Why are short runs harmful?

the biggest detriment is water from condensation.
the engine doesn't get hot enough to burn off the water in the block and exhaust system.
water gets in the oil and tranny lube causing corrosion.

 

Think of a Ferrari like a women. They in most cases are not too happy with a "quickie". You gotta warm them up before you go all out, otherwise..well you know the rest.

 

if that holds true, it actually applies to every car

in principle, i dont see an enzo anything fundamentally different from a corrola

the other day my phd friend told me: you see, human really didn't advanced that much, an alien would see no great difference in technology between a rocket that put a man to the moon and a 100 BC doulbe-bang Chinese cracker that makes a 10-year-old smile.

 

And sludge.

 

It does apply to every car. The difference is your Ferrari has 11 quarts of oil and a cooling system designed for the space shuttle. That means it takes a lot longer to warm up to opperating temp than a Corrola.

 

Asked and answered. Did you not read post 2?

 

A 3 mile run loads the engine and oil up with the water (and acid) byproduct(s) of combustion

A 50 mile run gives the engine time to get up to temperature, and allow the water in the oil to slowly evaporate. It also give time from the anti-wear additives in the oil to get up to temperature and start working (this takes 190dF oil temperatures), and activates the acid neutralizers (calcium) of the oil.

Basically, you need to get the oil up to 200dF and hold it there fro 10 minutes for the bad things that happen inside the engine at startup to "go away".

 

Ferraris are made to run hard for long periods of time. Cars like Corollas are made to be run briefly, sit, then go again for a short drive or maybe a long drive. Its just a different design brief.

 

I have also read that our engines (valve train) was designed as a high revving engine and short low speed runs will lead to deposits on the valves and elsewhere. May be where that expression " took it up to blow the carbon off the valves" I do know that moisture is very harmful to Harley engines and short runs are not recommended. Needs time to heat up and evaporate out the moisture from oil and condensation build up from the previous run.

 

Its the combining-emulsifying-which occurs with the petroleum lubricants ALONG with reactivity with the sulphur byproducts of combustion AND content in the fuel(used to be in the 5-800ppm range), which becomes sulphuric acid.
As heat and resulting evap occurs, this molality/molarity corrosive cocktail essentially reduces drastically to an essentially insignificant byproduct-but is still why we change our lube oils as frequently as we all do... this is a gross oversimplification of the real chemistry going on in there in the crankcases...

 

I wish my car only took 11qts! I could probably afford to change the oil if it did.

 

Its the other way around.

A Ferrari is designed for an infrequent use life. I.E. belt driven cams and engine out service on older models, cheaper alloys with spotty electronics on newer models.
Some of this is inherant to the design. Parts moving at a higher RPM are under higher stress and thus will fail with extended use.

The way around this to have an overbuilt drivetrain with heavier parts. This adds wieght so it is very rarely done. Thats why cars with high RPM have very little torque relative to HP. Heavier drivetrain increases torque and lower RPM. The result is a less charasmatic engine.

A Corrola or Camry are designed to run extended use for many miles.

 

Years ago, there was a post where the poster said he regularly changed the oil, but when he dropped the pan in a 3XX the bottom of the pan was covered with a gross layer of water/moisture sludge. The oil drain plug is not at the absolute bottom of the oil pan so an oil change won't get all of that moisture laden oil-out. The cause was that he regularly operated the engine without fully heating it-up. There are a lot of chemical, etc arguments, but this oil pan picture was the most graphic. The moisture problem also adversely affects the engine an exhaust components. (my search could not find the post)
In my case, I have to move my car in and out of my garage on a regular basis, but I push it in and out and only start the engine if I will run it for more than 20 min.

 

Phil I hear you but I can tell you I've been driving Ferraris on the track for years. Thousands of track miles. No problems. I understand your point that they are going for things like lighter weight and probably just what they have there but my point is these cars aren't made to be turned on, drive 3 miles, turned off, sit an hour, drive 3 miles, etc and keep repeating...

 

You should always drive any car at least long enough to get oil temp up to 100c/212f to boil off any H2O in the engine; especially if it is a car you only drive infrequently.