Well.remember that 5K with a load on it (i.e.-driving down the road) versus 5K freewheeling (i.e.-sitting idle) is totally different to the engine. With the load on it, the engine is designed to push against that load, but when freewheeling, there is no push back against anything and parts become quickly disoriented.Next time 'peer' tells you to rev it up, ask them how much money they have in their pocket. And when they ask why, tell them so they can pay you for the damage it's doing to the engine. Don't let morons goad you into blowing something up so they can walk away and laugh. It's not worth it.

• Z20let Bad Knock At 5k Rpm 1
• Z20let Bad Knock At 5k Rpm 2017

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My buddy and I were talking when we both noticed the knocking sound getting progressively louder and louder. At one point, I think the engine lost some power because it kicked into gear and cranked up to about 4500 RPM on level ground (tops out at 5K) and thats when it really started to get bad.

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• I would imagine most of you guys are more familiar with the Vauxhall or Holden badge, but it's the same car with the same Z20LET Turbo Ecotec engine. Anyways, when driving, the turbo kicks in at 2500 rpm, as usual, but when I reach 3500 rpm, I hear what sounds like the wastegate opening, accompanied by a slight loss in power.
• The knock feedback learning is -1.75 also for like 1 second for example i am doing a small pull 3rd gear form 3k rpm and do a pull till 5k rpm i look at my AP and on the guage on the bottom left it says -2.80 knock feedback but the actual gauge says 0 is this something to be worried about?

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Z20let Bad Knock At 5k Rpm 1

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Hello.After a long trip in Germany this summer, i got in a debate with my friends about how its really 'bad' to drive so fast that you keep your car at a high RPM for a long time, or that you run your RPMS high when accelerating.Everyone seems to 'complain' that you allways should keep your RPMs as low as possible (shift early), and never drive so fast that you go past 3000 RPM with a TDI engine that has a rev-limit at about 5000.Is this true? Does high RPMs tear / wear out your engine a lot quicker, or is it acceptable to lets say, drive 200 KM/h at 4000 RPM for 2-3 hours straight?

(TDI engine, RPM-limit at 5000).I've allways been under the impression that engines are usually tested and designed to be able to handle high RPMs just as fine as low RPMs, as long as you take good care of the engine. (Change oil+ filter, air-intake filters, etc.). Naturally, high RPMS require more lubrication, cooling and such, but is it really that 'damaging' to let the engine really hit high RPM-numbers for long times as long as you keep your cars lubricants, fluids and filters in check? I know that especially turbo'd cars are oil-sensitive, as the turbo require really good cooling, but is it damaging in the 'long term' to let an engine run at high RPMs?As you probably have noticed, im no way a mechanic, and i know that someone here knows a good answer to this.Thank you, and pardon my english, non-native writer.

This is probably the best answer I've seen in this thread.Manufacturers design the engines to run in a range of acceptable speed for performance. Higher RPM within a certain range isn't terrible for the engine, but it will increase wear on parts and fluids.This is why I tell people who regularly drive fast and use their full range of engine speed to change their fluids more frequently. Oil doesn't magically break down at a specific mile marker, it gets worn out by use.

Same goes for coolant, constant heating and cooling break it down and turn it acidic, making it lose it's properties. Imo the heat isn't the biggest issue - wear on the valvetrain increases exponentially with speed, conrods flex more. Lotsa things happen at high rpms.Lugging's bad too though. So there's that. When it comes down to it engines are either designed to run forever with low power output in which case they probably don't rev high enough to be asking much of the materials.

Doesn't really matter how you use it.For high strung engines you're damned either way. It's going to need a rebuild eventually regardless of how you treat it. Bouncing off the rev limiter is going to hasten its demise of course but they just won't go forever. Everyone seems to 'complain' that you allways should keep your RPMs as low as possible (shift early), and never drive so fast that you go past 3000 RPM with a TDI engine that has a rev-limit at about 5000.This isn't necessarily true. When you are at low rpms you must use more throttle to achieve the same acceleration. This increases the LOAD on your engine and internal components. Kinda like starting in a high gear on a bicycle, you might be pedaling slower, theoretically saving your knee joints, but you are pedaling harder.

Which is worse for your knees?You need to balance your rpms, load etc. Don't worry about revving up to 4k rpm, but there is no need to make it a habit. There is no need to accelerate slow either, your car is actually more efficient if you accelerate moderately.fyi, my 4 cylinder cruises at well over 3000 rpm at 70 mph, and I regularly drove on the highway at 80 mph (closer to 3500 rpm iirc). Short answer, yes. The more RPM's your turning the more movement your engine and it's internals are enduring. One hour at 4000 RPM twice as much movement as one hour at 2000 RPM.

Like saying driving an hour at 70MPH as opposed to an hour at 35MPH. Your tires traveled twice as far and therefor will have twice the wear. High RPM get much worse nearing max RPM. Max RPM is the limit that the engine can take before severe damage. Running at or near max RPM for extended periods will drastically reduce engine life.

Engines are usually more efficient at lower RPM as well. So early shifting etc will increase your gas milage. I have to disagree (in part) with that; your example of 'twice the speed- twice the wear' is a little faulty.

Z20let Bad Knock At 5k Rpm 2017

Per this thinking, driving one hour at 70mph and two hours at 35 would cause the same amount of wear (assuming the engine is in good shape and the rpm's are effectively doubled), but that is not true, because the forces in an engine are not always linear; they're exponential.Attach an object with a string around a stick so that the object can rotate around it and spin it at speed A, then double the speed; the force needed quadrupled. This is wrong.The load (when traveling at a constant speed) on the engine depends on the load on the car. Traveling at 5k rpm at 100 mph is MUCH harder on your car than traveling at 5k rpm at 50 mph. That is because you have to overcome air resistance, and that is a squared function. This means the air resistance acting on your car at 100mph is 4 times greater than at 50 mph.Edit: This doesn't necessarily mean that the wear on the engine would be 4 times greater, simply that the engine is working harder.