CRD Performance have been installing most makes of LPG systems for over 15 years now and honestly believe that considering the development work we’ve been involved in and number of different kit makes we’ve tested, some good, some not so good, then our opinion on choosing the best make of system currently available should carry some credibility.
Most LPG installers tend to try several makes and then, for whatever their reasons choose one make they feel comfortable with, this may be due to the complexity of that kit and their technical ability. They then try to convince every potential customer, on every new enquiry, that their chosen make is the best one to have no matter what their vehicle.
Honda CR-Z SP I-VTEC IMA Hybrid Electric STAG LPG conversion
CRD Performance, as recognized fuel injection specialists for both petrol and diesel blend LPG and CNG, have their own in house rolling road dyno testing facility and are actively involved in LPG Diesel Blend development. Directly as a result of this development work we have been fortunate in being able to install, test and evaluate not just most manufacturers complete LPG systems but also most, if not all, the many different makes of the so critically important LPG injectors and LPG reducers.
Some branded LPG kit manufacturers (eg.Prins, BRC, Zavoli.) will only sell their systems to installers as a package, complete with their own brand of injectors and reducers as part of a front end kit.
We believe a better approach is to compare an LPG system to an Audio Sound System where different makes of separates make up the best reliability and sound quality. Sony for example may build the best amplifier, Technics the best Tuner and Mission by far the best speakers. Using this example Prins may build the best ECU but the best injectors might be the ones BRC build but the most reliable and highest power reducer could be manufactured by Zavoli.
Honda CR-Z SP I-VTEC IMA Hybrid Electric STAG LPG conversion
At the time of originally compiling this website about 3 years ago, we would have strongly favoured the BRC system as being our number one choice, closely followed by Prins and then Zavoli. Whilst in recent years the Italian and Dutch LPG manufacturers seem to have stood in developing their systems (excluding of course any recent direct injection systems) the Poles have made massive steps into making their systems the best performing, most reliable and technically the most advanced in the world.
If we had to choose today, just one make of LPG system, based on reliability, cost, suitability, performance, driveability and value for money (for ALL non direct injection types of vehicles) the unanimous choice from all at CRD Performance would without any doubt whatsoever be the AC. Stag system.
CRD Performance first used the AC. Stag brand during development of their LPG/CNG Diesel Blend system and it impressed us so much that we’ve made it our No.1 preferred choice for all current petrol to LPG conversions. This kit is awesome; it allows us to do things we’ve always wished for but not been able to do before.
Honda CR-Z SP I-VTEC IMA Hybrid Electric STAG LPG conversion
What helps even more, and gives us yet a further advantage over most other LPG installers is that Eddie Zyla, the owner of CRD Performance, was born in England to Polish parents but speaks both fluent English and Polish. Needless to say, with there being no language barrier we have no problem at all when needing technical assistance or to discuss any special software requirements.
Unlike some LPG system manufacturers, AC. Stag have produced their own ECU (electronic control unit) but then programmed it so it can be used with almost any make of LPG injectors or reducer type currently available. Stag also manufacture in house their own design LPG injectors and LPG reducer as well as complete wiring harnesses, pressure sensors, connectors, looms and switches, in fact just about any part required for an LPG system.
Honda Civic Type-R STAG LPG conversion
This new approach from Stag allows LPG installers to tailor make a full kit for their customers particular requirements based on vehicle type, available budget, life expectancy, reliability, performance requirement, installation quality, appearance and driveability.
By choosing cheaper components with a shorter life expectancy and fitting them quickly in the easiest and non-cosmetically pleasing way, overall vehicle performance and driveability may be compromised but the customer will get a quick and cheap installation.
Alternatively, the same Stag ECU control system can be installed by CRD Performance but using the best available and most suitable make injectors and reducer(s) to suit the performance requirement of the vehicle. The vehicle is road tested and diagnostically checked using a scan tool before installation and the customer advised of any current fault codes present or driveability concerns, if required, these could be properly diagnosed and rectified, at an additional cost of course.
Honda Civic Type-R STAG LPG conversion
The LPG injectors will be installed using correct size jets and manifold nozzles to ensure faultless driveability and performance, these will be installed in a cosmetically pleasing way ensuring all wiring is shortened where necessary and neatly loomed using black cloth tape. Final set up and calibration is carried out by a skilled fuel injection engineer using our rolling road where necessary to ensure the best possible performance is achieved followed by further on the road map refinement ensuring optimum driveability and performance.
The Stag AC LPG System has some unique features not present in most of its competitors systems and it’s our opinion that many of these are as a result of the Stag software engineering team’s reaction to their installer’s requests. No matter how perfectly designed an LPG system may seem to its makers the real test is when installers fit them to many makes of vehicles, all with different performance and driving style requirements.
Honda Civic Type-R STAG LPG conversion
It’s the advanced driveability features and proven reliability of the AC.Stag system that make it in our opinion the best LPG/CNG system currently available anywhere in the world. Without going into too much detail of all the Stag systems features we can summarise and say that whatever the engine capacity, number of cylinders, BHP or engine type, the Stag system is able to cope with it. No matter how awkward or difficult it proves to “Gas”, Stag can deal with it, be it naturally aspirated, (standard), Turbo Charged, Supercharged, Valvetronic or even a Wankel engine, the same Stag ECU fits all.
Recent software additions have included fuelling corrections using can-bus data from the vehicle’s OBD port and even automatic cancellation of specific OBD fault codes caused by the slight differences in combustion properties between petrol and LPG. Vehicles which normally require an additional Flashlube system to lubricate valves can now use Stag’s unique new petrol split fuelling option to further help minimise the risk of valve seat recession.
Unfortunately, due to the weak currency exchange rate between Poland and Western Europe, these kits are cheaper to buy in the UK than most of the kits manufactured in Holland or Italy and therefore very popular and often used by low cost budget non LPGA certified back street LPG installers. The Stag product range is huge but unfortunately, in an attempt to keep installation costs to a minimum, some installers still cut corners and often use the incorrect and cheaper readily available interchangeable parts for some installations.
AC. Stag permanently employs about 500 staff in Bialystok Poland and in peak demand times this often increases to about 850. Stag are by far Poland’s No1 LPG/CNG equipment manufacturer supplying over 75% of the domestic market. There are other well known Polish LPG system manufacturers whose names include LPG Tech, KME and Europe gas, to name just a few, these are also recognized as being very good and still technically miles ahead of, for example, BRC, Prins, Zavoli, OMVL, Romano, Bi Gas, Landi Renzo, stefanelli, Lovato, Necam and Koltec and Ecotech etc.
Honda CR-Z SP I-VTEC IMA Hybrid Electric LPG conversion on the rolling road.
Honda Civic Type-R GT I-VTEC LPG conversion on the rolling road.
Summary
What we are trying to say here is no matter what you’ve heard either on the forums or from a man in a pub about how good or bad Stag LPG systems really are, take no notice of them and make up your own minds after reading this.If you are serious about getting your vehicle converted, be it from petrol to LPG or diesel to LPG Diesel Blend, (and are in agreement with our prices) then make an appointment to come and see us. One of us will take you out in either the high performance Mitsubishi Evo X LPG (petrol) or Mitsubishi L200 LPG (diesel blend) and demonstrate to you the Stag LPG system in action after which we will be happy to answer any technical questions you may have.