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RV275 Injectors

Blueox01
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JOHNFAK

JOHNFAK

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I've yet to see > 18mpg, ever, in my vp44 truck. My average DD mileage in the 24v is ~14-16mpg, all city. My 24v gets ~17-18mph @ 65mph, empty, no trailer. 24v = stock everything except bhaf, 5600, no muffler/resonator, 4" turndown behind cab.

Funny - those figures are almost exactly the same as mine before I added my juice. Now ...... +1mpg towing (11-13mpg) ........ +1mpg city (15mpg-17mpg) ....... +3mpg highway (20-21mpg). When I add my RV275's back in {probbaly live with the stalling for now} ....... I expect around +1mpg extra to each of those figures.:woot:

That whole 2000+ RPM thing being instant drop is a bunch of crap. I know everyone preaches it on every forum but I have never seen an instant drop. I do 70 at 2100rpm and get 21mpg doing it. I got 17mpg pulling the trailer at 70 also. Speed kills MPG, not RPM.

Yeah kinda agree on this one. Interesting about the winddrag factor above 55mph (is that figure right mike ?) and the vp44 retartment with rpm. But I hit 20mpg on 65mph cruise control every time. I don't think I am going to see 24mpg running her at 55 mph ..... :shrug:
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ISX

ISX

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The chart is like a mountain pertaining to speed and mpg.

Too slow and you aren't getting anywhere and just running the engine uses more fuel than the distance you travel. Like at 1 mph, your not going to be getting any kind of mileage. You will have to burn an hours worth of fuel basically idling and will have only gone 1 mile.

Too fast and you are going over a lot of distance but it just ends up taking so much power to go that fast that it ends up using a ton of fuel. It would be like driving a billboard through the wind, sure you can go 100mph and get very far in very short of time, but it takes a lot of fuel to push a billboard at 100mph..

Those 2 examples are very drastic but they get the point across.

Now the factors that also come into play that you have to set up for mileage are:

[*]Axle Ratio

[*]O/D Ratio

[*]Tire Size

[*]Vehicle Weight

[*]Aerodynamics

All of those factors are different on every vehicle. They can be pretty close but I doubt everyone has the same tire and the same wear on all of them. Engine have different wear patterns that can affect their efficiency at different RPM's. Like if one engine has more advanced timing than the next, then the more advanced engine will be more efficient higher up in the RPM.

It is a fine art to hone each factor in for perfection and it takes a lot of skill. The biggest problem is getting everything perfected for the variety of speeds we face. Trains have figured this out with the generator/diesel set up. Electric motors do not have "rated RPM's", if they say 50HP they can produce it at any RPM given enough power. The diesels can run constantly at their most efficient RPM with nothing but the fuel rate changing to keep it at that RPM. Everything efficient is at a set speed. Now you see why it is so hard to get our trucks to be efficient. We aren't on rails, we are on roads full of changing speeds. It is possible to keep this efficiency constant with all of the variable drive transmissions (like in the nissan altimas, I think) but obviously they are only on low power engines thus far.

Another issue is load. There is a reason trains don't go 1000 miles with just the engine car by itself, but that is exactly what we are doing when we are not pulling a trailer. We have a huge engine pulling a tiny load and the engine itself is using more power just to turn itself that doesn't need to be used. At 70mph we could get by just fine with a stock 4BT.

Now there is our need for speed or acceleration. Need I say how trains accelerate.. They don't have 100000000000000HP engines to get the 1000 cars to 70mph in 6 seconds. It might be needed for that 6 seconds, but after that you have a huge engine that is nothing but dead weight.

When you pull a trailer, your efficiency goes way up. Look at per pound pulled per drop of fuel and it will be more efficient. You have to get the engine to work hard and that is when it is very efficient. If you have unused HP then you need a smaller engine.

It's interesting how most new semi trucks WITH 80k lbs can get the same mileage as an older pickup truck that is unloaded. Have you seen how they accelerate? That's what I thought. If 14L can pull 80k efficiently, then that means there is 5714 lbs per liter. If you think that is BS then put a 4BT in your truck, leave it stock, leave your truck unloaded, put an 18 speed in your truck (designed for the power, so it would be a lot smaller than the semi trans) and now see what you get for mileage. It might be slow but I have my doubts, I think it would accelerate faster than a semi. To get down to semi speeds, I would throw a 2.5 or 3 liter into my truck and then it would be slow but efficient. I know some people think this is also BS, but you won't be trying to accelerate to 60 in 6 seconds, you will slowly get up there, on hills you will downshift and let the truck slow up the hill and speed down the other side without trying to hold 80mph the entire time.

If you can get out of that "I gotta get to 60mph quickly!" mindset, your mileage will skyrocket. I take a mile to get to 65 when I hit the highway to go to town..

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Rogan

Rogan

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What else is required in running them? Smarty, etc? As mine is stock currently.

rv275 will get you more power if you have an HO 6spd because the flow of their injectors are LESS than a SO. I have 2 sets of rv275 in stock.

Sent from my HERO200 using Tapatalk
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Heavyd1980

Heavyd1980

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ok so what i have seen out of my truck is about 13-14 mpg's with 315 tires, nv4500, edge juice, with 4.10's, now most of that is highway/city driving since i only live about 8 miles from work and its about 50 percent city but that is empty and it doesnt really change unless i am pouring the coals to it!!!:thumbup2:

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Blueox01

Blueox01

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No I hav'nt bought them yet,been too busy trying to earn the funds(donations accepted) just kidding, think i'm going to have Diesel Specialties get them in for me tuesday and get them in.Last run i did stopped for coffee and noticed my truck idling rough,can't think of what happened other than a dirty injector.Runs smooth down the road,just does'nt seem like it hitting all 6 at idle. Injectors have 778k probly time for new.

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Blueox01

Blueox01

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have you gotten your injectors yet?:thumbup2:

No I hav'nt yet, going to have Diesel Specialties here in Omaha get them in for me tuesday,been too busy trying to earn the funds(donations accepted) just kidding.Last run I did I stopped for coffee and noticed my truck idling rough,runs smooth down the road,can't think of what happened other than a dirty injector.Don't know just does'nt seem to be hitting all 6 at idle,injectors have 778k so it's time.
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