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Fuel Delivery


magifesq

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Best way to convert from homogenous charge to stratospheric charge fuel delivery? Been told by engineers with PHDs that the vacuum on the engine from the butterfly valves on the carbs/TBIs rob power, just wanting to get more efficient. In other words - best way to go from butterfly valves and carbs to fuel pump and progressive fuel delivery no butterflies.

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I'm going to say its not possible. How would you control airflow into the engine?

It's actually very possible, and very common. It's called a Diesel engine.

The more fuel you add the faster the engine spins, it always wants to be stoich, if you take fuel away, it'll slow down (rpms) because the charge is cooler, if you add fuel it'll speed up because the charge is hotter. There are no spark plugs, the fuel is injected directly into the cylinder at the time the spark plug would fire, burning immediately.

This won't work with a gasoline engine. Even direct injection gasoline engines have a throttle valve. If you pull fuel from a gas engine, it gets hot and melts pistons. If you add too much fuel it goes fat and will eventually bog out. Diesel and Gasoline burn very differently, it's diesel's burn properties that make such a thing possible. Actually it was Peanut Oils burn properties that made it possible, but back in the day fuel oil was cheaper so it was substitued. But even todays diesel engines will run on Veggie oil, peanut oil, Kerosine, lots of different stuff. Basicily if it'll burn, you can run it in a diesel. :D I <3 diesel engines their pretty much the most perfect internal combustion engine in existance. Compression Ignition is the most efficient, and cleanest burning way to burn a fuel, squeeze it till makes it's self so hot, it spontaniously combusts.

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It's actually very possible, and very common. It's called a Diesel engine.

The more fuel you add the faster the engine spins, it always wants to be stoich, if you take fuel away, it'll slow down (rpms) because the charge is cooler, if you add fuel it'll speed up because the charge is hotter. There are no spark plugs, the fuel is injected directly into the cylinder at the time the spark plug would fire, burning immediately.

This won't work with a gasoline engine. Even direct injection gasoline engines have a throttle valve. If you pull fuel from a gas engine, it gets hot and melts pistons. If you add too much fuel it goes fat and will eventually bog out. Diesel and Gasoline burn very differently, it's diesel's burn properties that make such a thing possible. Actually it was Peanut Oils burn properties that made it possible, but back in the day fuel oil was cheaper so it was substitued. But even todays diesel engines will run on Veggie oil, peanut oil, Kerosine, lots of different stuff. Basicily if it'll burn, you can run it in a diesel. :D I <3 diesel engines their pretty much the most perfect internal combustion engine in existance. Compression Ignition is the most efficient, and cleanest burning way to burn a fuel, squeeze it till makes it's self so hot, it spontaniously combusts.

ok you got me on the diesels. The original question was about a conversion. To my knowledge GM (in their infinate wisdom) made a 350 diesel and put it in a few G body cars. Sorry some of the diesel kids at school made me bitter about compression ignition. Blowing a huge cloud of smoke is far from efficient and quite frankly pisses me off when i'm behind them on the bike and they want to pipe off.

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A high compression Diesel is anywhere from 22:1-28:1 a low compression/High boost Diesel is normally ~ 18:1

Yes they did, and they did horrible jobs on them, essentially they were SBC 350's with different pistons and heads on them. they were rushed out to be fuel economic solutions and they permanently marred Americas view on Diesels.

As for your friends with the diesel trucks, the black smoke just makes it easy to identify the white trash/hillbillys. all that is is wasted, unused fuel. when you reach that point your actually costing power. A properly setup, and tuned diesel doesn't smoke like that.

Here's a vid, they smoke at the line, but look at them going down the track, there is significantly less smoke, while it's still there, it's not what you see HillBillys spouting out in their POS's.

Here's a good vid of that truck making a full pass. Ever heard of an 8 second diesel :D

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Early motorcycles tried using aircraft fuel systems, long before fuel injection. Aircraft carbs run on gravity feed only, no float bowl, and no butterfly valve. Getting them tuned right is tricky. Good for drag strip.

some famous names were Lake, Posa and Star.

To function with gravity feed fuel only, there has to be some vertical distance between the fuel tank and the injector. Aircraft have about 12 inches of head pressure. Motorcycles have less, usually.

So that means keeping the tank full to help out. And possible having to raise your fuel tank (or lower your carb). I've read and heard of attempts to create a pressure feed system for these, but none ever worked right.

Generally in the range of 15% to 25% horsepower gains.

Frankly, I'd look into bigger bore smooth-bore Mikuni carb kits instead, for a non fuel injected engine.

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Diesel motorcycles seem to be common, but seldom for sale. I've seen a lot of conversions. The Royal Enfield conversion shows up for sale once and a while. I guess there's a good kit for it. On a bike, a diesel is slow to get moving, but ok for cruising. They are not fast, they cruise at a lower speed.

My favorites:

http://www.peace65.freeserve.co.uk/Pictures/royalenfield.htm

440lombardini.jpg

http://www.dieselmotorcycles.com/

M1030M1.jpg

A commercial model will some day be for sale, from HDT Technologies. It is expensive.

MD670F "Bulldog" (US)

l_black_flag.jpg

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Here's a youtube link of some guys using hydrogen gas on a small engine stratified. Engines don't care about the fuel source be it gas, alcohol, propane, butane, etc.

If these guys can do this with a pressurized can of hydrogen, it will be much easier to do with gasoline. http://www.youtube.com/watch?v=RqONufGbKZk watch from about 5:30 - 6:30

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