car facts or myths?

[Rhea26]

mga sir, patulong lang sana sa mga topics na to kong totoo o haka-haka lang (hehe), guidelines narin para sa mga newbies tulad ko, thanks!

1. nagccontribute sa fuel consumption ang aircon

2. mas malakas sa gas kapag nagbreak ka while on gear kesa kapag naka-neutral habang umaandar

3. mas matipid sa gas kung nasa higher gear ka, because you can cover more km with less hp kesa kapag nasa lower gear (while some say mas matipid kung mabagal ka lang)

4. mas malakas sa gas ang kotseng a/t kesa m/t

5. pareho lang ang effect ng over rev and under rev

[1997]

mga sir, patulong lang sana sa mga topics na to kong totoo o haka-haka lang (hehe), guidelines narin para sa mga newbies tulad ko, thanks!

1. nagccontribute sa fuel consumption ang aircon

Yes.. but opening your window sa Speed na 40Km/h above eh mas malakas sa Gas


2. mas malakas sa gas kapag nagbreak ka while on gear kesa kapag naka-neutral habang umaandar

Yes... Pero mas delikado kung mag break ka habang naka neutral or rolling down hill

3. mas matipid sa gas kung nasa higher gear ka, because you can cover more km with less hp kesa kapag nasa lower gear (while some say mas matipid kung mabagal ka lang)

For me I change gear sa 2000 rpm. Not necessary na kung mabagal ka eh mas matipid. Ang style ko is right gear sa right speed...

4. mas malakas sa gas ang kotseng a/t kesa m/t

Medjo

5. pareho lang ang effect ng over rev and under rev

Nope magkaiba ang effect... Under Rev hirap ang makina(underpower)... That is why yung Gear mo dapat nasa sakto sa speed mo.

Hindi ko sure kung tama lahat ng sinabi ko...

[meledson]

mga sir, patulong lang sana sa mga topics na to kong totoo o haka-haka lang (hehe), guidelines narin para sa mga newbies tulad ko, thanks!

1. nagccontribute sa fuel consumption ang aircon

2. mas malakas sa gas kapag nagbreak ka while on gear kesa kapag naka-neutral habang umaandar

3. mas matipid sa gas kung nasa higher gear ka, because you can cover more km with less hp kesa kapag nasa lower gear (while some say mas matipid kung mabagal ka lang)

4. mas malakas sa gas ang kotseng a/t kesa m/t

5. pareho lang ang effect ng over rev and under rev

1. Yes

2. Depende pero almost the same

3. with out lugging the engine, mas matipid kung nasa highest possible gear. more speed = more wind resistance then this means more gas.

4. Typically. pero kung rekta, puwedeng mas matipid ng konti ang A/T. depende sa gearing

5. No. Under rev is lugging the engine, over rev is red lining. Opposite ends of the tach.

[voltscastillo]

1. FACT
2. parang pareho lang eh. minimize coasting though, its unsafe pag matulin ka and the only thing stopping your car are brake pads and your foot.
3. FACT. given na ito. if this is not a fact then car manufacturers will only produce cars with 1 gear mas makkatipid pa sila.
4. FACT. but less so these days now na electronic na ang auto transmissions. yung malalakas sa gas yung mga 70s to early 80s na hydramatic a/ts.
5. what is over rev and under rev? high and low rev? if high and low rev and ibig mo sabihin then FACT na mas malakas sa gas pag higher rev. thats why we have 5 gears sa kotse, so you dont destroy your engine trying to reach 80kph at 1st gear on 5,500 rpm

[ghosthunter]

Feeling ko you don't watch Mythbusters? hehe

Most seems to have been answered in that show.

mga sir, patulong lang sana sa mga topics na to kong totoo o haka-haka lang (hehe), guidelines narin para sa mga newbies tulad ko, thanks!

1. nagccontribute sa fuel consumption ang aircon

In slower speeds, the use of A/C can increase fuel consumption.

But at higher speeds, the lower aerodynamic drag by having the windows closed offsets the added FC of the A/C.

BTW, this assumes a constant velocity, not stop & start driving we have in the city.

2. mas malakas sa gas kapag nagbreak ka while on gear kesa kapag naka-neutral habang umaandar

Generally it should be the same. The throttle is closed so no additional fuel is being burned by the engine.

3. mas matipid sa gas kung nasa higher gear ka, because you can cover more km with less hp kesa kapag nasa lower gear (while some say mas matipid kung mabagal ka lang)

Always the higher gear that will give you the highest speed at the lowest engine RPM (without lugging) will give you better fuel mileage.

But also aerodynamics play a role here. Maintaining a speed of 90 to 100kph maximum will give you the best balance of FC and speed/time.

But if you want to play the fuel maximizer game, drive at the highest gear at just over the engine's idle speed. I think most cars would be at 40 or 60kph.

4. mas malakas sa gas ang kotseng a/t kesa m/t

Traditional A/T consumes more fuel than M/T because the A/T absorbs more of the power from the engine.

Newer A/T designs like the CVT and dual-clutch A/T system (found in the Ford Focus TDCI DSG) gives the same or even better FC than the M/T equivalent.

5. pareho lang ang effect ng over rev and under rev

nope, they have different effects on the engine. I am assuming you are referring to wear & tear.

[Rhea26]

Mga sir, thanks sa mga replies! additional question lang, I change gears kasi based on speed and sa feel ko sa engine, not necessarily based on rpm, so I could use a higher gear agad to maximize fuel consumption, tingin ko naman kaya ng accord ko mgchange gears even before reaching 2000rpm and i don't feel na nahihirapan yung makina, anyway eto yung tendencies ko to change gears: 2 - 5 kph, 3 - 20 kph, 4 - 30 kph, and 5 - 40 kph, would you say na okay na to? or kahit hindi ko naffeel na nahihirapan yung engine, there could still be harm done sa makina? Thanks ulit!

[niky]

If it doesn't feel like it's lugging, it's okay. If it bucks like a horse, it's telling you you're going too slowly for the gear.

Best cruising speed is on a per car basis, but you usually get best economy around 2000-2500 rpm in the top gear on the highway.

[marvel67]

1) yes, the aircon contribute to the gas consumption, basically 3 to 5% but then studies showed that without aircon you open your windows, and the wind drag caused by the open window is also 3 to 5%, so patas lang po. I would rather use my aircon

2) engine braking tends to assist your brakes using the engine. It tends actually to push you engine RPM, thereby consuming more. But then for safety reasons, these are ideal for steep downhill driving.

3) In a way it true. But what is ideal and most economical is the right gear for the right speed. If you really want to be economical, avoid sudden stop and quick acceleration.

4) It all depends. Maybe in a heavy traffic, manual is more economical. But then if you're always cruising in a highway, the final gear ration of must a/t is better than manual, thereby using lower RPM on the final gear, and thereby consuming less gas than the higher final gear ratio M/T.

5) Actually no. But both are not good for your engine. Underreving your engine will cause strain on you conrod, conrod pins. Over revening will cause damage in your rings, camshaft, and accelerate wear. Both should be avoided.

I hope I have helped.

[Rhea26]

Opo, learned a lot actually, thanks!

[niky]

One thing to note:

When you're engine-braking.... which means, foot off the gas pedal, rpms are only being held up by the road speed... the throttle plate is closed. Which means no air is coming in. On most electronic injection engines, no fuel is being pumped into the engine, so you're using no fuel. Some will have a trickle going for emissions purposes, but that's it. If you're using more gas than by coasting, it's a tiny, tiny, tiny bit. And sometimes, you're using even less gas, because if you're coasting, the engine is using gas to maintain idle, whereas, if you're engine braking, on many cars the engine isn't using gas at all.