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  • Carburetor adapter and cone filter installed on carburetor. NOT INCLUDED
  • Top fittings are 3/4" and bottom are 1" fittings for 8 or 10 cylinder engines.
Left fittings are the standard fitting that comes with the kit.  The right fittings are optional and cost extra.
  • Image 3

CNG Conversion Kit For 8 Cylinder Carburetor Gasoline Engines Model CNGC8


 Product Description

CNG Conversion Kit for 8 Cylinder Carburetor Engines
Model CNGC8
Comes with a new Super Output Regulator and a 1 year warranty.  New 1" fuel hose and stepper motor for more power.

Our carburetor kit converts your engine to a fuel injected engine while operating on CNG.
Please completely read all the information below before ordering.

We will need the following information about your vehicle when ordering a conversion kit:
1. Fill Nozzle Type (Read Fill Nozzle Options section below.)
2.  Mixer Size  (See the information below for more information on selecting the mixer size.)
3.  Year of Vehicle
4.  Make of Vehicle
5.  Model of Vehicle
6.  Number of Cylinders
7.  Engine Size in Liters
8.  Comments (Leave any additional information or comments you may have.)

Some engines that may require special parts from us or after market parts.
1.  Engines with duel carburetors will require our dual mixer kit.  The duel mixer kit comes with an additional mixer, a tee fitting, 18" of additional hose, and 4 additional hose clamps.
2.  Most carburetor engines will need a single port carburetor adapter or a cold air intake kit.  
These kits include 3" or 4" round tubing, couplers, clamps and a cone shaped air filter.  The air intake system will allow you to install the mixer in or to the round intake tube.   If installing the mixer with hose couplers, order the mixer the same size as the tubing.  We recommend installing or at least ordering the air intake system before ordering the CNG conversion kit so you know what size mier you will need.  These  parts are available at your local auto parts store or online. See the Spectre brand at most auto parts stores.

Fill Nozzle Options
We have two fill nozzle options.
1.  Standard fill nozzle with 1/4 turn shutoff valve with 2 ports so it can be installed in-line from the cylinder to the regulator.  This is what you should order unless you need one of the other options.
2.  Strait nozzle without shutoff valve.  For installing in tight or hard to get to locations.  Comes with an extra 1/2 length roll of tubing.  It is connected directly to the tank valve.  The regulator is connected directly to the other port of the tank valve.  

Stainless Steel Fittings Option
For a small additional cost we can supply 1/4" or 3/8" stainless steel fittings so you can install stainless steel tubing instead of the steel tubing that comes with our kits.  We do not supply the stainless steel tubing.  We recommend our steel tubing as it is lower in cost and much easier to install.  Call to order if desired.

How the Carburetor Conversion Kit Works 
A mixer (venturi) is installed in the air intake between the air filter and the carburetor which provides single point fuel injection.  If your air filter is mounted over the carburetor you will need to order a carburetor adapter to convert to a 3" or 4" round tube to mount the mixer in or to.  You will also need and a cone shaped air filter, tubing coupling, and perhaps other parts, or a complete intake kit designed for your vehicle.  An oxygen sensor installed on the engine's exhaust is monitored by the CNG controller which controls an electronic valve (stepper motor) installed on the low pressure CNG fuel hose going to the air intake to provide the proper fuel ratio at all times.  Do not purchase a conversion kit for a carburetor engine that does not use an oxygen sensor and a feedback controller.  On all gasoline engines the combustion air has always been controlled with a throttle plate so it makes sense to bring the fuel in with the air letting the oxygen sensor that comes with the kit adjust the fuel ratio.  This provides the best mixing of the gas and air which provides excellent engine performance.  The engine idles and runs the same as it does on gasoline.  The timing is advanced for the best operation on both fuels by rotating the distributor.  The 3 way switch on the dash allows you to convert to either fuel.  When converting to CNG you place the switch in the neutral position which shuts off the gasoline to the carburetor with the provided solenoid installed on the gasoline fuel line.  When the gasoline begins to run out the switch is changed to the CNG mode.  The instructions are written for the car owner to install with many tips, "how to" information and a trouble guide.  A computer cable comes with the kit and programming is simple and takes only a few minutes.  The software is downloaded from our web site.  Our controller features self adjusting electronics which always provides peak performance.  The control on the dash indicates which fuel you are using and how much CNG is in your CNG tank.  This kit allows you to run on either gasoline or CNG with the push of a button on the dash.  If you run out of CNG you will begin to loose power so you just push the button on the dash and you will switch to gasoline and continue driving.  You should always refuel before you run out of either fuel.  See our web site for more information.

All of our kits have a control on the dash which indicates which fuel you are using and how much CNG is in your tank.
All of our kits allow you to run on either gasoline or CNG with the push of a button on the dash.
All of our kits come with regulators designed for your engine size for more power and better performance.
Our Millennium kit will automatically switch to gasoline if you run out of CNG.  You should always refuel before you run out of either fuel. 
We design all of our kits ourselves, and we manufacturer some of the parts.  Some of our parts are imported from other countries.  Some parts are built in the USA. 
We have chosen the best parts with the best prices to provide the best kits available at the best price. 
All our kits are rated for 3,600 psi and come complete with everything you need including the filling nozzle.  CNG storage tanks, tank valves, and mounting brackets are sold separately. You can use any type of legal DOT certified CNG tanks with our kits. 

More Information about our CNG and LP Conversion Kits

Mixer Kits
Mixer kits are known as mixer, aspirated, fogger, single point injection, or air intake conversion kits.  We have mixer kits for all engines including fuel injected, carburetor, and diesel.  These kits are the easiest to install and adjust and are the lowest cost. 

Millennuim Kit
Above is a picture  of our Millennium kit.   

Compressed Natural Gas (CNG) is one of the lowest cost and environment friendly alternative fuels available. More than 12 million cars in the world are driving on CNG. All you need is a CNG Conversion Kit, a CNG Tank with Valve and a Mounting Bracket for the Tank.
You can use multiple tanks for a longer driving range with any of our conversion kits.

Why CNG?
OIL FREE - Natural Gas is Produced in the USA
SAVE - Costs up to 80% Less than Gasoline
CLEAN - Fewer Emissions Save the Environment
SAFE - CNG Kits and Tanks Built to ISO or DOT Safety Standards
EASY - Filling Your Car is Nearly as Fast and Easy
CONVENIENT - Bi-Fuel System - Change to Gasoline or CNG with the Flip of a Switch Even While Driving

Lowest Cost Fuel - As low as $.88 a GGE (Gasoline Gallon Equivalent). If your car gets 30 mpg on gasoline you will still get the same 30 mpg on CNG and at a lower cost. That is like going from 30 mpg to 90 mpg if you are spending 1/3 the cost for CNG. In many areas the cost of natural gas is regulated, keeping the price low.
Domestic Fuel - Not dependent on foreign oil and their constant price increases. You will save even more in the future as gasoline continues to rise faster than natural gas.
Environmentally Friendly - Fewer emissions as hydrocarbons are virtually eliminated.
Engine Runs Cleaner and Lasts Longer - No Carbon Deposits Which Create Friction and Engine Wear.
Ignition (Spark) Plugs Stay Cleaner and Last Longer - No carbon deposits to clog and dirty the plugs.
Bi-Fuel - Change to either fuel with the push of a button.

Reduced Performance - With our conversion kits for gasoline engines performance is reduced by approximately 10 to 20% as natural gas has different physical attributes, and your engine was designed to run on gasoline. The mixer also restricts air flow.
Storage Space for Storage Tank - The CNG tank will need to be installed in the trunk of most cars, in the truck bed of most trucks, or behind the back seat of an SUV or van. Sometimes smaller 11" diameter tanks can be installed underneath some vehicles.
Filling Station Availability - Some areas of the United States have few or no filling Stations.

When is the best time to buy?
Buy while gasoline prices are low and our prices are the lowest. When gasoline prices are high our prices may go up and we may run out of stock as demand is very high.

New Price Matching
We will match the price of any USA stocking competitors advertised price on any comparable CNG kits, parts or tanks.

All our conversion kits, tanks, and parts have a 1 year parts warranty. 

Stainless Steel Fittings Option
For a small additional cost we can supply 1/4" or 3/8" stainless steel fittings so you can install stainless steel tubing instead of the steel tubing that comes with our kits.  We do not supply the stainless steel tubing.  We recommend our steel tubing as it is lower in cost and much easier to install.  Call to order if desired.

Why we recommend our mixer kits for do it yourself and for experienced installers.
1.  Our mixer kits are easy to install and adjust.
2.  They are lower in cost.
2.  They use the oxygen sensor to adjust the fuel ratio so the engine runs with the same fuel ratio and exhaust temperatures eliminating any engine or any other damage to your vehicle.
3.  You do not have to wait for the engine to warm before you can run on CNG.  Mixer kits run on CNG immediately.  
4.  They run well in all weather conditions.
5.  Our mixer kits are easy to install and program.

 Warranty Information

1 Year

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 Product Reviews

Write review

  1. Excellent CNG Kit for Carbureted Enging 5 Star Review

    Posted by on 12th Apr 2013

    I installed the CNG Conversion Kit For 8 Cylinder Carburetor Gasoline Engines up to 6.5 Liters Model CNGC8.

    My engine is a Chevy 350 V8 / 5.7L in a 1958 Chevy Pickup truck. My carburetor is a Quadrajet.

    Everything installed perfectly.
    Because the motor is in a truck, there was plenty of room to install regulator,
    associated stepper motor and mixer. I did have to purchase some 4" intake hoses and air filter to get the mixer into the intake system, but that was expected and was spelled out in the instructions and on this website.

    I used the software from this site to check out the system operation and it worked fine.
    I actually used the software to setup the initial value of the stepper motor to a more closed position, to smooth out the switchover from gasoline to CNG.

    I have a wideband AFR gauge/controller from PLX. The PLX unit uses a wideband oxygen sensor but has a simulated narrow band terminal.
    I used the simulated signal from the PLX controller instead of installing the single band oxygen sensor that came with the kit.

    Because this is a closed loop system, the stepper motor adjusts the amount of gas to the mixer based on the oxygen sensor voltage.
    The proof that this works fine is that my AFR gauge shows a fairly steady 14.7 (Lamda = 1), when using CNG. When I use gasoline, my AFR varys constantly.
    Also, hooking up a laptop and using the software tool shows the oxygen sensor toggling above and below the desired .5V(500MV) level and also displays the stepper motor automatically changing position to accomplish the desired LAMDA 1 (.5V).

    I would recommend using an electric fuel pump because to run on CNG requires switching the Change Over Switch(COS) to neutral which stops the gasoline flow by shutting off the supplied gasoline solenoid and then running the motor until the carburetor fuel bowl runs low on gas before switching the COS to the CNG position. This works OK with a mechanical pump, but to switch back to gasoline mode requires refilling the carburetor bowl by cranking over the motor to activate the mechanical pump. This takes a lot of cranking and could drain your battery. Also, for some reason, the gasoline solenoid only has a 1/8" opening, so this also slows down the refill process. I added an electric fuel pump and a fuel pressure gauge so I can tell when the carb bowl is full before I turn over the motor to run on gasoline.

    There were a couple of logistical issues, but all were quickly resolved by the dedicated staff at EWS.
    I would definitely recommend this CNG kit because of the high quality components, good instructions and the excellent support of the EWS people.

  2. Great CNG Conversion Kit 5 Star Review

    Posted by on 4th Feb 2013

    I must admit, I was skeptical when I initially started looking into CNG conversions. Dealing with companies via the internet can be a little hairy, but this company and their products came through with flying colors. I installed a kit on my 2004 Silverado (and subsequently one on my 2003 Galant) and it has exceeded my expectations hands down. The employees have been a pleasure to work with and are very knowledgeable. They have been willing to assist when I need them, call back when they say they will and truly stand behind their products. I had a small issue with one component in the kit and they immediately sent out a replacement – no questions asked – and even threw in a few extra compression ferrules at no cost. It’s hard to find good, reputable companies to work with these days; these guys are it. The product has – and continues to – work as described. It’s been installed a little over a year and has been flawless. If you are at all hesitant to take the CNG plunge, don’t be. This company will take care of you. At the time I am writing this, gasoline is $3.50/gallon. CNG is $1.50. My kit has an estimated ROI of about 1.5 years with the mileage I put on. I am looking forward to a cost effective at-home filling station next.

20.00 LBS
Calculated at checkout
* Fill Nozzle Type:
* Mixer Size Needed:
* Year of Vehicle:

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* Make of Vehicle:

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* Model:

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* Number of Cylinders:

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* Engine Size in Liters:

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