How bad is rev'ing up the engine?

Absolutely a big no no....actually kinda silly

Some engines/ cars have a limiting control to stop such sillyness

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Not until oil is warm generally, but others disagree on that as long as it has oil pressure.

 

Read the owners manual.

 

Both B and C. Modern cars have a fast idle control built into the ECM that provides a fast idle based upon the air temperature sensor. For the vintage V-12's, one has to monitor both the oil pressure and water temperatures gauges. I don't even move my car until the oil pressure gauge is all the way up and the temperature gauge moves off the peg. I keep the RPMs around 1000 with the throttle.

 

I really don't understand some of the responses .. OP said redline with cold engine .. that is crazy and plain stupid ..sorry

 

I once read that 90% of all engine wear occurs during the first few seconds of cold startup. Absolutely do not rev the engine before giving it time to build oil pressure and bathe the moving parts! And not over 4k until the oil is warm, per the owners manual

 

Its addressed in the owners manual. Has been in every Ferrari I have owned from a 1978 to a 2009....

 

“ Drive it like you stole it”
Remember hearing that quite often here 10 or so years ago.

 

You ought to pay attention to what has been said about the owners manual. Your quote ought to say “only idiots don’t read…”

 

What would your significant other say if you tried the same without proper warm-up?

 

Once the duct tape is removed I'm sure she would be upset ....

 

C - Not only does it make you look like an ass, it is detrimental to the engine- and not just for long life but stresses components immediately that can result in issues sooner rather than later.

I realize there are situations where someone wants you to blip the throttle to hear the car- and even some events encourage it (100 Ferraris descending on Children's Hospital for example) but make sure temps are up- and there's a difference between blipping the throttle so others can enjoy the sound and dry-revving like a moronic 16 year old with cherry bombs and the air cleaner upside down.

Cheers

 

"C" From a technical perspective this has to be one of the dumbest single things one can do to "ANY" engine.
When was the last time anyone witnessed a true race team start a race car and red line it cold..? There is a warm up process..
Yes its entertaining but very stupid which will hurt your pocket in the long run.

 

Supposedly OK for Lamborghinis or Mustangs....

 

I tend to believe that it's bad, but I don't know that through a basis on actual understanding of the engineering reasons as to why you shouldn't do that. Most of us are probably speculating that warmer oil can better coat all the components before revving at higher RPMs, but is that truly the case? And if so, how much time are we talking for oil to circulate? I'm thinking seconds given that the oil pressurizes as soon as the engine goes on. So does waiting 10 minutes or 10 seconds before you annoy your neighbors really matter? I won't do it, but I can't tell if it's out of superstition or mechanical reasoning. I'm not smart enough to know either way. I would love an explanation from someone who knows what they're talking about.

 

2 day ban for @daytonaman for attacking another member.

 

I would argue with this some as many areas are splash lubricated (and warm, thin oil splashes better than cold, thick oil), and, even on rotating/sliding joints that have a direct pressurized oil feed hole, the oil still has to flow out a relatively long distance in a very small annular clearance that can be smaller when cold. Take, for example, the valve shim buckets in a 308 -- the annular clearance to the cylinder head bore at room temperature is on the order of 30 um; whereas, this increase to about 50 um at operating temperature (because of the different materials). I will wager the farm that the force on the cam lobes to move the valve shim buckets at high speed when the clearance is small and the oil is thick is much higher than when the clearance has opened up and the oil has thinned -- i.e, damaging a cam lobe, or a cam bearing surface, is a likely failure at cold high RPM. Of course, a car that has been used recently would withstand instant high cold RPM better than one coming out of long disuse. Are you in a hurry?

 

Thank you Totto Bene, I got banned for criticizing someone who thought cold revving was OK.
Best way to break top rings as clearances are not yet up to operating spec.
Mod, cold revving is bad, end story

 

You were banned for calling another user an inappropriate name. We don't moderate for technical accuracy, just decency.

 

We need to clear this up.

Do not rev your engine until the oil is up to operating temperature. The water heats up in a few minutes but the engine oil takes 15 to 20 minutes to get up to a safe temperature. (Effect of Break-In and Operating Conditions on Piston Ring and Cylinder Bore Wear in SI (Spark-Ignition) Engines, Schneider et al). This research article shows how the wear is highest from the start-up time and only GRADUALLY decreases until the oil temperature is up to the normal level. It is not something that occurs in the first few seconds nor the first few minutes but rather for up to 20 minutes of driving.

More and more owners manuals tell us not to rev the engine until the OIL is fully warmed. Some manufacturers do not believe you have the moral strength to resist revving it up so they actually, electronically limit the RPM until the oil is warmed up. There are sound reasons for this.

There have been MANY cases where engine rebuilds were necessary in very low milage cars for this reason.

ali

 

Think we all knew from the onset that it wasn’t very wise.

 

1-don't do it
2-there is no beneficial reason for it
3-you look like a dork if you do it