How does "red lining" clean the engine?
#1
How does "red lining" clean the engine?
I've got an '09 RX-8 R3, my first rotary. I'm enjoying the car immensely, but I'm also trying to understand more about this unique powerplant.
I've read many posters in this forum and other rotary forums advocate the benefits of taking the car to the red line at least once a day to "clean out" the engine. I'm no engineer but I think I can understand basic engineering concepts. So, I'm wondering if someone can explain the engineering theory that would explain how high RPMs "clean" the engine.
If the advice is correct, I can think of only three possibilities as to what might be happening: 1) high RPMs produce more heat and the increased heat helps clean out combustion deposits; 2) high RPMs somehow increase the friction of the apex seals on the wall of the combustion chamber; or 3) high RPM's result in a cleaner burn of the air/fuel/oil mixture (which might reduce new deposits but I can't see how it would "clean" old deposits).
Can someone provide me an engineering explanation to support the advice "drive it at the red line at least once a day to clean out the engine"?
I've read many posters in this forum and other rotary forums advocate the benefits of taking the car to the red line at least once a day to "clean out" the engine. I'm no engineer but I think I can understand basic engineering concepts. So, I'm wondering if someone can explain the engineering theory that would explain how high RPMs "clean" the engine.
If the advice is correct, I can think of only three possibilities as to what might be happening: 1) high RPMs produce more heat and the increased heat helps clean out combustion deposits; 2) high RPMs somehow increase the friction of the apex seals on the wall of the combustion chamber; or 3) high RPM's result in a cleaner burn of the air/fuel/oil mixture (which might reduce new deposits but I can't see how it would "clean" old deposits).
Can someone provide me an engineering explanation to support the advice "drive it at the red line at least once a day to clean out the engine"?
#8
Huge hole is huge
It's been said for years that redlining the rotary helps to get rid of carbon deposits...
There are both sides to the argument who believe it works or doesn't. I'm the person who doesn't believe it because I've seen plenty of 13B's with a lot of carbon at low miles that I know are beaten on...but that's OK. These engines were made to rev high, so why NOT do it?
It feels oh so good, and gives you a euphoric feeling.
There are both sides to the argument who believe it works or doesn't. I'm the person who doesn't believe it because I've seen plenty of 13B's with a lot of carbon at low miles that I know are beaten on...but that's OK. These engines were made to rev high, so why NOT do it?
It feels oh so good, and gives you a euphoric feeling.
#9
IRC Founder
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when you redline, the little tiny unicorns inside your engine get really excited and start to jump up and down, with there horns chiping away at the carbon buildup... thus cleaning your engine.... dont listen to the others, they know nothing of the mystical creatures.
#12
Hit & Run Magnet
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when you redline, the little tiny unicorns inside your engine get really excited and start to jump up and down, with there horns chiping away at the carbon buildup... thus cleaning your engine.... dont listen to the others, they know nothing of the mystical creatures.
#14
I think much of the redlining suggestions have had their roots in OMP output. Up until the release of the accessport, OMP volumes were dependant on Mazda's upgraded PCM flashes. While the new flashes are said to increase OMP output, I think with many of the 2004 and 2005 models we were seeing those who would redline the motor having longer lasting engines.
No doubt people were getting proper oiling in the upper RPM bands that they were not getting with lower RPMs. More aggressive driving means more oil injection into the motor.
This is why it's important for RX8 owners to look into the accessport even if you're not concerned about performance gains. OMP increases, fan speed changes and some other tweaks will help the car run better and your motor last longer. Sure, $700 is a lot of money but that's a downpayment on a new motor should you not get one under warranty.
I still believe in not babying these motors. Drive these cars hard as that's what they were designed for.
No doubt people were getting proper oiling in the upper RPM bands that they were not getting with lower RPMs. More aggressive driving means more oil injection into the motor.
This is why it's important for RX8 owners to look into the accessport even if you're not concerned about performance gains. OMP increases, fan speed changes and some other tweaks will help the car run better and your motor last longer. Sure, $700 is a lot of money but that's a downpayment on a new motor should you not get one under warranty.
I still believe in not babying these motors. Drive these cars hard as that's what they were designed for.
#15
What mawd bug?
iTrader: (3)
That's something I'm not sure of. Most likely there will be detonation in that RPM range since the port doesn't open, but detonation doesn't always cause a CEL. I've never had issues with redlining my car, I love to do it
![Smilie](https://www.rx8club.com/images/smilies/smile.gif)
#16
Yes, as far as I know there will be a CEL if the ports are not able to open.
I know as a fellow rotary owner got a CEL when there was a stuck open port on his renesis.
I know as a fellow rotary owner got a CEL when there was a stuck open port on his renesis.
#18
Lubricious
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And of course, the increased gas velocities and rapid temperature changes may help loosen Carbon deposits in general.
#19
I don't buy Kool-Aid
#20
I would think you need load + sustained high rpm + WOT to be in full effect. Maybe i'm wrong though
#21
Rotary Powered Countryboy
yeah first there are ports that need a "workout" so they don't get jammed with carbon and will not open..
Also running the car hard so it heats up will get that carbon stuck on the rotor and housing to loosen and the exhaust gases will push it out... And I believe that it has to do with some of the oiling of the engine also the harder it is ran the more oil/lube it gets and hopefully getting the engine to last longer(of course premixing helps with this...off topic i highly reccommend premixing started a couple months ago and love it
Also running the car hard so it heats up will get that carbon stuck on the rotor and housing to loosen and the exhaust gases will push it out... And I believe that it has to do with some of the oiling of the engine also the harder it is ran the more oil/lube it gets and hopefully getting the engine to last longer(of course premixing helps with this...off topic i highly reccommend premixing started a couple months ago and love it
#23
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#24
Huge hole is huge
I've never let the engine warm up before driving off. I do as the manual states, let it idle for around 5-10 seconds, then take off. I've never had any sort of a problem with that. That's why they say to not drive too hard above 4k RPMs....the car is meant to be driven, not be some random and quirky thing you can't drive half the time.
#25
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