Cold temp/short-distance/occasional driving techniques – for health & longevity

[Simon S]

I have this thing where I like to take what I’ve learned from studies in meteorology, physics, chemistry, carpentry, and mechanics and incorporate them into aspects of my livelihood. For instance, it was weird for me to read about hypermiling techniques after having developed my own, natural techniques. They were the same techniques.

The following are my cold-weather/short-trip/occasional-drive techniques.

3K+ rpms when driving around – irrespective of speed -
So first off – when taking motorcycles for short, “exercise” trips, a mechanic once turned me on to simply keeping engine rpms at highway-speed levels. Usually ~3.5Krpm – give or take. When the engine is at this speed, the alternator is sure to be charging an under-worked battery. At those rpms, given engine is warmed up to temp – coolant is flowing, etc. I feel these same principles apply to automotive systems. So if you have to make a trip across town, simply do so in second or third gear. The goal is to keep engine rpms at or around 3K, regardless of how fast or slow you are driving.

Minimum/optimal distance -
If you can minimize exposure to road salt – do so (I’ve been taking the bus mostly this winter).
Start car and wait ~20 seconds to establish oil pressure.
Drive softly and smoothly.
Drive for a time or distance that allows engine to reach full warmth, then drive for at least another 5 minutes.**


** the biggest reason I do this is an effort to keep the exhaust system dry. You frequently see cars with water dripping from exhaust. This is natural. While I haven’t read a lot on the topic – my thoughts are that once engine and exhaust are up to temperature: 1) less water is generated/expelled – and 2) the exhaust itself is hot enough to evaporate water from its system. Dry exhaust = longer-lasting exhaust.


Discuss. Input appreciated. I like this topic.

[jlevie]

Sounds about right to me, but you left out the part about more frequent oil/filter changes. If the car see's a lot of that type of driving oil changes need to no more than half the normal interval.

[VinniE30]

Good writeup, I think about these things a lot and already do most of them. I'm skeptical of "waiting ~20 seconds to establish oil pressure though" should be way less.

Here's another one. Try to occasionally use mechanical systems that don't normally get used. For example, if you have AC, in the winter it probably hasn't been used in many months. This and the cold weather could cause things like the compressor to seize up and not work come summer time. Same thing with something like the sunroof. When things sit in the same spot for long periods of time through cycles of hot, cold, moisture, dryness, etc they tend to seize up / get stuck in position.

[JGood]

Funny you mentioned reading about the obvious hypermiling techniques after developing your own. I did the same thing (I've driven 80-120 miles/day for the past 10 years, 300k+ miles, so I learned a thing or two about getting max MPG's). It's also fun to watch people around you doing the opposite things! I obviously don't do the stupid things, like tailgating trucks or slowing to a crawl a 1/4 mile back from a red traffic light, but some of the techniques like throttle control on hills and timing some traffic lights can really help.

I let my cars idle for 20+ seconds on cold starts, but no more then a minute or two. I keep RPM's and throttle load low until the engine is warmed up. I gradually increase the max RPM and throttle load that I let the car see, until it's fully warmed up.

It's important on some newer vehicles to fully warm them up on each drive in order to keep moisture out of the oil. The short 3-5 mile trips really kill some engines when the oil separator systems start to act up.

[roguetoaster]

As Vinnie said you absolutely must run your A/C and exercise the infrequently used (in winter at least) systems of your car in order to maintain shall we say operational readiness. Outside of that no burnouts until the car hits at least the 1/4 temperature mark, no bang shifting either, then it's off to the races if one so desires. Depending on the overnight conditions you may want to try to skip using your handbrake too as it can stick.

As for cosmetic car you should have done it before winter. I wire wheel and paint my rotor hats and the mating surface of the winter steelies; clean and redo any suspect areas of undercoating and try to get as much of the exhaust (manifold back and welds/flanges at the cat) painted as I can. As it is now parked outside I wash it the very first day after it has warmed from sub freezing and give the undercarriage three good rinses. I will also try to get it rewaxed once or twice in winter in a garage.

This will be this E30s very first winter staying outside in a state that has actual winter so wish it luck fighting the tin worm!

[Varinn]

It's nice to see people understanding that you don't need to idle your car for 20 minutes before driving in the winter. The engine warms up significantly faster under moderate load than it does idling in your driveway, and they seem to suck back way more fuel when under operating temp.

Also, I agree with the keeping rpm's a touch higher. I hate when passengers tell me I should not be cruising at 2500rpm, but should keep the engine at around 1200 instead. Apparently it's better on gas, and less wear on the engine to bog it around town at near idle speeds all day versus at mid rpm's where the engine runs efficiently.

[dnguyen1963]

** the biggest reason I do this is an effort to keep the exhaust system dry. You frequently see cars with water dripping from exhaust. This is natural. While I haven’t read a lot on the topic – my thoughts are that once engine and exhaust are up to temperature: 1) less water is generated/expelled – and 2) the exhaust itself is hot enough to evaporate water from its system. Dry exhaust = longer-lasting exhaust.


Discuss. Input appreciated. I like this topic.

You lost me here a bit...The catalytic converter will get to operating temperature very shortly after you drive the car and stay at that temp independent of the engine rpm. Water boils at 100C and I am sure the exhaust system will be way above that number (except for the muffler, but muffler is cheap) even if you drive the car at 1500 rpm. So, what is the scientific rationale for the benefit of driving >3k rpm? I can see the benefit of burning the carbon deposit on the spark plugs...maybe.

[roguetoaster]

You lost me here a bit...The catalytic converter will get to operating temperature very shortly after you drive the car and stay at that temp independent of the engine rpm. Water boils at 100C and I am sure the exhaust system will be way above that number (except for the muffler, but muffler is cheap) even if you drive the car at 1500 rpm. So, what is the scientific rationale for the benefit of driving >3k rpm? I can see the benefit of burning the carbon deposit on the spark plugs...maybe.

I think the idea is mainly to avoid short trips to prevent the interior of the exhaust from rusting.

[Simon S]

Good discussion guys. Thanks for chiming in.

Sounds about right to me, but you left out the part about more frequent oil/filter changes. If the car see's a lot of that type of driving oil changes need to no more than half the normal interval.

10-4 on that. I perform oil changes in October and March out of habit. Changing oil in the winter? Not so much fun..

Good writeup, I think about these things a lot and already do most of them. I'm skeptical of "waiting ~20 seconds to establish oil pressure though" should be way less.

Thanks - and 10-4 on the 20 seconds. Mostly that's an approximate/give-or-take thing. It still sucks driving around when you, the car, and the outside temps are cold-as-fuck.

Here's another one. Try to occasionally use mechanical systems that don't normally get used.

.. and 10-4 on that as well. Goes without saying. At least 8 times a year - "exercise" every feature is my general rule.. lol

I let my cars idle for 20+ seconds on cold starts, but no more then a minute or two. I keep RPM's and throttle load low until the engine is warmed up. I gradually increase the max RPM and throttle load that I let the car see, until it's fully warmed up.

:up:

The short 3-5 mile trips really kill some engines when the oil separator systems start to act up.

Fuckin' A mate. I feel a whole lot cooler getting some exercise and walking my ass for trips like that. Irrespective of weather and temperature..

As for cosmetic car you should have done it before winter..
This will be this E30s very first winter staying outside in a state that has actual winter so wish it luck fighting the tin worm!

Ha! I'm not even going to break down your response since it appears we could be brothers.. on numerous counts.

It's nice to see people understanding that you don't need to idle your car for 20 minutes before driving in the winter. The engine warms up significantly faster under moderate load than it does idling in your driveway, and they seem to suck back way more fuel when under operating temp.

Also, I agree with the keeping rpm's a touch higher. I hate when passengers tell me I should not be cruising at 2500rpm, but should keep the engine at around 1200 instead. Apparently it's better on gas, and less wear on the engine to bog it around town at near idle speeds all day versus at mid rpm's where the engine runs efficiently.

Cool cool - you are also brethren. The fucker/decision-maker boils down to how fuckin cold it is and the luxury of commuting your ass in a warm vehicle. For some, the luxury overcomes what is best for the longevity of the vehicle. Bottom line there..

It's nice to see people understanding that you don't need to idle your car for 20 minutes before driving in the winter. The engine warms up significantly faster under moderate load than it does idling in your driveway, and they seem to suck back way more fuel when under operating temp.

Also, I agree with the keeping rpm's a touch higher. I hate when passengers tell me I should not be cruising at 2500rpm, but should keep the engine at around 1200 instead. Apparently it's better on gas, and less wear on the engine to bog it around town at near idle speeds all day versus at mid rpm's where the engine runs efficiently.

Fuckin A mate. It's all about the VE.. whatever that is..

I think the idea is mainly to avoid short trips to prevent the interior of the exhaust from rusting.

bingo

[CHIF8008]

bravo. bravo mate