Toyota Prius 2nd Gen. - converted to LPG hybrid

Hello,

I've just finished converting my Toyota Prius Executive 2007 into a LPG-hybrid. I name it formally "The three-hybrid", because it has 3 sources of power: gasoline, LPG and the HV battery. Would be nice to put a solar cell roof + the conversion to solar power, but I cannot afford those 3.500USD that I have to pay for that kit...:ranger:

I've used the products from attachment:
-STAG-300 Premium kit, made by Autogaz Poland (see http://www.ac.com.pl)
-Valtek-34 injector
-Tomasetto vaporizer
-STAKO LPG gas tank, has 34 liters (but only about 27-28 liters of gas can be put inside)
-OBD-II dynamic adaptation kit (it learns the driving style of the gasoline engine and translate the parameters to the one on LPG)
-USB diagnosis interface (with OBD-II code scan&clear tool for engine)

Regarding fuel prices in Romania:

LPG: 1L/0.26 gallons (liquid US)/0.21 gallons (UK) = 0.50EUR/0.40GBP/0.61USD
Gasoline: 1L/0.26 gallons (liquid US)/0.21 gallons (UK) = 1.11EUR/0.92GBP/1.39USD

The whole investment was 640EUR with shipping from Poland to Romania included. The weight was 22Kg/48lbs for gas tank and 12Kg/26lbs for the rest of the components, shipped with GLS courier.

Now, about the consumption... my LPG system starts to work when the engine reaches 15 degrees Celsius (after 2-3 seconds) and it consumes on this time some gasoline. Because of this, the gasoline tank manages to stay in my 45 liters tank about 4-5.000Km / 2.300-3.100 US/UK miles, while the consumption for LPG (including the one on gasoline) is:
-in Bucharest/city is around 6L/100Km = 47MPG(UK) = 39MPG(US) = 3EUR/100Km!!!
-outside city 5L/100Km = 56MPG(UK) = 47MPG(US) = 2.5EUR/100Km!!!

Enjoy the pictures and my documentation! BTW, my car is the 2nd LPG-hybrid from Romania... the first conversion was made by a friend of mine, Catalin (see both LPG-hybrids in a row, in one of the pictures). Probably he will write here something in closer future!:welcome:

Best regards,
Andrei from Romania

Re: Toyota Prius 2nd Gen. - converted to LPG bybrid

Marvellous! The kit, its documentation and your installation all look excellent. Please let us know your results over time.

Do you have a way to measure emissions?

Re: Toyota Prius 2nd Gen. - converted to LPG bybrid

That's pretty cool! Any danger of keeping petrol for such a long time in the tank without being used?

Re: Toyota Prius 2nd Gen. - converted to LPG bybrid

Hi Richard,

For sure I'll do this. Anyway, I forgot to tell people that me and Catalin (the other Prius-LPG-hybrid owner) very proud about our work. The car consumes about 5-10% more LPG than gasoline, but the LPG is more cheaper than the gasoline with 55% (after my calculations).

The investment (630EUR) is planned to be recovered in first 8.000Km/4.970miles..
Regarding the CO2 emissions, I have to go at Romanian Auto Register first, to register my modification to the car. I think the CO2 emissions will be divided with 2-3; if you put your nose on the back of the car you can even smell that air... (it goes water most of the time).

BR,
Andrei

Re: Toyota Prius 2nd Gen. - converted to LPG bybrid

Hi,

There's no problem with the tank, even if it's left without being used. It has about 3-4 protections if the LPG will get out (see that device from the middle of the LPG tank). I'm not very technical, but Catalin will tell you more when he will access the forum. I've just announce him to come...:rockon: he's a master in speed airplanes engines (he knows the airplane engine's mechanics very good and he's speed airplane pilot). Finally, he's got a US Army sticker put in the back of his 2004 Prius)!

Andrei

Re: Toyota Prius 2nd Gen. - converted to LPG bybrid

I meant with stale petrol/gasoline. If it takes you 4000-5000km to deplete a tank, it is sitting in there for 3 to 4 months.

Re: Toyota Prius 2nd Gen. - converted to LPG bybrid

Well, something like that.. But it's not a problem with the gasoline; it's just like letting a car in your garage with gasoline inside (will not expire, will not get vaporized and so on) .

I thought that you're asking me about the LPG that can get out from the tank after a while because of the high pressure inside. It cannot happen this (in my case it didn't), because the tank is fully secured and has some gas protections/valves.

BTW, I'm just curious, how accessible is the LPG in US? Do you have LPG stations? If yes, which is the price of the LPG?

Re: Toyota Prius 2nd Gen. - converted to LPG bybrid

Andrei, What a great write up, pics are pefect, well done!!! Please keep us updated on your MPG, KM/Liter results!

Re: Toyota Prius 2nd Gen. - converted to LPG bybrid

I'll do this for sure!:welcome:

As a matter of fact, in Romania they are around 22 million people and about 120 Prius cars sold by Toyota Romania, between 2006-present. The information is token from the Vehicle Producers and Importers Association (APIA - Asociatia Producatorilor si Importatorilor de Automobile), and this makes me very proud. You can see in Bucharest's traffic a Prius once a month, if you're lucky.. so this makes it an hybrid-exclusive car. The most owned car makers in Romania are: Dacia, VW, Renault, Peugeot, BMW and Audi. People prefer powerful cars, big engines and luxury. They cannot afford luxury to buy a brand new car, so they buy it from Germany at secondhand.

Re: Toyota Prius 2nd Gen. - converted to LPG bybrid

Re: Toyota Prius 2nd Gen. - converted to LPG bybrid

Interesting fact about gasoline, I didn't know. Good that you've told me this, I will make a small research about this tip..

Thanks for your praise!:thumb:

By the way, do you have LPG stations in US? Is it accessible for you the LPG? I don't know nothing about the US market, when it comes about this subject.

Re: Toyota Prius 2nd Gen. - converted to LPG bybrid

We have a very limited number of LPG stations nationwide. There is one 10 miles from my home. Our city government is building one for community use. Cost is less than gasoline but I'm unsure how that translates to miles traveled per unit.

You may use this unit converter, I'm very curious about the prices for LPG there in US.. http://www.digitaldutch.com/unitconverter/

Do you have also access to LPG kits there in US, or you'll have to buy them from Europe? Here, the LPG is very common everywhere, especially in Nordic countries. The main manufacturers and LPG car owners are in Italy and Poland.

What do you think about the LPG there in US? Which is the people's mentality there? Also, they are some Government deductions/taxes discounts, if you put LPG/alternative fuel on your car?

Re: Toyota Prius 2nd Gen. - converted to LPG bybrid

I just noticed that I've been responding to the LPG discussion and was thinking CNG (compressed natural gas) I hope I've not confused anyone.
Hey, it's been a long weekend

Re: Toyota Prius 2nd Gen. - converted to LPG bybrid

Yeah LPG is basically just propane (can have some butane as well) whereas natural gas is basically methane. Propane (and butane) can be kept in liquid form room temperaure with only a fairly modest amount of pressure. Not so for natural gas.

To mandrei83. Nice work. I see that you were able to fit the tank onto the spare tire bay. Where are you keeping the spare tire now?

Regarding the risk of your petrol going stale, I don't see any reason why you need to fill the tank. I'd just top it up to 1/3 of a tank every 1500km or something like that.

Re: Toyota Prius 2nd Gen. - converted to LPG bybrid

Hello,

The back-up wheel I'm keeping it in the back of the car, in same place where are kept the luggage. It's just put in a special case, at wheel's dimension, while the black plastic cover which is mounted between the luggage compartment and the back-up wheel was cut with about 5cm from height.

The gas tank has 180mm as height and it's quite higher, I couldn't close too well the luggage compartment because of it.

Regarding the petrol tank, indeed, there's no reason to keep it full, but mine is left full anyway, just to make a precise calculation of the operational cost, using my gasoline invoices. Probably I'll do this only first time, because I want to make this calculation mandatory...:rockon:

Andrei

Re: Toyota Prius 2nd Gen. - converted to LPG bybrid

It's threads like this that I really love this site.

I do like the conversion in the spare tyre well - out of the way leaving the boot/truck to be used still. We have lpg here and probably 1 in 3 garages sell it and it is almost half the price of petrol at 0.65p a litre instead of 1.13p for petrol.

I am in two minds whether to convert to lpg or install an enginer kit once my warranty expires, so I'll be watching for updates from Mandrei83 like a hawk.

Re: Toyota Prius 2nd Gen. - converted to LPG bybrid

Hello there!

Toyota warranty has nothing to do with this installation. I've spoke with Toyota Romania and they've told me that they will cancel my warranty only if the engine will have problems because of the LPG installation, I perfectly understand them.

If they cancel your warranty because of this (especially the one for hybrid system), you should send them to a law process and for sure you'll win!:rockon: It's a commercial right and they are too much things which can prove that the LPG kit installation has nothing to do with a fault on CD changer, MFD, electric system (lamps, hybrid converter, the HV battery and more).

Re: Toyota Prius 2nd Gen. - converted to LPG bybrid

Hi Andrei,

Thanks very much for posting your story and photos! I'm wondering whether you might provide captions or explanations for the photos, so that we can better understand what you're trying to show us.

Has the car's driveability been affected by this modification? Is power output of the drivetrain affected? Does the car sound any different?

I looked at the tech docs you posted, but it was unclear how the ECU which governs gasoline vs. LPG consumption interfaces with the Toyota hybrid system. It looks like you have considerable flexibility to adjust fuel/air mixture at various engine speeds? How do you decide what adjustments to make?

How about the MFD display that shows fuel consumption - how is that affected by this conversion?

Re: Toyota Prius 2nd Gen. - converted to LPG bybrid

No problem, Patrick, pleasure was mine also!
I want to make a tutorial in next weeks, but unfortunately I didn't had too much time until now. I'll enter on holiday this week and I'll do it in a day, with detailed explanations and pics.

I didn't feel anything modified badly. The drivetrain is not affected, the power delivered by the engine should be the same also. Note that my kit has dynamic OBD-II adaptation and learns the driving style of the petrol engine (see the circuit description from my first post).

It's connected to the OBD-II interface. Has nothing to do with the hybrid system, it's not connected to the hybrid engine's ECU.

Those parameters can be adjusted from the Windows software provided by Autogaz manufacturer (see description of it in my first post).

Doesn't show the real consumption, you have to calculate yourself the gasoline by taking as reference the bills. The consumption can be monitored only on that LED display provided in kit (has 5 bars, one of them is red).