High RPM to Remove Carbon

This is Italian tune up:
Atlas oil temperature..webp
 
We got a junkyard ford 500 with super low miles owned by an elderly person. Carboned up, struggling and coughing and the power steering didnt work. I drove it like i stole it and the Power steering freed up and it ran great for 3 years while i beat it like a rented mule.
My stepfather had a mid 1990's 500SL which ran awful because of the constant low speed driving. I was afraid to do a hard run on the car because it was 20 yrs old at the time and I didn't want to get blamed for breaking something. Mom sold it and a year or so later the buyer stopped by my mother's house and said that the car ran great after taking it on to the highway for a good long run. Apparently he's now winning concurs events with it. I wish I could've bought it.
 
How long do you keep it at 4k rpms?
Not sure what is time that engine spends at 4k on its way to 7k rpm :ROFLMAO:

But when I ski, which is one or twice a week, I generally have no problems pushing oil temperature to 240-250f even though I have radiator oil cooler.
 
Two other benefits:
1. Get the intake valves nice and hot which helps break up that carbon.
2. Maximum airflow blowing through the intake. My basic calculations suggest that every 100 HP of output flows roughly 140 CF of air per minute. That's about twice what a powerful vacuum cleaner delivers.

In detail, assume 14.7 air-fuel ratio (by mass) and BSFC of 14 HP per gph.
At 100 HP:
  • 100 / 14 = 7.14 gph of fuel
  • 7.14 gph * 6 = 42.86 lbs. per hour of fuel
  • 42.86 * 14.7 = 630 lbs. per hour of air (air weighs 0.075 lbs. / cubic foot)
  • 630 / 0.075 = 8,400 CF of air per hour
  • That is per minute:
    • 0.714 lbs. of fuel
    • 140 CF of air
 
Not sure why anyone would think this worrisome or wonder about oil temps? Any modern engine should sustain 4k indefinitely.

I regularly flog my '11 6.2 harder than that for longer than that. Towing in Colorado, you have to.

If this is to be believed, any modern gasser that tows is clean as a whistle :D
 
This makes sense.

On my DI, non-turbo Honda, I've been babying it with 6 month OCI's (which usually equates to roughly 1k miles).
The oil is always clear with no fuel in the oil -using the scientific "sniffer" test. This engine is notorious for fuel dilution, so frequent changes are imperative to longevity.

Recently I took it up a local mountain road which has extended, straight 8% inclines, with a few long, sweeping switchbacks. Not only did I keep the RPM's up (only about 3500-4k), but kept the pedal pinned to the floor.

After only about 600 miles on this change, the oil color is substantially darker than it's ever been in my 4 years of ownership.
Moving forward, I'm going to follow this procedure before each oil change.
 
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Not sure why anyone would think this worrisome or wonder about oil temps? Any modern engine should sustain 4k indefinitely.

I regularly flog my '11 6.2 harder than that for longer than that. Towing in Colorado, you have to.

If this is to be believed, any modern gasser that tows is clean as a whistle :D
I agree. They can easily handle sustained 4k rpms. More wear on a cold start. The only thing sustained 4k rpms will do is heat the oil up more which will speed up the oxidation rate.
 
Not sure what is time that engine spends at 4k on its way to 7k rpm :ROFLMAO:

But when I ski, which is one or twice a week, I generally have no problems pushing oil temperature to 240-250f even though I have radiator oil cooler.
Don’t cause any avalanches cruising at 7000 RPM🤔
 
I can’t imagine driving my Corvette for that long at 4000rpm but maybe I will try doing a 30 minute run with the rpm at 3000 and see what kind of oil temperatures I see. I like the idea of possibly removing any IVD that might have formed in the last 106,700 km.
I would probably have to hold it in 5th gear at 70 mph in order to get the rpm at 3000, because 70mph in 8th gear is around 1300-1400 rpm.
 
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