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Discussion Starter · #1 ·
Bought my Cruze Diesel about 3 months ago, recently drove to ATL from Cincy on one tank of gas (ave 45mpg), I was really impressed, after Atlanta I drove to Tampa where I put on a Propane "adder"... we enriched the air supply with 1.5 cfm of propane variably beginning at idle, mid and cruising parameters. The small amount of LP gas displaced enough fuel to gain 27% giving me just a hair over 57mpg on my return from Tampa back to Cincy.

*I must note that I was setting my cruise control at 75mph each way and other than the up and down freeway of Tenn. both trips were made with no traffic issues or stoppages.

I am using 1 gal of propane every 130 miles so my 8 gal (44lb) tank is lasting a little more than 1k of driving.

Now that i'm back home and driving in a more city environment I'm still 20% better fuel economy than when I was daily driving stock.

Dyno will tell the whole story as far as performance gains are concerned, not scheduled for a couple weeks; There is a noticeable increase in torque; I honestly thought something was wrong with my car and was about to head to the dealership when I realized I was out of propane, filled the tank for $16 and it was back...

Had it not been for the conversion center being really excited about working on a Cruze Diesel and letting me be the guinea pig "on the house" I would have never in a million years thought that the outcomes would have been so good.

I've always loved driving for the sake of driving but now the experience has just been cranked up a notch... I'll never leave home without topping off both tanks.
 

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I will add pics soon, although the unit itself is mostly hidden within two boxes and with the lack of extra space under the hood, the hardest part of the whole process was finding the best place to mount the bracket... I will be getting an new aluminium set of boxes to switch out from the plastic they are using for R&D, but those are just cosmetic details...
 

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This isn't new, been used in the diesel world for a few decades. Glad to see someone testing this out, can only imagine there will be a kit you can buy at some point.

Most of what I have read once you figure in the cost of the kit and propane the mpg increase is a wash. Only real reason to add this is to make more power. If a 6.6duramax can make 50hp safely(or 100hp if you want to risk breaking things), how much power does this increase on a 2.0? my guess not much.

I suspect the change in terrain more the reason how you saw a 27% increase in MPG, even a slight downhill route easily will gain 10 mpg over the other direction. I see this daily in the hills around where I live, even the sections that appear flat do most of the time have an elevation drop in one direction or the other.
 

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It does sound interesting, but I will say that the change in direction can make a huge difference as well. Also, there could be the whole headwind/tailwind thing. I think more testing would definitely be needed.
 
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Propane is super expensive. I am curious about the cost vs gains. If you could almost buy 2 gallons of diesel to 1 gallon of propane...
 

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Propane is super expensive. I am curious about the cost vs gains. If you could almost buy 2 gallons of diesel to 1 gallon of propane...
Exactly, this is not worth the cost at all for the little gains one will make, though I would love to be proven wrong. Since you can do meth injection on a diesel just like some of the gas cruze owners use I would think it would be a cheaper and better alternative for making power.

Looking online at other diesels vehicles with meth kits, looks like Snow performance is who makes them. This is the same company that makes the kit for the 1.4T.
 

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Propane is super expensive. I am curious about the cost vs gains. If you could almost buy 2 gallons of diesel to 1 gallon of propane...
Here it is the opposite propane (LPG) is about half the cost of petrol. I had a Commodore that had duel fuel and could run on gas or petrol with the push of a button. Do you lose space in the trunk like this? Tank here holds 70 liters (just over 18 gallons US).
View attachment 78138
 
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Discussion Starter · #11 ·
Propane is super expensive. I am curious about the cost vs gains. If you could almost buy 2 gallons of diesel to 1 gallon of propane...
not sure where you are buying your propane to make it more expensive than diesel, the absolute highest I've bought it is on the interstate Flying J for 2.79/gal (diesel $4.10). but the local propane dealer is selling by the gallon for 1.89 (3.89 diesel). I'm using 8 gallons of LPG per 1,040 miles at a cost ave of $20 per fillup...
knowing that the efficiency of the CTD is very very good, this system does limit ROI but for overall driveability and added pep it's definitely been worth the kit.
Large trucks and over the road tractors is what these kits are designed for, the less efficient the engine the more savings and power gained, a cost per mile of savings of 5 cents for a trucker driving 50-100k a year is huge and ROI is realized in a very very short amount of driving.
 

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Yep that makes economical sense, now you have to fill propane, Diesel and a DEF tank. I would be more interested in dyno runs with and without the system installed, thats the only thing useful this kit does.

I suspect your cost per mile is not any better than before and is probably worse now. If it cost $20 to fill the propane every 1000 miles, that adds 2 cents a mile to your costs. At that rate a gas cruze probably has a lower cost per mile.
 

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not sure where you are buying your propane to make it more expensive than diesel, the absolute highest I've bought it is on the interstate Flying J for 2.79/gal (diesel $4.10). but the local propane dealer is selling by the gallon for 1.89 (3.89 diesel). I'm using 8 gallons of LPG per 1,040 miles at a cost ave of $20 per fillup...
knowing that the efficiency of the CTD is very very good, this system does limit ROI but for overall driveability and added pep it's definitely been worth the kit.
Large trucks and over the road tractors is what these kits are designed for, the less efficient the engine the more savings and power gained, a cost per mile of savings of 5 cents for a trucker driving 50-100k a year is huge and ROI is realized in a very very short amount of driving.
I pay $3.19 a gallon for my home boiler in NJ. but when I checked the BTU's per gallon of propane vs the BTU's per gallon of diesel I was quite surprised to find out how little energy you get out of propane. There are BTU conversion sites on the web that tell you what you are really getting for your money. I have been getting screwed by propane for years until I put in a pellet stove. Now I am sticking it to the man. Wish I could run a car on wood pellets. However if you are getting good results I wont argue with success.
 

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The power and mpg increase of propane is due mostly to the fact that it increases the percent of diesel fuel that burns. The propane itself is a tiny %, not nearly enough to account for the hp gains.

Sent from AutoGuide.com App
 
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