I realize that all the different configurations will have different results so I'm just hoping to get a general idea of how much propane I can expect to use. My current setup on a 72 blazer is mild SBC 350 with 4x4 cam, Holley off-road avenger, headers, 37" tires, 4.56 gears. I'm curious approximately how much a full size might use on a trail in about a days time. I'm wanting to do the conversion but I'm limited to space for tanks. Thanks for any help. Sean
CK5
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Propane consumption?
- Thread starter mason72
- Start date
I've been running propane on my Blazer for the last 8 years or so, combination of a 383 small block and LS/6.0L.
On the trail (we mostly have rocks so mostly around idle), it uses very little, way less than gasoline. Probably talking 3-4 gallons in an 8 hour day.
Any kind of spirited driving though and it goes through fuel fast.
On the trail (we mostly have rocks so mostly around idle), it uses very little, way less than gasoline. Probably talking 3-4 gallons in an 8 hour day.
Any kind of spirited driving though and it goes through fuel fast.
I run propane in my scout with Chevy drivetrain, stock 350 th400/203, 1-tons with 4.56s and 35s and have similar experience.
One 8 gal tank will last me all day on the trail and then some. On the pavement I get about 10 mpg running about 50mph or so. I have mounts for two tanks and always make sure I have a full on before I hit the trail.
One 8 gal tank will last me all day on the trail and then some. On the pavement I get about 10 mpg running about 50mph or so. I have mounts for two tanks and always make sure I have a full on before I hit the trail.
beags86
Eastbound and Down
Man that would be great but my healthy big block with a full days crawling uses 3/4 to a full 8 gallon tank. I do have a standard trans and and older style motor. I do use the hand throttle alot as a third foot. I bet if I had 37s it wouldn't be as bad.
Pretty much sums it up. I run 1 ten gallon tank and 1 eight gallon tank and they last me the weekend...This is all offroad with a stock 350, deep gearing and 44" tars...So I tend to idle over a lot of the smaller stuff.
I'll know better when I get mine running and use it. I've got mounts for 2 tanks. I only have 8 gallon tanks now. I'm looking for 10 gallon to get just a little more. (They're hard to find used) I figure I can always have a couple of spare tanks in the tow rig. Sounds like 2 would last a normal day on the trail. I've got a dual mixer set up on a 400-500hp 377 SB. So I'm interested to see how thirsty it will be when it's done?
Thanks for all the replies. Anyone have any pics of how and where they mounted the tanks? I am going to end up with a bobbed and narrowed back end with a cage and a tool box behind rear seat when I'm done so I'm having a difficult time trying to decide where to fit 2 tanks. Thanks Sean.
Tools behind the passenger seat and crate with misc stuff behind driver. Spare driveshaft fits back there too. I now also have a toolbox drawer behind the tanks now that the tailgate got KIA.
That's how I've got mine mounted. Probably doesn't help if you want to put a toolbox in the rear? I kept them tight together and tight to the seat. I eventually would like to narrow the back end too.
My pics may not help much since it's in a scout (much less room than a blazer mind you) but I'll post them for the idea.
Cut a hole in the rear floor and welded tube in between two cross members and cut up some of the strap mounts to use the straps and buckles.
Got the overall height of the tanks like 12" lower. I can put a back seat in and store stuff on top of and beside the tanks without having to stack it to the top.
Future plans include dual tank connectors with a solenoid valve so I can flip a switch to switch tanks and then I'll build a hinged cover and a tool box to sit on top.
Cut a hole in the rear floor and welded tube in between two cross members and cut up some of the strap mounts to use the straps and buckles.
Got the overall height of the tanks like 12" lower. I can put a back seat in and store stuff on top of and beside the tanks without having to stack it to the top.
Future plans include dual tank connectors with a solenoid valve so I can flip a switch to switch tanks and then I'll build a hinged cover and a tool box to sit on top.
I was surprised to learn you cant take any propane tanks or vehicles powered by propane thru any of the tunnels in Boston--friend of mine got a hefty fine for having a 20 lb. tank on the back of his camper (factory mount too)--evidently new restrictions due to terrorism from the Dept. Of Homeland Security and Transportation only exempt certain "commercial" vehicles from this policy..
Just something to know in case you had to tow your trucks to an area and go thru any tunnels..other states may not be as worried as MA is,but--..
Just something to know in case you had to tow your trucks to an area and go thru any tunnels..other states may not be as worried as MA is,but--..
My 83 with one tons 456 gears and 39s i drove daily, also has a sm465 and a 450hp 358. I have 2 ten gallon forklift aluminum tanks in the bed, when i figured out miles per gallon it came right to 8-9, now this truck has dual x450 carbs and dual model e impco's. The same motor i ran 108 race gas in and it was about 7-8 mpg. For what you have i would be safe to say you should see atleast 10 or better. The short 34lb tanks are 8 gallon, the long 43lb tanks are 10 gallon.
What works really well is run one line from the engine compartment to the bed, put a t in the line then run a fitting to each tank. Add an in line low fuel light, i turn one tank on and when the light comes on stop and switch to the other. From what i seen when the lights on you have about a gallon or so.
What works really well is run one line from the engine compartment to the bed, put a t in the line then run a fitting to each tank. Add an in line low fuel light, i turn one tank on and when the light comes on stop and switch to the other. From what i seen when the lights on you have about a gallon or so.
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Rob h what is the compression ratio in your 358?
My 358 is 12.5:1, its a 74 350 bored .040 with .220 domed pistons. Its pretty healthy, i tried running one x450 carb but it limited my rpm to 5k and only short bursts. So now i have 2 carbs on an impco adapter. The adapter used one base plate, came out really nice but is a little harder to start.
That's the same set up I'm putting on mine. I didn't think one would be enough. I believe I'm just shy of 12:1. It's been so long since I had that motor built I can't remember. I used to run 110 blended with 93 octane to keep the cost down. With the price of race gas what it is now I thought LP would be the way to go. Back when I use to mud race the race gas was just under $4.00 a gallon.
I'm running a stock vortec 454, single impco model 425 (460cfm) uses about 2 gallons per hour on the trail. Throttle pedal to the floor last about 7 seconds before it shuts off.
Propane motors like compression. My vortec 350 is just under 12-1. I just run a single big forklift tank and its mounted on a slight angle to help keep the liquid down around the J tube when the tank gets low. Theres a bunch of pics on my build thread. 1977k5's tanks are mounted on a similler angle. Do your mock up mounting with a full tank at full ride height with tires on..not an empty tank at full bump on jack stands like I did. ..the first time I loaded a full tank into the mount, I thought I was gonna die. I have a T fitting in my fuel line with and adapter that lets me run a BBQ tank of any size as a reserve or emergency tank. Helps out if someone needs to make a "gas" run for you too.
All the info and pics are great thanks.
