Horses, Powerful

What is a HP (Horse Power, not to be confused with Hewlett Packard). A non-standard unit for measuring power. What is power. Something that creates mechanical work or heat, in general occurs when one form of energy is transformed into another, in a certain amount of time. Transformed in watts, which is a standard unit for measuring power (metric this time, not to be confused with SAE, or Standard American and English which is non-metric, confused already? Wait a minute, HP is SAE?).

"Well i never knew" there was a Horse Power and then there was a metric Horse Power, i don't have time for this right now, what i know is a HP is approximately 7 hundred something watts and this is what i want to talk about.

There is little concern in the US for like how many HP a car has. Some people look for things like, room, confort, safety. All these result in big cars, vans or SUVs and big cars need many HP to move and many HP mean usually big engines, V6 being midd range. Other people look for prices and smaller cars with smaller engines that are cheaper. Just googled and i saw the average power for a car in the US is 120 HP. That can't be right, from what i see on the streets.

Anyways. An internal combustion engine runs at a maximum efficiency of... Nevermind, i ran into something else. Google gives the answer for that question 80% which can't be true. Don't know how google picks the answer, next answer in line is closer to what i knew, 35-40% for "advanced engines".

But in reality, for real cars and real engines, with an average age of cars running on streets of 12 years, the real thermal efficiency of the engines is 20%. Which means 80% of the energy of the fuel is wasted in the radiator and exhaust. Heating the Universe as some would say. So it's the exact opposite of the answer picked by google to that question.

And here's where i wanted to get. Due to air drag, friction of tires with the road, an average size car needs about 15 HP on average to cruise at constant speed during long trips. The rest of the HPs, all the way to 120 or 200 or something is for acceleration. Usually you use for a few seconds all the power of the engine until you get "up to speed" and then you release the gas pedal and start cruising. From what i see on the instant dashboard indicator of the Elandra, engine goes to a consumption of 14-17 mpg for acceleration and above 35 for cruising. Hyundai Elantra indeed  has one of those advanced engines.

However, it's got a wasteful automatic transmission with hydraulic torque converter which is way more efficient at higher RPMs used during acceleration and wastes a lot during cruise. Waste in automatic transmission is so great it needs a whole section of the radiator just to cool it, in the range of 5 to 15%.

The newer continuous variable transmissions used in newer models (CVT) are much more efficient.

To compare that 15 HPs needed to cruise to the beach to let's say the energy used by a house, we need to transform the HPs into watts. 15 HPs by 750 would be about what, 10 KW, or the average power needed for 10 homes, including heating, dryer, AC, hot water, stove, other appliances. But when thinking that we use those 15HP coming from an internal combustion engine that has a 30 or even 20% efficiency, we realize that during those hours we use the energy needed to power up to 50 homes.

So that's why i'm tweaking the Hyundai almost every day, giving "them" opportunities to come outside and to their shows around me. Today it was raining and got wet and cold about 3 times (and they still started to move around me).

Because i saw one day i made from here to Spirit Mountain, a 49 miles trip, on other occasions, a mileage on the dashboard indicator of 39 mpg. But that was one day only. About half the times i get 37. It's not that much about the money, though a 15% difference in fuel consumption with that car would be about 1000 a year. It's curiosity and also pride. Hope i can prove something.

Then, every time something breaks allowing a vacuum leak. Last night coming back home it was 34. I replaced until now the hoses around the catch can i don't know how many times. Last time today, i found under one of the clamps a... hairline crack in the rubber hose? that was so straight it seemed a cut. I used high pressure, oil resistant breaded fuel lines. So i replaced them with PVC hoses. I modified the clamps, cause they were "gathering" the tire in one point or line and where not perfectly round.

I don't know why it's so important, but by freshly tightening those hoses, i get 15% better mileage. For that trip only. When i check the next day, i see they're loose again. The rubber gives in and then cracks. On the PCV ones, it looks like they get untightened. So i added extra nuts on the bolts.

The vacuum inside the intake while crusins is what, 15psi, but the problem is that is an average and it probably pulsates peaking at around 20 or something and probably the opening of the valves and sucking of the pistons gives shock waves through the hoses that combined with the movement (vibration) of the engine creates temporary pulsating leaks.

Original PCV hose (used without catch can) is preformed rubber, with spring clamps that barely tighten. I know Hyundai redesigned an engine with the shaft a bit off from under the pistons to make the angle at active stroke smaller just to get an increase of 1% efficiency when they are probably loosing for older or even newers cars up to 10% or more because of a hose and clamps.

I remember 15 years ago with the Nissan used mostly by Angela to go to work and for trips in weekends, i found a puncture in the heater hose, and i kept pouring coolant and coolant kept disappearing until i found that leak and went and fixed it. To me it looked a puncture made with a tool.

I don't know what to believe anymore.