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niky · 08-15-2011, 08:47 PM

If the kit is a venturi type, you can have it adjusted, old-school style, by tuning the flow, as on carburetor. You can look for adjustment tips online, I suppose. A lot of taxi drivers around here do it themselves. But it's suggested that you let an expert do this... preferably one with a wideband O2 sensor... as those same taxi drivers blow their engines by tuning too lean.

The problem with LPG is that it runs "drier" and hotter than gasoline... so on cars that rely on gasoline to cool down at high load (by running slightly rich), LPG may cause problems if you tune too close to the edge... tune too lean and the engine simply melts spark plugs. Tune way too lean and you're going to experience an epic meltdown.

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If it's electronic, they simply need to plug it into a laptop to do the same. Preferably at the shop that installed the unit.

I've some friends who get better economy on LPG after tuning... sometimes as good as or better than on gasoline... but this presupposes that your engine was poorly tuned on gasoline... in one case, one owner experienced a gain in economy because his fuel-injected Toyota van was at 10:1 (air-fuel ratio) at idle! This is far from the ideal 14:1 ratio! On an "economy" car like your Accent, finding an increase or parity in fuel consumption is unlikely... but possible. One Corolla owner sees the exact same economy as on gas.

My LPG unit is retuned to give me the same power as on gasoline (I still make more power on gasoline because we retuned the gasoline system after that with a piggyback controller). Fuel economy is still slightly worse (this is a modified engine on racing cams, can't expect much), but as said... the price difference really makes up for it.

08-15-2011, 08:47 PM	#5 (permalink)
niky Master EcoModder Join Date: Aug 2010 Location: Philippines Posts: 2,173 Thanks: 1,739 Thanked 589 Times in 401 Posts	If the kit is a venturi type, you can have it adjusted, old-school style, by tuning the flow, as on carburetor. You can look for adjustment tips online, I suppose. A lot of taxi drivers around here do it themselves. But it's suggested that you let an expert do this... preferably one with a wideband O2 sensor... as those same taxi drivers blow their engines by tuning too lean. The problem with LPG is that it runs "drier" and hotter than gasoline... so on cars that rely on gasoline to cool down at high load (by running slightly rich), LPG may cause problems if you tune too close to the edge... tune too lean and the engine simply melts spark plugs. Tune way too lean and you're going to experience an epic meltdown. --- If it's electronic, they simply need to plug it into a laptop to do the same. Preferably at the shop that installed the unit. I've some friends who get better economy on LPG after tuning... sometimes as good as or better than on gasoline... but this presupposes that your engine was poorly tuned on gasoline... in one case, one owner experienced a gain in economy because his fuel-injected Toyota van was at 10:1 (air-fuel ratio) at idle! This is far from the ideal 14:1 ratio! On an "economy" car like your Accent, finding an increase or parity in fuel consumption is unlikely... but possible. One Corolla owner sees the exact same economy as on gas. My LPG unit is retuned to give me the same power as on gasoline (I still make more power on gasoline because we retuned the gasoline system after that with a piggyback controller). Fuel economy is still slightly worse (this is a modified engine on racing cams, can't expect much), but as said... the price difference really makes up for it.