Coasting cunundrum

[JockoT]

My car has no air con. Wish it had.

[R.I.D.E.]

Then find a way to jam it in there in front of the radiator. It helps the engine warm up much faster and in 2.5 miles might cut the time to operating temp in half, especially with engine running constantly. If it restricts the air flow to much the electric cooling fan will come on. In that case make the block smaller.

I just ran my pipe insulation today, with two (of 3) brothers in the car on Interstate at 60-70 mph. After 35 miles the temp had climbed to 205 max, thermostat opening at 186. I removed a small section of the pipe insulation and it never hit 200 degrees, just about perfect.

Can't remember if it was Bentley or Alvis but Packard had the grille vanes that adjusted themselves based on temperature. Just like the 18 wheelers here you see with covers for the radiator.

Cooling systems are designed for "worst case scenarios". Many modern cars. have flaps that restrict air flow to the radiator. The principle is the radiator can remove to much heat from the engine, wasting fuel to heat the coolant when that same heat can be saved by making the coolant hotter coming out of the radiator (as it does in summer).

Temps here today were in the high 30s at sunrise, climbing to 57 degrees at peak. When I had to much blocked I just coasted down to lower speeds and the temps dropped quickly.

[SteveMak]

FYI, the poorer fuel economy due to cold weather is not just due to the engine needing more time to heat up. It also includes the entire drive train. It stiffens up due to the cold, and offers more resistance, and therefore, poorer fuel economy. This includes:

• belts and the devices the drive, like a power-steering pump (minimum effect)
• transmission (thickened up lubricant)
• universal joints
• differential(s)
• wheel bearings

One time that stayed overnight in the Virginia mountains on my way to Florida, the overnight weather was close to freezing. My vehicle got cold-soaked. The next day, even after an hour on the highway, my engine was still noticeably thirstier. Even when going downhill, where my fuel consumptions would normally drop to zero, the cruise control was still applying throttle to go downhill! By the time we were crossing the Georgia/Florida state line several hours later, ambient air temperature was in the mid-70s, and fuel economy on level roads was back to its normal high.

Yeah, cold-weather driving has a big negative effect on fuel economy. Everything stiffens up and offers more resistance.

[JockoT]

Today I was coasting down a steep hill. I was doing 40 mph when I slipped it into neutral, and it stayed at 40! This cold weather is really hitting my FE.

[Chrismag]

Hey man issued resolved as its an old post but I am in same situation, let me know if you there I live in lorton va.

[JockoT]

I still mix and match coasting in gear and coasting in neutral, depending on conditions. ScanGauge E is a brilliant tool for seeing how the mpg is going, both instantaneous and average.

[Draigflag]

Some new EVs actually allow you to turn of regen braking now, in certain circumstances, a car will travel further without motor regen/engine braking, which is more efficient. It's worth experimenting and finding what works best. I've said many times on this forum, theres a large hill close to where I live and you can travel up to 6 miles in neutral, that has to be more effective than in gear coasting.

[LDB]

Even with a small wife that could be a 5% or so difference in weight in your small car so noticeable.

[OliverGT]

Originally Posted by Draigflag

...I've said many times on this forum, theres a large hill close to where I live and you can travel up to 6 miles in neutral, that has to be more effective than in gear coasting.

I take it the car will slow down if you put it in gear?

There are a several, short, hills that I travel on regularly and there are certain points where you can be in gear and certain points where you have to be in neutral.

So it's just a case of trying things out and using the method that works best for the hill in question. For me, if you can stay in gear without losing speed, then stay in gear, otherwise in to neutral.

[Draigflag]

I'd agree there, sometimes there's a long hill, a flat section, then another hill. In said cases, neutral is better because in gear, you loose too much momentum on the flat sections and require acceleration again, whereas in neutral, the lack of engine braking means you can confidently cruise straight over the flat, or even slight inclined parts. Trail and error like you say.