Lpg on 1.8 turbo, which system?

[dissy1810]

i have a romano system in my non turbo which works well i also have a spare inlet manifold with the gas pipes in you can have if you want it as i changed mine to a vvc one

[Yella Fella]

What sort of cost is involved if a garage fitted a system?

[Bernard LPG]

Originally Posted by pianoman58

Bernard, How do you get the gas coming out of the evaporator ( which they all work on a "on demand" principle ) at very low pressure ( i've never measured it but it can only be a 1 or 2 psi ) to overcome the boost pressure in the inlet manifold which even in a low boost engine like a 1,8 k series is at least 7psi? When the engine is in a boost condition it needs a lot more gas, not less or none at all.
Unless you put the boost pressure into the back side of the diaphram in the evaporator in order to equalize the pressure in the manifold, but then, when you came off boost it would suck the diaphram backwards and again stop the gas flow, so you would have to have some sort of boost actuated solenoids to vent the back of the diaphram to atmostphere when not running in boost condition.
If you put a mixer plate before the turbo as with the old feedback system it would work, but if you ever got a backfire up the inlet, the resulting explosion would be spectacularly massive !!
Which make of system have you used on turbo engines

There has been a clear shift in technology since the system you are describing, Stephen. The modern systems supply vapour under pressure at typically say 1.0 bar above the manifold pressure. The flow of gas is then metered into the seperate inlet branches by a set of 'injectors' whose opening times are calculated from intercepts on the petrol injector feeds. There is no venturi in the system.

A small pipe is tapped into the manifold close to the throttle butterfly to provide a sense pressure to the diaphragm and also converted to an electrical level to give a reference to the gas ECU.

Therefore it does not matter what pressure the manifold is at, the pressure of the gas supply will always be at a set level above it. The ambient pressure has been taken out of the equation.

The metering of gas is very accurate and will meet the latest Euro pollution requirements, something the old venturi systems cannot meet.

To answer the question of the old venturi systems running a turbo, you are quite right in saying that a balance pipe is required behind the diaphragm. This will obviously follow the inlet pressure but it has no venturi and merely compensates for the pressure, but the feed pipe, being coupled to a venturi, will have the same pressure minus the depression created by the flow through venturi.
I can assure you that it worked well, but I was very glad when the multipoint systems were introduced about ten years ago.

As for the systems I have been using, I have learned the hard way to steer clear of the cheap end of the market, though I know that individuals have been happy with them. Equally, the top end of the market is over valued for what you get. So I have been very happy to fit systems from the AEB stable which are very easy to obtain spare parts and service for pretty well everywhere.

So systems such as OMVL, Zavoli and Romano are fairly ubiquitous and sit in the mid-market position.

Oh! and by the way, the Ford system was hopelessly unreliable and the supply company went out of business, leaving the systems high and dry. This did a lot of damage to the industry generally and is one source of the 'pub talk' which blights us, a bit similar to the 'Rover effect' I suppose.

[marinabrian]

Originally Posted by Bernard LPG

There has been a clear shift in technology since the system you are describing, Stephen. The modern systems supply vapour under pressure at typically say 1.0 bar above the manifold pressure. The flow of gas is then metered into the seperate inlet branches by a set of 'injectors' whose opening times are calculated from intercepts on the petrol injector feeds. There is no venturi in the system.

A small pipe is tapped into the manifold close to the throttle butterfly to provide a sense pressure to the diaphragm and also converted to an electrical level to give a reference to the gas ECU.

Therefore it does not matter what pressure the manifold is at, the pressure of the gas supply will always be at a set level above it. The ambient pressure has been taken out of the equation.

The metering of gas is very accurate and will meet the latest Euro pollution requirements, something the old venturi systems cannot meet.

To answer the question of the old venturi systems running a turbo, you are quite right in saying that a balance pipe is required behind the diaphragm. This will obviously follow the inlet pressure but it has no venturi and merely compensates for the pressure, but the feed pipe, being coupled to a venturi, will have the same pressure minus the depression created by the flow through venturi.
I can assure you that it worked well, but I was very glad when the multipoint systems were introduced about ten years ago.

As for the systems I have been using, I have learned the hard way to steer clear of the cheap end of the market, though I know that individuals have been happy with them. Equally, the top end of the market is over valued for what you get. So I have been very happy to fit systems from the AEB stable which are very easy to obtain spare parts and service for pretty well everywhere.

So systems such as OMVL, Zavoli and Romano are fairly ubiquitous and sit in the mid-market position.

Oh! and by the way, the Ford system was hopelessly unreliable and the supply company went out of business, leaving the systems high and dry. This did a lot of damage to the industry generally and is one source of the 'pub talk' which blights us, a bit similar to the 'Rover effect' I suppose.

Hi Bernard, I was thinking about a Tartarini Etagas 2 system, I was wondering if you've had any experience with this type of system, as my conversions so far have been limited to fairly simple mixer systems, with lambda feedback.
Many thanks
Brian.

[Bernard LPG]

Originally Posted by marinabrian

Hi Bernard, I was thinking about a Tartarini Etagas 2 system, I was wondering if you've had any experience with this type of system, as my conversions so far have been limited to fairly simple mixer systems, with lambda feedback.
Many thanks
Brian.

I used a lot of EtaGas 1 which was very good in it's day but rather expensive.
I moved away from the marque at the next generation because other systems had caught up in terms of technology and were cheaper, even when buying EtaGas directly from abroad.
So, the simple answer is no, nor do I see them out in the field, so to speak.
It is, I believe, still based on the AEB electronics, which is fine but I don't think that you will find much support for it out and about.

[marinabrian]

Thanks for that Bernard, I was thinking of this
http://cgi.ebay.co.uk/ws/eBayISAPI.d...T#ht_720wt_932
Obviously, I would be using a toroidal tank, new pipework etc, and Autogas 2000 in thirsk, would be my choice of installer for certifying the finished job, as they are tartarini agents, indeed I would say looking at the stickers on the ecu & 'vap, they probably had a hand in the supply of the original kit. I just didn't want to bid on this kit if it wasn't suitable.
Many thanks
Brian.

[Bernard LPG]

Originally Posted by marinabrian

Thanks for that Bernard, I was thinking of this
http://cgi.ebay.co.uk/ws/eBayISAPI.d...T#ht_720wt_932
Obviously, I would be using a toroidal tank, new pipework etc, and Autogas 2000 in thirsk, would be my choice of installer for certifying the finished job, as they are tartarini agents, indeed I would say looking at the stickers on the ecu & 'vap, they probably had a hand in the supply of the original kit. I just didn't want to bid on this kit if it wasn't suitable.
Many thanks
Brian.

Don't forget that you will also need the setting software and a computer interface adaptor and lead for it.