Anybody though of this? Compressed natural gas has a octane rating of 130. Im not quite sure what would be required to convert it over other then some bigass storage tanks and fancy injectors.... But, with a octane rating of 130 and a hell of a lot cheaper then gasoline....... Wouldnt it be possible to make a lot of horsepower on it and run a lot cheaper then gasoline? With 130 octane, it should be boost friendly.. right?

 

one problem would be with it being gaseous fueling, the fuel takes up much more cylinder volume, displacing oxygen and decreasing power output. Forced induction would be required just to get back to NA power levels.

 

That would be a given, but, seeing as the fuel itself has a 120-130 octane rating, and doing a bit of research reveals that it runs a average of 13.1-16.1 compression, It shouldnt be a issue running high boost levels to compensate for it, right?

And also, the a/f ratio for cng is 17.4/1 as opposed to 14.7, being how the gas is already a "gas", the absense of liquid in the fuel should also help prevent detonation on top of the 130 octane rating. Or, am i just retarted?

 

I would think it would be "boost friendly" considering the octane rating...probably the same reason some diesel guys run propane injection? fuel delivery is a little more complicated than liquid since the flow rate of the injectors changes considerably based on the gas density which fluctuates with temp/pressure (obviously) so the computer has to be able to consider these variables alos. the range of the vehicle is greatly decreased as well compared to gasoline due to the lower density gas storage...not to mention the tanks are alot heavier. just throwing out pros and cons for thought

 

I have been doing research on this subject. I think it's a great idea to use CNG as an alternative fuel source. I am planning to build an NA engine specifically designed to run on CNG or hydrogen. I am going to start simple with a carbed SBC due to cost and the ease of tuning.

 

Our company, and my DD vehicle run Natural gas. Good stuff, yes there is a slight difference in power between gas and CNG, according to the company we use to do our conversions, on vehicles we buy that are not converted, or factory by-fuel, they have some blown applications making MONSTER power! There are issues with heads and valves using CNG though. Unless the vehicle has hardened valves or something of the like, they tend to crack over time.

Just last month weve had to replace heads on 3 of our work trucks. Also, the amount of room it takes to mount a tank is rediculous, If any of you drive a cavalier, look in your trunk.

I have approx. 10" depth in my trunk of usable space since the tank takes up the entire thing, and its only 5GGEs, (gasoline gallon equiv.) i get about 4 less miles per gallon on CNG as well. Id be happy to take some pics of different size tanks and post there GGE if people are interested. and even show some of the plumbing under the hood, Just let me know.

But like stated above, the octane rating is huge, and according to shop, their blown applications make monster power.

 

In my opinion, You would be better off having staged injectors with a resevoir of 116 octane. By the time you finish everything, youd be better off with the dual fuel. You would also not be limited to CNG stations.

 

I was thinking more along the lines of filling my gas tank offa the 300gallon thing in the backyard, and cng in oklahoma is half of the price per gallon as gasoline right now. I was hoping with the 120-130 octane, i would be able to run a hellofalot of boost, and still make a lot of power on it.

 

They have, and we have installed, "slow filling stations" at homes for people. Hook it up at night and in the morning its good to go.

CNG stations are scare, but ARE becoming more popular, our pump is at 1.85 per GGE at the moment, we have our own pumping station here, open to the public of course.

You have to remember the pressure a CNG car runs at. I believe their are only 2 options, 3600psi and either 3800 or 4000psi. SO you likley just cant fill off your tank out back. Also, you have to know that CNG is very very finicky when it comes to Combustion. It has to be within a very tight tolerance for AFR. Gasoline can combust in a wide range. CNG is very limited. I dont remember the specifics, but i could get this information with a simple phone call.

Yes, its a great fuel, but its expensive to maintain, IMO, but of course our vehicles run almost 100k a YEAR.

another benefeit, CNG is SO CLEAN! we tested the bosses truck with oil change intervals and he ended up going 8000miles and when the oil was changed it was barley darker in color then the day we put it in. Its a freaking clean fuel.

 

What is so expensive to maintain about it?!?

 

It gets **** gas milage. Our patrol cars were cng and sucked.

 

Even so, its less then half the price as gasoline. And, it burns at a 17-1 ratio a/f.

 

ALL our vehicles run on it, and get on average about 4-7 less miles per gallon. If the company that does the conversion takes their time, and does it right, its not that bad. Also, if its a factory conversion, like my cavalier is, its even better.

We have a brand new fusion that we just did the conversion on that gets on average 3 miles less per gallon.

And to answer the question about maintaing the systems, they arent terrible until something breaks, nothing on them are cheap, the fill valves, the and there are a couple of valves that im not sure about under the hood that get VERY pricey, IIRC, last year on of our ford models that was converted, we ended spending 3 grand on a valve issue.

Things happen, especially when your dealing with pressures in the 3600psi range, also, i miss spoke earlier, the psi ratings are 3000psi and 3600 psi. Although 3000 psi havent been made since the mid to late 90s as i was told today.

you cannot fill a 3000psi system at a 3600 station but can fill a 3600 at a 3000 station.

and to give you an idea, the vehicles we run range from caveliers, to 1/2, 3/4, 1ton and 2 ton trucks, also both of our box vans run on them.

 

Heres a quick look at just one our trucks, to give you guys and idea about tank size and injectors ideas.

The injectors are simply drilled into the composite manifold like a DP Nitrous system. I dont care for this conversion, but it was one our first.

The tank that is pictured is an 8gge tank.









We also have our own fueling station. When you spend the time and effort into the infrastructure as we have, you can learn the tricks and learn how to get some of the best performance out of these things, aside from the overall size and weight of these tanks, i dont mind the CNG at all.

 

Looking at that tank, it would take the entire bed of my truck just to match up to the 32gal tank... Did not realize the gas tanks were that damn big.

 

It's a vortec ls motor in that pic
What kind of mpg and Hp it make with the cng? All I see is that distribution block manifold thing but not where the plumbing leads to the intake

 

Its a company truck it doesnt see a dyno. i can get the mileage from the boss on monday. And yes, their is a difference in power in the conversion vehicles.


I tried to get a good pic of the install in the manifold, but couldnt get close enough, its seriously plumbed just like a direct port nitrous setup. And yes, its a 6.0 lq4 2005 2500hd

 

A patrol car would need a gigantic tank to have any sort of range. Even if the MPG is only slightly lower, I could see why it would suck to have in a patrol car. You would be stopping to fill up several times a day.

 

There is some good info here and some bad as well. The gas mileage should not be any more noticeable that 1-2 mpg on CNG vs Gasoline. If its set up right and tuned properly this is not a concern.

We have introduced well over 750 CNG Trucks/ Tahoes and Vans into the OK market in the past year and have none of these issues being mentioned. Yes storage of it is a big concern and it takes a lot of room for the fuel. We run 21 gallon tanks in our trucks which in reality take about 18-19 gallons of useable space due to expansion upon filling and never really being able to completely empty the tank. There is also a bit of a weight concern due to the tanks..they are VERY heavy...but I think the end result is a great one and a clean one and AMERICAN 100%!!! Looks like the tank in the pictures is a steel tank that is wrapped, we use the Lincoln Composites tank that is Plastic lined with Carbon fiber/mesh fiber wrapping that is damn near bullet proof and WAAAAAAY safer than a $20 gasoline tank that GM gives us. It also weighs a lot less than the steel tanks.

Over the road vehicles need to run LNG for the storage capability that it offers over CNG.

The comment about CNG being expensive to maintain I feel is not true personally. It is $1.39/gallon to fill up your vehicle. The fuel savings alone more than covers the every 10k mile filter change ($100) and 30k mile Tank inspection ($300). The engines have no issues with mileage (that we have experienced) and no issues on the valves. Most of ours are Bi-Fuel which allows you to still start on Gasoline and also lubes the system then after a few miles the CNG switches on and you are good to go. So even if you run out of CNG your Gasoline is still on tap. This is a HUGE mileage boost if you are traveling and will let you go much further between fillups if both tanks are emptied.

The stations are coming on line more and more each month. We helped open up 10 new stations in the past 6 months in Oklahoma and are anticipating 10+ more in OK. Also moving to TX and Louisiana in the next 12 months.

Guys.....CNG IS COMING!! its just slow to catch on due to mis-information, un-informed public and lack of infrastructure. But it is making a very strong stand right now and getting great recognition. There are plenty of benefits of it and tax credits as well depending on state. This is an ALL AMERICAN NATURAL FUEL SOURCE that we have a GIGANTIC ABUNDANCE OF IN AMERICA NOW!!!! Read up on it guys,,,, support it and most importantly USE IT!! It will be a huge help in our fight to become less dependent on foreign oil and also it is CHEAPER!!!!

There is a project in the works right now that I cant talk about until next month that involves a 5th gen....When I can, I will post pics and info on it. I think you will be impressed.

Take care.
Dave

 

Oh...and this is another one of our "Company Vehicles "

Runs 100% on CNG