LPG-powered engines vs Non-lpg powered engines

**li0nh3a12t** · May 4th, 2008 06:37 AM

hi tsikoteers, i was just wondering what is the difference, advantages, and disadvantages between the lpg cars and non lpg cars. which is better and efficient? thank you...

**userfriendly** · May 4th, 2008 08:30 AM

Difference of lpg cars are:

1. dual fuel, you can use lpg or gas
2. have 2 tanks one for gas and another for lpg
3. have 2 filler tubes. Lpg uses a different filler that is impossible to mix up with gas. Phtsically different.
4. have additional stuff in the engine bay. Venturi mixer for open and closed loop systems. Lpg injectors for sgi kits. Additional ecu for the lpg system, a cutoff valve for gas and another cutoff valve for lpg and a few more stuff.
5. are heavier due to the additional equipment
6. as safe as gasoline powered cars
7. has a switch that lets you choose which fuel you want to use
8. open and closed loop systems lose around 5 to 10% power at high rpms, near the red line. SGI kits no power loss

**li0nh3a12t** · May 4th, 2008 09:23 AM

a ok. thanks po ng madami. which is better po in terms of fuel efficiency, maintenance, and power?thanks po ulit...

**userfriendly** · May 4th, 2008 09:54 AM

Originally Posted by li0nh3a12t

a ok. thanks po ng madami. which is better po in terms of fuel efficiency, maintenance, and power?thanks po ulit...

fuel efficency is the same with sgi kits. with venturi type kits, you lose a little cant remember exactly how much but its more than made up by the cheap cost of fuel. With lpg, you save on cost of fuel so your cost/km is a lot lower. Around 40% with todays fuel prices. 49 peso vs 27.8 pesos.

maintenace wise its about the same too. with lpg you just need to clean your air filter more often. easy enough to do. additional maintenance is checkinh of the lpg kit and maybe draining of the tank or is it the lpg valve? Best wait for confirmation from some of the installers that frequent this board. They also claim that you can extend your oil change interval with lpg.

Power already answered in my previous post. see #8

**blueguy** · May 4th, 2008 10:02 AM

Di ba delikado? me nakausap ako na driver, nagkakasakit daw..how true?

Some of taxi drivers using LPG said na mahirap daw umakyat pag naka LPG....like here in Cebu going to Nivel Hills...umaayaw ang mga LPG taxis....

**userfriendly** · May 4th, 2008 10:19 AM

Originally Posted by blueguy

Di ba delikado? me nakausap ako na driver, nagkakasakit daw..how true?

Some of taxi drivers using LPG said na mahirap daw umakyat pag naka LPG....like here in Cebu going to Nivel Hills...umaayaw ang mga LPG taxis....

Taxi drivers are not the best source of information. Getting sick from lpg fumes is a myth. If this is true, then why dont we get sick from the lpg used in cooking? While cooking, the lpg is burnt in an open flame without an exhuast. At least in cars its combusted inside the engine and gases sent out by the exhuast pipe.

Taxis are almost never properly maintained plus taxi drivers love to mess around with the kits and the engines in search of better FC and higher profits. So they usually run their cars lean. This results in poor power, possible incomplete combustion and who knows what else.

Uphill lose of power, I dont know. Ask Ghost Hunter he owns several lpg powered cars. Lets say this is true, then just switch to gas for the climb, then go back to lpg after.

Please refer to the main lpg thread in the economy and fuel talk section. It contains a ton of information.

BTW, why is this in the Honda car talk section? This is probably better merged with the main lpg thread or at least moved to the proper forum.

**blueguy** · May 4th, 2008 10:30 AM

I am planning to buy a Honda kasi...at nakita ko tong thread na to....and since mahal ang gas ngayon...

had to ask those questions...anyway the thread doesn't say naman LPG for Hondas....so OK lang naman siguro to ask...and thanks for answering....

**userfriendly** · May 4th, 2008 12:22 PM

Just remember that if you buy brand new and convert, the dealer will most likely void the warranty for the engine. But still best to ask them to be sure.

**niky** · May 4th, 2008 02:12 PM

Originally Posted by userfriendly

Taxi drivers are not the best source of information. Getting sick from lpg fumes is a myth. If this is true, then why dont we get sick from the lpg used in cooking? While cooking, the lpg is burnt in an open flame without an exhuast. At least in cars its combusted inside the engine and gases sent out by the exhuast pipe.

Taxis are almost never properly maintained plus taxi drivers love to mess around with the kits and the engines in search of better FC and higher profits. So they usually run their cars lean. This results in poor power, possible incomplete combustion and who knows what else.

Uphill lose of power, I dont know. Ask Ghost Hunter he owns several lpg powered cars. Lets say this is true, then just switch to gas for the climb, then go back to lpg after.

Please refer to the main lpg thread in the economy and fuel talk section. It contains a ton of information.

BTW, why is this in the Honda car talk section? This is probably better merged with the main lpg thread or at least moved to the proper forum.

The uphill loss of power is actually easy to explain. Back in the 60's and 70's small-engined gasoline cars had a hard time going uphill. Carburators couldn't maintain the proper flow of fuel at full throttle at mid-rpms... simply put, it was hard to calibrate them for smooth power. Nowadays, people are used to the more sophisticated carburators and fuel injection systems that allow even a tiny 1.3 liter motor to pull... say... an Avanza full of passengers uphill.

But the cheapo cheapo venturi kits that are installed in many taxis are really very crude LPG carburators... thus, they make much less power and have poor fuel economy... they make modern engines perform like small bricks from the 60's and 70's. With a modern metered kit or SGi kit, performance should be nearly the same or just as good as a new gasoline engine.

**ghosthunter** · May 4th, 2008 11:09 PM

My corolla uses the same LPG kit as with taxi cabs yet I can zoom around the metro and up Antipolo or Tagaytay with no problems. I can drive up car park buildings (like Shangrila Mall) with no noticable loss of engine power.

My solution? I have my LPG kit tuned properly. No secrets beyond that.

Those taxi cabs complaining that auto-LPG results in the engine losing power is the result of the driver tinkering with the LPG kit to save more money on fuel.