do 30K. Service intervals on a 599 are 18000 km if I'm not mistaken...

And a 599 isn't doing it's work out all day from 5000 to 8500 revs. It spends plenty time below that.

As mentioned before in this thread, it'll be fine. Ferrari set the rev limit because they deem that save enough to still reach the service intervals without the engine exploding into oblivion.

*200hrs is of the top of my head. Could have been 150. Can't be bothered to search for source.

 

I could hear a difference in the sound, I could feel no difference in the performance. The engine lost some of its sonourous melody, without loosing any of its bark.

In addition, at the time the engine was diagnosed, the only time the engine ran gruff, was after the battery was switched off for a couple weeks and the car was started and had to acquire new idle parameters. It was still running at least OK-ish. It was probably not even down 20 HP if put on a dyno.

But there was a water loss incident that cannot be counted out of serious contribution to the engine leak down issues especially those of the liners.

However, there is no getting around the fact that the valve guides had some very significant wear on them. A couple were more than 1mm out of round (about 40X the wear limit).

 

+1

I say vary the RPM's as much as you can, avoid the limiter "if you can", but don't keep that machine running at low RPM most of the time, am sure most folks would agree that their engines are happier when run hard. Reason for this is they were built, tuned, and tested to do just that without breaking apart. and I think there is a fine line between hard driving and abusive driving.

Ferrari builds these engines for optimum performance AND maximum reliability at peak power, optimum performance is No Where near 4K RPM or even 6K RPM. I've seen them test the new 458 Italia engine and I will tell you they were not cruising around town at 5K RPM during trial testing.

If you use common sense when running them hard you're doing the Right Thing IMO.

 

I had heard that there could be some sort of problem with replacement head gaskets and R&R procedures, such that it is sometimes difficult to get a really good "seal" when the heads are removed and reattached.

Should drivers with replacement head gaskets be any more nervous about driving their Ferrari hard than owners stilll using the original head gaskets?

 

This^^
Revs kill, ask a race engine builder for TBO shifting at X RPM vs X+500 RPM. The line is red for reason, just because it doesn't break it doesn't mean it's good for it.

 

Yes, it's bad to redline too often. The question is, what constitutes too often in a particular Ferrari model? Most of these cars can lap a road course for 20-30 minutes at a time without issue shifting at red line (to the engine at least, brakes are another matter on some). I think you'll have a tough time hurting the engine on the street unless you drive like a complete maniac, in which case the police and trees/other obstacles lining the road will probably be a more immediate concern than hurting the engine.

 

At the Ring we run Flat out at Redline for 40 seconds a lap and up to the redline for every shift.

Frankly upon tear down we noticed very little wear.

On the street I often run up to red line.

I've driven Exotics on the Street for over 600K miles and have never had an issue due to redlining.

 

"sigh"

I can't belive this thread has made it 4 pages.

This reminds me of the how often should I change my timing belts.

I have heard this debate my whole life. Re: Motorcycles, I remember back in the 80's Kawasaki actually published a document explaining how running at redline was much better and cause less wear than running at too low RPM (lugging). That stated that all the fluids would be warm and flowing properly, basically they said the engine would be happier.

Then I laughed and laughed when I read in a motorcycle magazine whereas the author stated that you should not blip your throttle at red lights because you should save those RPM's and add them to your engines life, sort of like a savings account...LOL!!

If your going to buy a sport vehicle you should drive it "sporty".

 

Ditto.

 

This^^is as authoritative as possible!!

 

Talking about modern cars, well, when I bought the 2010 Porsche GT3 I was told by mechanics and racers to get the revs going, driving it like a grandma was gonna bite me in the ass sooner than later. They said these motors need to be driven in a spirited manner or carbon build up will happen.

 

Thinking about this, I never drove my cars all to frequent to redline while street driving, I was always worrying of wear and a rebuilt, but if I'm going to be redlining the car almost all the time possible then why buy something over a 308gtb. The other models are too fast for this type of driving in public streets. Then a 308 will offer more chances for redlining a Ferrari v8, maybe my next purchase should be just that and not a modern wonder. This thread has made me realize what I'm really after, is not a faster car, but one that will allow me to drive hard, run through the gears 'till 5th instead of primo, secondo, terzo and game over. At the end of the day this thread has been helpful in a way.