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Generation 3
Explained
The arrival in the market place of the
Generation 3 systems, is
the
most important development in Autogas conversion since the Lambda
sensor was used to monitor emissions.
Vehicle manufacturers have
developed the 4 stroke engine to levels of cleanness and performance only
dreamed of a few years ago. From the start of 2001 all vehicles on the road must
have engines that comply with a standard called Euro 3. In addition legislation
has been passed in the European Parliament for a method of continuously
monitoring the exhaust gas emissions. This system is called E.O.B.D. It stands
for European On Board Diagnosis. If your car has been registered since the start
of that year it has it. One of the aims of this equipment is to monitor the exhaust
gases after they have been through the catalytic converter to ensure that they
are clean enough. If the emissions are incorrect or another fault is found a warning light will flag up on
the dash to telling the driver they have a problem. You must then have the fault
rectified immediately. If you are subsequently stopped by one of the enforcement
agencies, they are in theory able to interrogate your on board computer and find out
how long the fault has been there. It will not be possible to tell them that it
came on ten minutes before if it didn't. Large fines, and other terrible
punishments have been promised (flogging, ritual dis-embowling etc) to any
transgressors.
The effect this has on
any Autogas conversion is that it must meet the emissions required and work with
the cars computer to ensure the light stays off. To do this the system used must
be extremely sophisticated. Enter Generation 3 equipment !!
By fitting gas injectors close to the inlet valves the problem of
having an explosive gas mix in the manifold is almost completely eradicated,
meaning that back fire problems are eliminated. The fact that
the gas inlet is much closer to the engine than on the previous generations
means that the engine responds much more quickly, and as the fuel is a gas
the combustion is more complete than with petrol.
The description that follows is as basic as I can make it, but I have had to
assume that you, the reader possesses some mechanical knowledge. However if it
doesn't make sense contact me and all will be revealed.
The back end kit is identical to earlier systems, and indeed the
vaporizer under the bonnet is very similar apart from being non-adjustable and having a
vacuum pipe running between it and the inlet manifold to ensure that the correct
pressure differential is maintained in all circumstances.
The gas flows from the vaporizer
to the distribution unit where the volume of gas
injected into the inlet manifold is controlled. Each injector receives a signal
via the main vehicle computer and the dedicated Autogas ECU so that the correct
amount of gas is injected at precisely the right time.
Because the e.c.u. is much more sophisticated than on Generation 2 systems it
is possible to control the fuelling more accurately than would have been thought
possible only a few years ago. This means that the vehicle should have virtually
no discernable power loss in normal circumstances, and fuel consumption
more comparable to running on petrol. The
environmental benefits being an even greater reduction in pollution of our
atmosphere.
The vehicle defaults to petrol on start up, but automatically changes to gas
when the engine is revved and the temperature of the vaporizer exceeds 30
degrees C. When the vehicle runs low on gas the e.c.u. detects that the air/fuel
mixture is too lean and automatically switches back to petrol.
Inside the vehicle the only tell tale sign is a small combined fuel
gauge and
switch, which is mounted discreetly in the dashboard area. This is identical to
the earlier Tartarini systems and unfortunately the fuel gauge is not exactly
accurate. To be honest the things about as much use as a chocolate fire
guard. However as the rest of the system is superbly engineered, it
is a minor problem.
An SGI
system (Sequential Gas Injection) is
more expensive than the Tartarini Tech system (Gen 2). A typical 4 cylinder
non-turbo application will cost around £1750 plus vat. Six and eight cylinder
vehicles will be more. The pay back being the improved economy.
In addition a whole
range of vehicles which in the past could not be converted without serious
problems are now able to be taken on.
The development of SGI
is a major step forward once again. It uses the cars own management system to
trigger the gas injectors. Thereby refining even further the fuelling
requirements of the engine.
If you would like
more information please feel free to contact us. We are happy to
advise.
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