RossD
RossD PowerDork
11/6/14 7:28 a.m.

I was behind a AT&T van and it had a round CNG sticker on the back door... This piqued my interest a bit and I pondered the "Grassroots Effect". But as it turns out, I don't know what that could be...

ie: What is the performance potential of a LSx style engine running on compressed natural gas?

Leafy
Leafy Reader
11/6/14 7:49 a.m.

If you lived in socal you could piss off the dirty hippies driving the CNG powered honda civics by hogging their pumps to fillup, but thats about all I can see from it. And also finding on of those trucks in the junk yard would give you a super cheap set of MONSTER HUGE fuel injectors.

Apexcarver
Apexcarver PowerDork
11/6/14 8:05 a.m.

http://gmauthority.com/blog/gm/gm-engines/lc8/

looks like they take a bit of a power hit in OEM configuration.

I have heard of propane race carbs though...

Could be interesting

At least according to Roush "Propane autogas provides similar range, horsepower, torque, and towing capacity to gasoline-powered vehicles. It contains a higher octane rating (105 octane) than gasoline, which helps guarantee a similar performance feel." http://www.roushcleantech.com/faq/propane-autogas

edizzle89
edizzle89 Reader
11/6/14 8:35 a.m.

if its anything like diesels running natural gas then it will be a giant pile of oil leaking crap, based on personal experiences

Thinkkker
Thinkkker UltraDork
11/6/14 9:22 a.m.

I have not seen a vehicle which gains power on CNG. The actual MPG is slightly lower too. Now, if you can fill at home and such, it may make sense, but if the conversion is not already done, it can be an expensive option. You can piece it together yourself, but I have not done a lot of research on this. I think you may still be at 2k+ for new parts.

Fueled by Caffeine
Fueled by Caffeine MegaDork
11/6/14 9:39 a.m.

CNG and Propane run upside down and at all angles... Good for Off-road.

Leafy
Leafy Reader
11/6/14 9:42 a.m.
Fueled by Caffeine wrote: CNG and Propane run upside down and at all angles... Good for Off-road.

Only if 2 stroke. The fuel type still doesnt stop all the oil from draining past the piston rings when you tip the thing upside down.

RossD
RossD PowerDork
11/6/14 9:50 a.m.

How about with some boost!?

thewheelman
thewheelman New Reader
11/6/14 10:15 a.m.

I used to work for one of the largest CNG upfitters in the industry - Westport.

CNG has an equivalent octane rating of 130 (boost friendly!), the issue is fuel storage. Since it is a compressed gas, you need more storage volume than gasoline per Gasoline Gallon Equivalent (GGE).

We converted Ford vans and pickups for AT&T (among others), and on the vans we had to remove the gasoline tank and spare tire crossmember to store 20 GGE of CNG on the vehicle. In some cases we would add an additional cylinder inside the vehicle to add another 5 GGE of storage. Heavier duty vehicles (Ford F450/550/650, etc.) can handle more tanks due to available space and weigh capacity.

Conversion prices are starting to come down, but for a CARB/EPA certified, FMVSS crash tested conversion, you're still going to pay $10,000 to $20,000, depending on how much fuel storage you want/can fit in/on the vehicle. There are cheaper conversions, but they're using Chinese tanks, and most likely aren't crash tested, or emissions legal (even if they tell you they are).

If you shop around, you could put together a Grassroots system for a few grand...

Lots of fly by night companies are popping up, promising great things. In this industry, like many others though, you do get what you pay for.

Fueled by Caffeine
Fueled by Caffeine MegaDork
11/6/14 10:28 a.m.
Leafy wrote:
Fueled by Caffeine wrote: CNG and Propane run upside down and at all angles... Good for Off-road.

Only if 2 stroke. The fuel type still doesnt stop all the oil from draining past the piston rings when you tip the thing upside down.

ohh, right. You must have tons of off road time with your cheese slicer wing Miata. Got it. -1.

tuna55
tuna55 UltimaDork
11/6/14 10:43 a.m.
Fueled by Caffeine wrote:
Leafy wrote:
Fueled by Caffeine wrote: CNG and Propane run upside down and at all angles... Good for Off-road.

Only if 2 stroke. The fuel type still doesnt stop all the oil from draining past the piston rings when you tip the thing upside down.

ohh, right. You must have tons of off road time with your cheese slicer wing Miata. Got it. -1.

Dude, harsh much?

Fueled by Caffeine
Fueled by Caffeine MegaDork
11/6/14 10:45 a.m.
tuna55 wrote:
Fueled by Caffeine wrote:
Leafy wrote:
Fueled by Caffeine wrote: CNG and Propane run upside down and at all angles... Good for Off-road.

Only if 2 stroke. The fuel type still doesnt stop all the oil from draining past the piston rings when you tip the thing upside down.

ohh, right. You must have tons of off road time with your cheese slicer wing Miata. Got it. -1.

Dude, harsh much?

He failed to follow protocol and put in the preq smiley if he was joking. follow protocol or get burned. Additionally, he displayed that he knows no knowledge of the subject as Propane swaps are very popular in the off road world for all angle running. He just wanted to be a jerk..

so..

m3h.

Leafy
Leafy Reader
11/6/14 10:49 a.m.
Fueled by Caffeine wrote:
tuna55 wrote:
Fueled by Caffeine wrote:
Leafy wrote:
Fueled by Caffeine wrote: CNG and Propane run upside down and at all angles... Good for Off-road.

Only if 2 stroke. The fuel type still doesnt stop all the oil from draining past the piston rings when you tip the thing upside down.

ohh, right. You must have tons of off road time with your cheese slicer wing Miata. Got it. -1.

Dude, harsh much?

He failed to follow protocol and put in the preq smiley if he was joking. follow protocol or get burned.

Which smelly?

tuna55
tuna55 UltimaDork
11/6/14 11:01 a.m.
Fueled by Caffeine wrote: He just wanted to be a jerk..

Know anyone like that?

Takes one to know one?

Pot/Kettle...?

Fueled by Caffeine
Fueled by Caffeine MegaDork
11/6/14 11:20 a.m.
tuna55 wrote:
Fueled by Caffeine wrote: He just wanted to be a jerk..
Know anyone like that? Takes one to know one? Pot/Kettle...?

Understood.

Petrolburner
Petrolburner Reader
11/6/14 11:27 a.m.

I looked into running propane on my 22R 4Runner. Would be good for the all angle stuff, but there are so few instances when I would be in position where EFI would not get the job done, but propane would, that it wasn't worth all the downsides.

ebonyandivory
ebonyandivory SuperDork
11/6/14 11:33 a.m.

The propane-powered 4x4's are just spraying for mosquitoes while they winch their rigs back on all fours.

Fueled by Caffeine
Fueled by Caffeine MegaDork
11/6/14 11:46 a.m.
Petrolburner wrote: I looked into running propane on my 22R 4Runner. Would be good for the all angle stuff, but there are so few instances when I would be in position where EFI would not get the job done, but propane would, that it wasn't worth all the downsides.

Propane only makes sense for currently carb'd engines. It's an easier/cheaper swap than EFI in some cases.

Knurled
Knurled PowerDork
11/6/14 12:31 p.m.
RossD wrote: I was behind a AT&T van and it had a round CNG sticker on the back door... This piqued my interest a bit and I pondered the "Grassroots Effect". But as it turns out, I don't know what that could be... ie: What is the performance potential of a LSx style engine running on compressed natural gas?

We converted our shop truck to dual-fuel CNG, as preparation for doing this as a service for utilities.

Downside: It's expensive to start out. Figure $10-12k when all is said and done. The tank is really expensive, but not too bad when you consider that is is a huge DOT rated 3600psi cylinder. Feels like slightly less power by the butt dyno, maybe 5%.

Upside: Refuel in the building/at home (the fueling station is another big chunk of that 5-figure bill) or $.80-1.20 per gallon equivalent at stations with CNG pumps. Oil change interval can be extended 2-5x, other maintenance items last a lot longer too. Very clean burning fuel.

Most utilities who get CNG conversions say that it pays for itself within a year or two.

Kenny_McCormic
Kenny_McCormic PowerDork
11/6/14 4:00 p.m.
Leafy wrote: And also finding on of those trucks in the junk yard would give you a super cheap set of MONSTER HUGE fuel injectors.

They truly are monster huge, like too big for most liquid fuel applications, at least 160lb/hr. Might work for a alcohol race motor that doesn't do much idling. Probably good for a TBI application.

Leafy
Leafy HalfDork
11/6/14 4:11 p.m.
Kenny_McCormic wrote:
Leafy wrote: And also finding on of those trucks in the junk yard would give you a super cheap set of MONSTER HUGE fuel injectors.

They truly are monster huge, like too big for most liquid fuel applications, at least 160lb/hr. Might work for a alcohol race motor that doesn't do much idling. Probably good for a TBI application.

Or building 2 turbo 4 cylinders that want to make 600hp+ on e85. The 2000cc/min EV14 injectors you buy from ID or FIC are LNG/LPG injectors.

thewheelman
thewheelman New Reader
11/6/14 4:16 p.m.

Some of our old conversions used the then industry standard Bosch 842 160lb/hr injector, and they were also popular with the big horsepower gasoline engine builders. Like no idle, WOT all the time engine builders.

So popular that one of our warehouse guys created a nice Craigslist/Ebay enterprise by stealing our inventory and selling it. He's in a little bit of legal trouble now...

Fueled by Caffeine
Fueled by Caffeine MegaDork
11/6/14 4:19 p.m.

I've looked into the CNG conversions and vehicles for some time. A home refueling setup and a CNG civic or F150 would be a great around town vehicle. Fuel cost is about $0.50-$1.50 per gallon equivalent depending on what your local gas rates are, you need to pay for the price of the recharging station and you do need to submit taxes to the government for the CNG use as a road fuel, but if you drive a lot around town.. It seems like a great cheap way to get around.

http://www.ebay.com/itm/Chevrolet-Silverado-2500-2500-HD-2004-chevy-silverado-2500-hd-ext-cab-rwd-cng-ngv-natural-gas-/191400549158?forcerrptr=true&hash=item2c905c9b26&item=191400549158&pt=US_Cars_Trucks

http://www.ebay.com/itm/Ram-2500-Tradesman-Crew-Cab-Pickup-4-Door-2013-ram-2500-tradesman-crew-cab-pickup-4-door-5-7-l-/251706394434?forcerrptr=true&hash=item3a9adec742&item=251706394434&pt=US_Cars_Trucks

http://www.ebay.com/itm/Ford-Crown-Victoria-Base-Sedan-4-Door-1996-ford-crown-victoria-base-sedan-4-door-4-6-l-/151463892251?forcerrptr=true&hash=item2343f3951b&item=151463892251&pt=US_Cars_Trucks

http://www.ebay.com/itm/Honda-Civic-GX-Sedan-4-Door-2012-honda-civic-natural-gas-/231382006981?forcerrptr=true&hash=item35df713cc5&item=231382006981&pt=US_Cars_Trucks

Bi-fuel: http://www.ebay.com/itm/Ford-Expedition-LIMITED-Bi-Fuel-Propane-LP-and-Gas-Ford-Expedition-limited-4x4-fully-loaded-rear-/281483695230?forcerrptr=true&hash=item4189bc547e&item=281483695230&pt=US_Cars_Trucks

http://www.reuters.com/article/2013/10/04/us-naturalgas-home-refueling-insight-idUSBRE9930D120131004

Eaton is rumored to have a $500 fueling station coming out. Could be 200 Gallons to make up the cost...

NGTD
NGTD SuperDork
11/6/14 6:05 p.m.

As noted by an earlier poster, the equivalent Octane rating of CNG is approx. 130-140. CNG will love boost or seriously leaned compression ratios.

There was a guy a few years ago that was running a drag car using near-diesel like compression (16:1 or something like that).

The downside is range - the energy density of CNG is much lower than gasoline. So most run duel-fuel application that do not take advantage of CNG other than its cheap. So mostly it is used by utilities and fleet applications.

A turbo car could potentially use 2 different maps one for gas and one for CNG. Then on CNG you could crank the boost!!!

oldopelguy
oldopelguy SuperDork
11/6/14 7:20 p.m.

Around here the parts are easy and cheap, if you buy a used Schwanns truck. I see them for sale all the time for under $2k for a used Topkick.

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