Effects of hard acceleration on a cold engine
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In my younger days, a few years ago, a couple of buddies and myself jumped into a rental (04?)Corolla in the dead of winter. To get some heat, buddy stood on the gas pedal and let it bounce off the rev limiter for about a full 1, 1.5 minutes "warming it up". I was cringing the entire time.... no two-stage limiter, it went from dead winter cold right to 6500 or whatever those things are limited to.
The brutality.
The brutality.
Now that I have a high performance engine with oil pressure and temp gauges, I pay a lot more attention to this. My V8 with 8 qt sump takes a while. Fully warm is 210F. But, with modern oils, I feel comfortable leaning on it at 150 but never redline until fully warmed up.
This is what I was thinking.
Avoiding putting the spurs to an engine when cold has nothing to do with the oil, assuming that a grade reasonable for ambients is used and everything to do with allowing the parts to gradually expand to their designed working clearances.
There is also some concern with old-school alloy head on iron block designs, since the head heats more rapidly than the cylinder block to begin with and alloy has about twice the coefficient of thermal expansion that iron does.
Running such an engine hard from cold on a regular basis could result in having to remove the head to replace the head gasket, not a fun exercise on most engines. The head will also probably need to be restored to flatness at the mating surface if it's removed.
I never run any engine beyond three thousand revs or more than half throttle when cold and I drive at least eight or so miles before puttling the lash to any engine, more in very cold weather.
I cringe when I see people get into a car that's sat for eight or nine hours and then zoom out of the parking lot, especially on a cold winter afternoon.
Avoiding putting the spurs to an engine when cold has nothing to do with the oil, assuming that a grade reasonable for ambients is used and everything to do with allowing the parts to gradually expand to their designed working clearances.
There is also some concern with old-school alloy head on iron block designs, since the head heats more rapidly than the cylinder block to begin with and alloy has about twice the coefficient of thermal expansion that iron does.
Running such an engine hard from cold on a regular basis could result in having to remove the head to replace the head gasket, not a fun exercise on most engines. The head will also probably need to be restored to flatness at the mating surface if it's removed.
I never run any engine beyond three thousand revs or more than half throttle when cold and I drive at least eight or so miles before puttling the lash to any engine, more in very cold weather.
I cringe when I see people get into a car that's sat for eight or nine hours and then zoom out of the parking lot, especially on a cold winter afternoon.
Just wanted to correct an oft-repeated myth in this thread.
The average new car owners are keeping their cars an average of six years, which is longer than ever before.
Used car owners are keeping their cars an average of more than four years, also a record.
They just don't build cars like they used to. And that's a good thing.
http://www.kbb.com/car-news/all-the-late...igh/2000007854/
The average new car owners are keeping their cars an average of six years, which is longer than ever before.
Used car owners are keeping their cars an average of more than four years, also a record.
They just don't build cars like they used to. And that's a good thing.
http://www.kbb.com/car-news/all-the-late...igh/2000007854/
Most of those “co-workers” will likely trade in/up long before things come unglued, regardless of their operating habits and ham-fisted use.
It’ll be subsequent owners that will get 150k instead of 200k from the transmission and 250k instead of 300k from the engine. Purely random speculation, of course.
I start out gingerly until things get to stabilized operating temperatures (per ATF temp gauge, etc.). Kinda sets the tone for a stress-free commute, too.
Make up for it by exercising through a few 1-2 and 2-3 WOT pulls each month to keep the “pistons cleaned.”
It’ll be subsequent owners that will get 150k instead of 200k from the transmission and 250k instead of 300k from the engine. Purely random speculation, of course.
I start out gingerly until things get to stabilized operating temperatures (per ATF temp gauge, etc.). Kinda sets the tone for a stress-free commute, too.
Make up for it by exercising through a few 1-2 and 2-3 WOT pulls each month to keep the “pistons cleaned.”
Originally Posted By: DBMaster
I concur about blind spots. I have just wondered about this for a long time. Heck, maybe I'll start doing it myself.
Yeah - the weird thing is in the truck I do it while in the car I don't. It's because I can more easily back into a space with the truck than forward park it.
I concur about blind spots. I have just wondered about this for a long time. Heck, maybe I'll start doing it myself.
Yeah - the weird thing is in the truck I do it while in the car I don't. It's because I can more easily back into a space with the truck than forward park it.
Originally Posted By: itguy08
Originally Posted By: DBMaster
I concur about blind spots. I have just wondered about this for a long time. Heck, maybe I'll start doing it myself.
Yeah - the weird thing is in the truck I do it while in the car I don't. It's because I can more easily back into a space with the truck than forward park it.
Hypermilers use this technique. Backing it in while the engine is warm is better than cold, plus when you go backwards you get 0 mpg. "Potential parking" is the most extreme where you find the high spot in the parking lot so you can get free coasting on the way out.
Originally Posted By: DBMaster
I concur about blind spots. I have just wondered about this for a long time. Heck, maybe I'll start doing it myself.
Yeah - the weird thing is in the truck I do it while in the car I don't. It's because I can more easily back into a space with the truck than forward park it.
Hypermilers use this technique. Backing it in while the engine is warm is better than cold, plus when you go backwards you get 0 mpg. "Potential parking" is the most extreme where you find the high spot in the parking lot so you can get free coasting on the way out.
I'm kinda old school myself and I don't run the defrost in the winter or the ac in the summer unless I have to(really hot car or windows really frosted. I also let it idle maybe a minute to 3 minutes depending on the temperature outside then I drive it kinda easy until the temp gauge is around a quarter up on the gauge. My wife on the other hand is a different story and I'll be switching her to Mobil 1 AFE from synpower. She just gets in and goes except for the winter time.
i warm up everything in the winter at least 5 full minutes and drive under 30 for about 3/4 of a mile in the summer i wait 2 minutes and drive slow.
if you put a listening device on an engine they are noisy when cold
if you put a listening device on an engine they are noisy when cold
In the summer, I walk to my truck, open the door, lean in, put the key in, start her up, stretch for a few seconds outside the trick (mind you, this is at like quarter to 7 in the morning, and I work a labor heavy summer job), hop in the truck, throw on my seatbelt, get comfortable, adjust the radio, and then I go. So, that's probably between 1-2 minutes of letting her warm-up.
In the winter, I trudge to my truck, hurry up and get the **** inside and close the door as fast as possible, ram the key in and start it up... and sit their shakin' in my boots, putting on my seatbelt, adjusting the radio... and then I get tired of waiting for it to warm up and just go.
When the outside temps are below freezing, and the windchill is in the negative teens (Fahrenheit, mind you), I have the mindset that I don't really care as much about letting it warm up, I just want the friggin heat now! Lmao!
edit: slightly related - one time when the windchill was like -20*F, when I started my truck up, it turned over and shuttered around 500rpms for 2 seconds and then rev'd up to the normal cold start range (~1500 to 1700 rpms?).
In the winter, I trudge to my truck, hurry up and get the **** inside and close the door as fast as possible, ram the key in and start it up... and sit their shakin' in my boots, putting on my seatbelt, adjusting the radio... and then I get tired of waiting for it to warm up and just go.
When the outside temps are below freezing, and the windchill is in the negative teens (Fahrenheit, mind you), I have the mindset that I don't really care as much about letting it warm up, I just want the friggin heat now! Lmao!
edit: slightly related - one time when the windchill was like -20*F, when I started my truck up, it turned over and shuttered around 500rpms for 2 seconds and then rev'd up to the normal cold start range (~1500 to 1700 rpms?).
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Hard acceleration on a cold engine may elevate wear because the piston is loose in the bore,the oil isn't up to operating temp and therefore will be less likely to properly coat cylinder bores,rings and so on.
Because everything is a bit loose there is more combustion bypassing the rings. The bearings won't be able to suck in the cold thick oil quickly enough.
Just spitballing
Because everything is a bit loose there is more combustion bypassing the rings. The bearings won't be able to suck in the cold thick oil quickly enough.
Just spitballing
Originally Posted By: jrustles
In my younger days, a few years ago, a couple of buddies and myself jumped into a rental (04?)Corolla in the dead of winter. To get some heat, buddy stood on the gas pedal and let it bounce off the rev limiter for about a full 1, 1.5 minutes "warming it up". I was cringing the entire time.... no two-stage limiter, it went from dead winter cold right to 6500 or whatever those things are limited to.
The brutality.
Wow, that's one way to get the heater working.
Poor rental cars.
In my younger days, a few years ago, a couple of buddies and myself jumped into a rental (04?)Corolla in the dead of winter. To get some heat, buddy stood on the gas pedal and let it bounce off the rev limiter for about a full 1, 1.5 minutes "warming it up". I was cringing the entire time.... no two-stage limiter, it went from dead winter cold right to 6500 or whatever those things are limited to.
The brutality.
Wow, that's one way to get the heater working.
One buddy had a 250r honda racing quad and a couple times it scuffed the piston with warming it up too fast from a cold start. The theory was that the piston was at full temp and size, but the cylinder wasn't yet. I guess it must've had too small clearances as well?
Never heard of a car doing this but I suppose if you just started one up at -30C and then jumped and stayed on the gas, you might be able to get the pistons at high temps before the block really warms up at all.
We never really wait for the car to warm up though, but we don't need more than 1/4 throttle for a 1/2 mile anyways.
Never heard of a car doing this but I suppose if you just started one up at -30C and then jumped and stayed on the gas, you might be able to get the pistons at high temps before the block really warms up at all.
We never really wait for the car to warm up though, but we don't need more than 1/4 throttle for a 1/2 mile anyways.
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