Vapour gas on v6 - experiences pls

[bajdas]

I am looking at having a vapour gas system installed in our VZ Commodore Acclaim wagon, 3.6 alloytec V6 motor, automatic, Oct 2005, currently 91,000km.

Currently priced at $4,200 in Adelaide, less govt rebate. This is with a large gas cylinder mounted on the drivers side in the rear of the wagon. That way I keep the spare tyre.

From what I have read, the vapour injector system seems to auto-cutover from petrol to gas & still utilises the original engine computer system.

Holdens do not recommend the fitment because the engine is not a gas motor & gas runs hotter. RAA will not provide information for the same reason.

I would appreciate gaining information from people who have had the conversion done & their experiences. Please include brand of gas system because I am hearing some issues with a specific brand.

Specifically, what is the risk to the motor that Holdens are worried about. Is it just the valve seats ? Or am I risking the pistons & head ?

Thanks in advance.

[poweredbycng]

Currently priced at $4,200 in Adelaide, less govt rebate. This is with a large gas cylinder mounted on the drivers side in the rear of the wagon. That way I keep the spare tyre.

You will find that the best (and neatest) option is to pay a little bit extra for a toroidal cylinder that fits into the spare wheel well under the rear cargo area. The spare tyre is thus relocated to the cargo area behind the driver's seat and is secured to the side of the vehicle with a bracket.

From what I have read, the vapour injector system seems to auto-cutover from petrol to gas & still utilises the original engine computer system.

SVI systems will start and run the engine on petrol until the engine coolant reaches a pre-set temperature (usually 30-40C). From there (if LPG is selected, of course) the gas computer will automatically change the fuel over to LPG. The changeover is unperceivable - the only way to know this has occurred is to take a peak at the fuel gauge LEDs. If the pressure in the gas cylinder is low, the gas computer will automatically change the fuel over to petrol - again this is unperceivable except for warning beeps.

Holdens do not recommend the fitment because the engine is not a gas motor & gas runs hotter. RAA will not provide information for the same reason.

This is a load of bullocks and is a scare tactic by Holden to win more buyers for their factory-backed gas option. The dual fuel Alloytec engine is exactly the same as any other Alloytec. If you are worried about the valve seats, get a Flash Lube drip kit installed.

I would appreciate gaining information from people who have had the conversion done & their experiences. Please include brand of gas system because I am hearing some issues with a specific brand.

We have an OMVL/SprintGas Dream XXI-N system in our VZ SV6 (Alloytec 190). It was installed at about 48,000km and has now covered over 70,000km with absolutely no problems or compromises. Recently it was taken for a retune and gas service (cost $90) - it has never been better. Fuel economy is around 13-14L/100km on LPG in the Perth suburbs (compared to 11.5-12.5L/100km on 98RON PULP) so the decrease in economy is very minimal. We still have the factory (platinum I think) spark plugs installed and they are performing perfectly so far. Power-wise, the best way to describe it would be like this: you wouldn't know what fuel you're burning without looking at the fuel gauge LEDs.

Regards,
Dave

[VZ05]

bajdas, I have the factory system made by BRC or someone like that, runs like a dream and costs bugger all.
I was told that they change the valves and seats over to compensate for the extra heat... It has 162,000km's on the clock with no dramas so far, I just place a small bottle of Flashlube in the fuel so it may get a bit of Upper Cyclinder lubricant in there (i think it's just for the peice of mind).
I'd reccomend the conversion with the vapour gas as the car run perfect and save buckets of money on fuel.

There is a fella with loads of experince out near Mile End who I get to service my LPG, could be worth having a chat to him??

[poweredbycng]

I was told that they change the valves and seats over to compensate for the extra heat...

While Holden say that, there's absolutely no evidence that proves it. Holden's workshop manuals have no part number next to "LPG valve seats" making me think that it's a cover-up. There are now many VZ taxis running in Perth with both factory and aftermarket LPG setups. It will be interesting to see how they get along because our VZ SV6 is running perfectly with the OMVL/SprintGas Dream XXI SVI system.

Regards,
Dave