CNG Conversion Kits Look Similar, but are VERY different. Quality should always be the priority over price.
The recent fuel price dip hurt a lot of small “CNG guys”. We don’t like anyone to lose their job, but in the CNG world it can help the industry by weeding out those who can hurt the reputation of CNG. Watch out for those who go in and out of business trying to sell CNG equipment out of their garage or don’t do CNG installs very regularly. SkyCNG is a full time business. CNG is all we do. We actually drive CNG vehicles (surprisingly, some of the “suppliers” don’t!). We don’t sell used cars, real estate, or have some other job. Our products and services are unbeatable!
SkyCNG wants you to know there is a lot of bad information and bad hardware existing on the internet. Everyone loves to save money, but be careful what you consider. You may think you are saving a few hundred bucks, but in a few months you could be buying a new catalytic converter for more than $600… or worse… not to mention the fuel economy wasted and engine damage. Here are some things to watch out for and some questions you may want to ask another CNG conversion kit supplier.
Ask about these key factors of CNG Conversion Kits before buying:
Working pressure must be rated for 3600psi. You may have to read the fine print on this, as most are only for 3000psi since they are for foreign markets. Even many high quality Italian and Polish reducers are not meant for 3600psi. US standards for DOT approved cylinders/tanks require this CNG air pressure
Two pressure regulators “dual reg setup”- SkyCNG does not do a dual reg setup. Installers will do this setup to maintain good tuning on big V8 engines in the USA. The fact is you will still wear them out faster and likely be replacing in a couple years, you’ll pay a couple hundred dollars more in labor, there are more high pressure connections to worry about leaking, and the install is not very clean (it’s cumbersome!). Further, dual regs may hold a steady pressure on that big engine for awhile, but the fuel flow rate won’t be nearly as high as our SkyPRO-HD reducer. You need to ask specific details about their regulator/reducer. First, is it rated to 3600psi? Second, how many horsepower can it handle? Third, is it MULTI stage? Fourth, what is the output pressure? A good high performance injector works best with at least 2.5 bar pressure (about 45 psi).
SkyCNG has found that most reducers are rated to operate around 275 horsepower. While they can probably run on engines over 300 horsepower, the CNG regulator will start failing within a few thousand miles. Before it fails, the regulator will simply get inconsistent output pressure thus giving worse fuel trims and efficiency. This means you’re losing money and risking a check engine light.
The multi-stage SkyPRO regulator by SkyCNG is over 2 bar output pressure, it has upgraded springs from the similar “Tomasetto SUPER” brand and is rated to about 320 horsepower (not to mention our HD kit that can easily handle 8.0 liter engines!). SkyPRO flow rates are over 70 kg/hr and the SkyPRO-HD is over 150 kg/hr! Our customers are encouraged to get the SkyPRO-HD kit if the engine is over 5.0 liter and 300 HP. SkyCNG will let you know what’s best. Regardless, you should know that the regulator should look and feel like a “beefy” component. Cheap CNG regulators can be worn out quickly by even the smallest 4 cylinder car engine. Many sequential systems offer a SINGLE stage regulator. This is old technology and less expensive. The single stage cannot reduce the 3600psi fast enough to produce a steady output pressure for operating the injector rails. This is a key point when it comes to sequential systems. You must have steady output pressure for reliable performance. SkyCNG offers multi-stage reducers and HD reducers that give steady output at almost any engine load.
Many installers simply use the manual valve on a reducer to increase the output pressure so they can tune your engine. This is like increasing the voltage but not the current. All he is doing is reducing the lifetime of the reducer by wearing it out faster. In a matter of weeks or months it will not maintain steady output pressure and you’ll be losing mileage and performance. This is why SkyCNG has upgraded the springs inside the SkyPRO reducer to maintain steady 2 bar pressure for highest performance with big engines.
Don’t buy if:
The kit components visually look “mixed and matched”. Some sellers will get a reliable regulator, but the rest of the CNG kit is sourced from China or another lesser quality manufacturer. They obviously do this to save money.
The kit doesnt have English calibration software.
The kit doesnt have a complete list of components. Compare with SkyCNG.
The CNG conversion kit does not have a parts warranty. SkyCNG offers 5 (five) years.
They say their sequential kit will work on pre-1996 engines. OBD changed back then. The kit will not work. Always verify OBD II.
The seller claims the sequential kit is one size fits all. Sequential CNG injection kits are specific to the number of cylinders in the engine.
The seller tells you it is EPA certified without even knowing what kind of car you drive. Very few vehicles have an EPA certified system. So don’t buy the kit and expect to get government rebates/incentives (which don’t exist much these days anyway).