Vectra 2.2 Direct

Post Reply
Message
Author
Stargazer.
New member
Posts: 3
Joined: Fri Feb 15, 2019 8:36 pm

Vectra 2.2 Direct

#1 Post by Stargazer. » Fri Feb 15, 2019 8:48 pm

Hi yer! I have a Vectra 2.2 petrol Direct injection engine been told by two LPG fitters of whom have been reliable in the past that this cat can not have a kit fitted the only kit for it is no longer available is this true as I have a hard time believing it!

Brian_H
Intermediate Member
Posts: 1278
Joined: Mon Jan 23, 2012 12:21 pm
Location: Milton Keynes

Re: Vectra 2.2 Direct

#2 Post by Brian_H » Sun Feb 17, 2019 12:26 am

If you look through a few of Simons posts (Username LPGC on here) he covers the problems with Direct injection engines. Very briefly the problem is you need a kit with a setup for your particular type of vehicle/engine as they generally use the petrol injectors to inject gas via some extra plumbing. His posts will go into much more detail, but the problem is a combination of cost factors, and if a suitable kit exists.

There is an alternative of using port injection but it comes with some drawbacks - again his posts cover this in far more detail (he might reply here giving more detail as well).

LPGC
Installer
Posts: 3447
Joined: Wed Sep 29, 2010 6:01 pm
Location: Yorkshire
Contact:

Re: Vectra 2.2 Direct

#3 Post by LPGC » Mon Feb 18, 2019 11:21 am

1. The most common type of DI conversion kit are very similar to the usual type port injection kits we fit on most vehicles, no extra plumbing, the only difference to the usual type port injection kits is the LPG ECU, one of the differences with the ECU is that DI ECUs allow some of the petrol injection pulses to still reach the petrol DI injectors so some petrol still flows through DI injectors to prevent them breaking due to overheating etc. Another difference is DI ECUs interpret petrol injection pulses very differently to port injection ECUs because DI petrol systems can pulse injectors many times per 4 stroke cycle instead of just once or twice per 4 stroke cycle, it has to add the length of all these short pulses (which may be of different pulse lengths and frequency of pulses and between pulses may differ) together, it also has to electrically emulate DI injectors (which have different electrical properties to port injectors).
Since DI systems use various electrical spec DI injectors (so need different electrical emulation, sometimes depending on model / engine code), have various ways of pulsing DI injectors (pulse frequency / pulse length so need to add up total pulse time in different ways) again depending on model / engine code and since DI injectors need various amounts of protection from overheating (maybe every 1 in 5 pulses reaches the DI injectors so the engine runs on 1/5th petrol even when switched to LPG or maybe a different fraction of pulses reach DI injectors)... DI LPG ECUs (or at least their firmware) has to suit the specific DI vehicle / engine application.

2. Kits that involve plumbing are less common, they put LPG into the engine through the petrol DI injectors... No LPG injectors fitted or necessary, no LPG pressure reducer / vaporiser, no electrical emulation of DI injectors or adding up of multiple injections per 4 stroke cycle (to arrive at a pulse time for other/LPG injectors) strictly necessary - because if LPG is fed to DI injectors at the same pressure as petrol is/was fed to DI injectors the engine and driver don't see much difference between the 2 fuels. Plumbing is obviously necessary to get LPG from the relatively low pressure LPG tank fed to petrol DI injectors at the much higher DI pressure. And then there needs to be some way of preventing petrol to LPG and/or LPG to petrol mixing at the lower pressure side of the system (back to the fuel tanks)... a bit of petrol getting into an LPG tank wouldn't be much of a problem on this type of system but a bit of LPG getting into a petrol tank would be a big problem (gas pressure in a petrol tank and it's low pressure rated plumbing), hence diversion valves etc as part of the plumbing.

I haven't asked suppliers/manufacturers about what's made for the 2.2DI Vectra recently, there did used to be type 1 systems around but supplier websites are saying POA / out of stock. I don't know if type 2 systems were/are made for the 2.2DI Vectra engine but type 2 systems are usually more expensive than type 1, type 1 DI ECU's are more expensive than usual port injection type ECUs. Good results can be had from both type systems but type 1 will always use a bit of petrol while running on LPG and to me seems a bit of a fudge... we can very accurately replicate precise fuelling and related aspects when fitting a port injection LPG system onto a port injection petrol engine to the point that the engine and driver see absolutely no difference when running on either fuel but the same cannot be said of fitting a port injection LPG system onto a DI petrol engine - The closest analogy would probably be like fitting a petrol carb or gas mixer onto a complicated port injection engine (and still having to pulse the petrol port injectors to provide a fraction of the fuelling), sure we can get away with that on many port injected engines because they're not very complicated and don't feature aspects such as Atkinson cycle but most DI engines feature such complicating factors by their very nature... not much point in making an engine DI unless it has some of the other complicating factors.
Full time LPG installer
Servicing / Diagnostics / Repairs to all systems / DIY conversion kits supplied with thorough tech support
Mid Yorkshire
2 miles A1, 8 miles M62,
http://www.Lpgc.co.uk
Twitter https://twitter.com/AutogasSimon
07816237240

Stargazer.
New member
Posts: 3
Joined: Fri Feb 15, 2019 8:36 pm

Re: Vectra 2.2 Direct

#4 Post by Stargazer. » Wed Feb 20, 2019 10:26 am

Thank you for taking the time and effort for your in detail reply I have found it a great help I am just waiting for Autogas to get back to me to see if they can get the right kit

LPGC
Installer
Posts: 3447
Joined: Wed Sep 29, 2010 6:01 pm
Location: Yorkshire
Contact:

Re: Vectra 2.2 Direct

#5 Post by LPGC » Wed Feb 20, 2019 11:45 am

Who is Autogas? I'm an installer so does that make me Autogas too? lol.
Full time LPG installer
Servicing / Diagnostics / Repairs to all systems / DIY conversion kits supplied with thorough tech support
Mid Yorkshire
2 miles A1, 8 miles M62,
http://www.Lpgc.co.uk
Twitter https://twitter.com/AutogasSimon
07816237240

Brian_H
Intermediate Member
Posts: 1278
Joined: Mon Jan 23, 2012 12:21 pm
Location: Milton Keynes

Re: Vectra 2.2 Direct

#6 Post by Brian_H » Wed Feb 20, 2019 10:44 pm

LPGC wrote:
Wed Feb 20, 2019 11:45 am
Who is Autogas? I'm an installer so does that make me Autogas too? lol.
Autogas (the same people behind the Shell branded supplier) have made some efforts to develop their own network of installers, though if you don't know about it that suggests they aren't doing a particually good job of getting the word out there!

https://autogaslimited.co.uk/how-to-convert-your-car

Fill out our enquiry form below and we will pass your details onto your local Autogas Approved Converter. The selected converter will contact you within two working days to find out a bit more about your vehicle, your needs, and to give you a quote.

Doesn't seem to be any way of finding who their installers actually are without contacting them, Not sure if its anything do with the uklpg approved installer setup or something separate again.

LPGC
Installer
Posts: 3447
Joined: Wed Sep 29, 2010 6:01 pm
Location: Yorkshire
Contact:

Re: Vectra 2.2 Direct

#7 Post by LPGC » Thu Feb 21, 2019 11:23 am

Ahh yes... The Shell branded supplier called Autogas, don't they still turn up at Shell forecourts in Calor delivery trucks?

Seen so many firms with as close a website name to just Autogas come and go I'd forgotten about that setup. Had a quick look at the website.. funny that their Twitter name is AutogasLpg (same name as a now disappeared but was well known slightly dodgy LPG parts supplier).

There are some good words on the website, LPG as well as EV vehicles allowed in city centres, converting taxis to LPG, etc, it promotes LPG well in that regard. But it also has a lot of the usual bs and ill advice we have become accustomed to from firms that have association with a certain trade body. I expect, as you probably do, that this list of installers will be the same as the list of trade body members - list of installers who didn't do much besides pay a small fee to be on that list... It's a list which draws little distinction between it's members and to me it seems installers that want to be on that list are happy having their skills, abilities and knowledge considered as just the same as everyone else on that list - for whatever reason (should beg a few questions). Expect most members would prefer to have my reputation but did not have that before they were members and will never get it after becoming members. Can't buy reputation so if you can't earn it why not join a list that kind of puts you on par with others on the list.

I still get work from Calor.
Full time LPG installer
Servicing / Diagnostics / Repairs to all systems / DIY conversion kits supplied with thorough tech support
Mid Yorkshire
2 miles A1, 8 miles M62,
http://www.Lpgc.co.uk
Twitter https://twitter.com/AutogasSimon
07816237240

Post Reply