WOT Driving and Engine Wear

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I recently started a post asking if an Italian Tune Up is really benefitial for a engine, I got answers from various people saying how hard you have to drive the car for it to be benefitial and to be called a ITU, but this reports were a little confusing for me because they went against my conception of engine wear relation to WOT driving for extended periods of time.

Originally Posted By: TinyVoices
3500rpms is nothing for a gas motor. My mr2 does 4k at 90 on the highway in 5th. Run it like that for hours at a time. No complaints. I'd say more like 5000rpms for 20 minutes is more like it
Originally Posted By: StevieC
I should also add. I regularly red-line it on the highway at least once a week a few times when passing etc. followed by hi-revs engine braking to reduce speed back to the limit and I have done this with all my vehicles and they have all lasted the test of time and pass smog tests with original catalytic converters etc. I also don't use Top-Tier fuel any longer, just a quality fuel system cleaner just before an oil change.
Originally Posted By: LaCocina27
How long and how fast are key.

I was averaging about 115MPH in Upstate NY in regions so remote no radio stations came in. For a long time. THEN did normal speed moves with fast (90-ish, about normal for Upstate NY) and hard driving for two hours or so.

Never redlined except for short periods of time on hard acceleration.

You could really get on it for about a half hour AFTER FULLY WARMED UP and achieve an ITU. Maybe a little bit longer. A fast, LONG highway drive could achieve the same.


Doesn´t this kind of engine load for extended periods of time causes premature engine wear?
Can normal passengers vehicles take this abuse and still last 300k miles at least?
How long engine last for the car enthusiast that do thousands of miles on canyon drives and track days?
 
Answers are unknowable without saying exactly what engine and the maintenance expectations.

For example an RX7 engine and a LS7 are going to have different wear rates and time for rebuild.
 
I would look to what happens to race cars for guidance. When you operate machinery at its limits, it is more likely to break or wear out sooner than otherwise. Racing teams carry a lot of spare parts (including spare engines) for a reason. So when "experts" tell you to "beat the snot out of it," or drive it like you stole it," ignore them. If you elect to frequently drive your car hard, just be prepared for the consequences.
 
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Originally Posted By: Emanuel


Doesn´t this kind of engine load for extended periods of time causes premature engine wear?
Can normal passengers vehicles take this abuse and still last 300k miles at least?
How long engine last for the car enthusiast that do thousands of miles on canyon drives and track days?

The key in reduction of engine wear in high stress high rpm situations is to make sure the engine is up to full operating temperature. Not via the coolant, via the oil. How much if any extra wear is actually occurring is anyone's guess. I've read many of these threads and never saw any factual information proving occasional WOT was harmful, beneficial, or benign to an engine. If it is running good, toss a bottle of FI cleaner at it every 10K miles or so and motor on. Many engines go hundreds of thousands of miles with no Italian tuneups or special treatment. I think an occasional blast onto the highway when the engine is warmed up can help. IMO it doesn't have to hit red line either, and it doesn't have to be held there that long.

Having said that running an engine constantly at WOT will shorten its life. Common sense dictates that, and a little knowledge of how an engine works helps too. Red line constantly on the first cold start of the day, or red line constantly when its cold will shorten its life.

Certain DI engines might benefit some from an Italian Tune up, maybe..........
 
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ITU can be good for some things, and bad for others. The worst thing you can do is redline a high-mileage engine that spent its whole life putting around at 2000 RPM or less. As the piston rings and cylinder wall wear together, a lip (or ridge) forms on the cylinder wall at the furthest point of the ring's travel. At high RPM, the rotating assembly may stretch so that the piston ring impacts the lip worn in an engine that has previously only seen low speeds.
 
It is an Italian tune up not a way to operate the vehicle day in and day out. At higher rpms the piston rings flutter in the groves freeing them up them and some of the carbon blows out the exhaust. I am of Italian Descent [ Mom born in Italy and dads parents born in Italy] I approve of Italian tune ups.
 
My saturns definitely needed them to keep the rings free. They also got carbon on the piston crowns that lead to knock and spark retard. Water decarb is a step further than ITUs IMO and even those were needed.

Newish Prii also seem to have piston ring problems. They never engine break, either, and the owners rarely get on it in an effort to save fuel.
 
I regularly redline my 4-banger in the Journey on the highway as I have done with other vehicles. They all last a very long time and have great UOA's
 
Extended driving at redline = increased chance something will break. You're at the limit of what the mechanical components can handle.

Winding out the gears with some high rpm engine braking once a month is still a good thing imo. As long as the oil is warmed up it's going to do it's job and protect the engine. The brief periods at max rpm are enough to free up sticky rings, blow out carbon, blow out the cats, burn off cylinder deposits, get the oil pressure up and move any bits of stuff that may be there into the sump for the filter to catch.

You also need to consider the maintenance history of the engine. If it was a malnourished sludged up 4 banger, I would be cautious about high rpm oil flow breaking something loose which could then cause a blockage somewhere else.

It's always a judgement call. If the engine is in decent running condition and properly warmed up there shouldn't be a problem.
 
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Originally Posted By: eljefino
... Newish Prii also seem to have piston ring problems. They never engine break, either, ...
The first statement there seems to be true, too often. The second is false.
 
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Q: Are frequent ITUs going to diminish the overall life expectancy of the average engine?
A: No one truly knows. Maybe yes, maybe no. But the chances you'll see an appreciable amount of reduction in engine life are minimal, assuming reasonable circumstances are in place (modern engine with redline protection; warmed up engine, etc.)

Q: Should you be worried about getting to 300K miles on the engine if you plan on doing frequent ITUs?
A: I reject your question on the grounds it assumes someone who will keep a car to 300K miles is also the type of driver which believes ITUs are necessary - that's a unicorn.

You may plan on keeping your vehicle to 300K, and you may really, really want to, but are you actually going to? Be honest!

I would posit the transmission will go teets up long before the engine will experience adverse affects from frequent ITUs, thus necessitating the "to heck with it!" moment when you just get rid of it and buy something else.

And for the record, I am a fan of ITUs. Not because I believe they hold some mythical ability to make things right where once they were wrong. No, I like them because I am immature and childish. I like to drive as fast the road conditions will allow (and sometimes beyond), and I like to do it often. More is better when it comes to RPMs, and my vehicles are NO stranger to the redline and its pre-programmed up-shift for the trans.

I go WOT every single day for one reason or another, and I do it through multiple gears. Will my car reach 300K miles? Probably not, and I say that as someone who maintains it as much or more than most gearheads. But then again, I'm putting 3500 miles a month on mine, so it just stands to reason the car itself will wear out well before 300K and require me to completely replace it.

YMMV obviously.
 
Overly worried about engine wear, when you should be more concerned about what is more likely to fail, the transmission.
 
Originally Posted By: SilverFusion2010
Extended driving at redline = increased chance something will break. You're at the limit of what the mechanical components can handle.

Winding out the gears with some high rpm engine braking once a month is still a good thing imo. As long as the oil is warmed up it's going to do it's job and protect the engine. The brief periods at max rpm are enough to free up sticky rings, blow out carbon, blow out the cats, burn off cylinder deposits, get the oil pressure up and move any bits of stuff that may be there into the sump for the filter to catch.

You also need to consider the maintenance history of the engine. If it was a malnourished sludged up 4 banger, I would be cautious about high rpm oil flow breaking something loose which could then cause a blockage somewhere else.

It's always a judgement call. If the engine is in decent running condition and properly warmed up there shouldn't be a problem.


I support this opinion.
 
I believe the ITU was more beneficial in the time of the carburetor. Babied cars from that era would put out lots of smoke when punched for the first time. I've never seen that from a FI car. I do believe periods of WOT are good for most cars. My 1997 4.6 F150 would see WOT daily and some times for 30-40 seconds continuously while pulling a car trailer. I sold it with 330,000 miles, and it still ran fine.
 
old police cars get the [censored] run out of them and then go on to be taxi's and then back to public, I have seen many with 400,000 miles on them running fine.
 
Originally Posted By: ShotGun429
old police cars get the [censored] run out of them and then go on to be taxi's and then back to public, I have seen many with 400,000 miles on them running fine.


I agree, run it fast and furious. Jake and Elwood Blues (the Blues Brothers) car was still running fine, out-ran most of the newer police cars.
 
Too many variables to consider::

Consider a previous generation F1 V8 engine.
When run as engineered, they were expected to last 10 hours.
If run like grandma going to church on sunday, they would not last 20 minutes.
These engines were designed to run between 7,000 and 17,000 and idle at 4,000.
These engines ALSO had to be up at operating temperatures before turning the crank over or you would spin a bearing.
So any references to racing engines and passenger engines is not relevant to the question posed.

Also consider:: when an engine is run really hard for a considerable amount of time, the oil reaches a significantly higher temperature than when the engine is driving around town.
Doing an ITU with 200ºF oil is going to be different than doing an ITU with 280ºF oil--independent of what oil is being used.
 
Originally Posted By: ShotGun429
old police cars get the [censored] run out of them and then go on to be taxi's and then back to public, I have seen many with 400,000 miles on them running fine.


Did the WOT driving extend their life? Or, was it lack of thermal cycling (no cold starts) and a dedicated maintenance department funded by tax dollars (that likely ignored repair costs)?
 
"Go blow the carbon out of 'er!!"

Today's engine burn so clean, nothing more is need than good fuel and good oil. that's it.
 
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