Fuel Warmer and Fuel magnet?

[TOOSTUBBORN2FAIL]

one thing to point out, there will be a point where heated fuel might work against you

with the new 4 stroke motocross bikes, the ambient heat from the engine can heaet the gas in the plastic and carb that it boils in the carb, and theyve had significant problems with the engines failing to run right after the fuel begins to boil. Bikes have been known to misfire and even flame out on decel. I doubt the fuel temps in the carb are much over 200 degrees F.

*Im just guessing, but id say to a point, warmer fuel might get better mileage, but there would be a point where it would start to work backwards without a significant redsign of the fuel system. Most fuel systems are designed to work with a liquid fuel, and to take advanage of heated fuel, they would need to work well with a fuel in gas form.

[Frank Lee]

[aerohead]

Originally Posted by Christ

So they have throttles, but the claims don't allow for the use of them, if I read that correctly?

So that would mean it's horribly inefficient when used except in a very small range of operation, correct?

I really need to get the book ( you'd get a kick out of some of the drawings ) before I can best represent them (there are 12 0f them ).
Throttles are horrible! They have a Cd 1.11,not a pretty picture for passing fluids,gases,etc..
The Diesel has a low speed advantage over S.I.engines due to it's lack of throttle,which is lost around 80-mph,when S.I.-engined cars are operating closer to WOT,with higher volumetric efficiency of the open hole.
My CRX has a 3-BBL carb and at reasonable highway speed is at WOT for that 2nd "cruise" barrel which probably gives it some advantage over a partially-cracked large throttle-body of a EFI engine operating at high drag angle of attack.

[Christ]

This is why I like gated throttle designs. There is no "angle of attack" scenario, because the flaps open apart in the middle, leaving an unrestricted path for airflow. I believe there is an aftermarket carb company also working on a throttle body which opens radially, like doors in sci-fi movies, to allow for unrestricted airflow, as well.

Of course, out of all of them, I still prefer GDI with no throttle plate.

[cfg83]

Christ -

Oooooooooh, neato :



I guess the only concern would be the KISS factor, or the alien universe hordes.

Who makes gated throttles?

CarloSW2

[Christ]

Carlos -

Precisely, but imagine that it's tapered fore and aft of the opening to allow for a smooth inflow and outflow from the throttle plate. The design is novel, but way too complex, IMO, and we'll probably never see it. I can't even find a patent for it, but I saw drawings for it online somewhere a while back.

The gated carb design, some race carb manufacturer makes it, I'm currently googling my arse off trying to find it.

[dwtaylorpdx]

They are called Slide Valve throttle bodies, been around for quite a while.

Some Methanol sprint cars, F1 cars and some Euro dirt cars run them.

Lucas made one of them.

They are very very effective in situations where you want throttle response.

Dave

[Christ]

Originally Posted by dwtaylorpdx

They are called Slide Valve throttle bodies, been around for quite a while.

Some Methanol sprint cars, F1 cars and some Euro dirt cars run them.

Lucas made one of them.

They are very very effective in situations where you want throttle response.

Dave

No, they aren't [that type of carb]. Still can't find an example of it, though, and I don't even have the DVD of the last show I saw them on... (part of power block from back in the day).

The throttle valve is still actuated the same way, with a cam, except it's a half-circle port with a half circle throttle blade that tucks into the port at WOT. Air doesn't split to go around it, because there is only one opening in the throttle port. It has a much lower Cd than traditional throttle assemblies because of this, but a larger throttle cam is required for more precise throttle response, because if the same size cam is used, you're only able to get half the airflow that you'd be getting at a given RPM/throttle setting with a normal carb.

The other design that I thought was better even than that one, is a square throttle bore with two gates that open apart from each other in the center. It uses a single throttle cam and a pair of cogs. The throttle cam controls one plate, the cog opens the other plate to the same angle at the same time, but they both open the same port, and close together when the throttle is closed.

[rmay635703]

I believe there is merit to fuel heaters especially in the cold tundra up here. Only about 30% of a tank of gasoline is actually gasoline, the rest is additives and heavier compounds (boy the crap gas we have) As such although most of the fuel burns to some extent only maybe half burns completely and clean the rest has to finish burning once it exits in the cat. If you have ever taken a CAT off a car you will know it, smells like raw gas out the tailpipe.

Originally Posted by SVOboy

Before you go throwing money at magnets, I would suggest giving this a read: Fuel saving gadgets - a professional engineer's view

Or go to harbor freight and buy one when they are on clearance for $2-$5. If you get tired of the thing it works well as fridge magnet and has a cool looking lable on it. Speaking of which you could just put a cow magnet, fridge magnet or whatever on there if it makes you happy.

There have been a couple sucessfull (as tested by the EPA) fuel magnet/dissimilar metal jobbers like the vitalizer. (Before flaming read the papers on the thing, it did very slightly improve FE but not enough to cover its cost)

The fuel economy improvement was a whopping 1% meaning you better not spend very much on a magnet.

[cfg83]

rmay635703 -

Originally Posted by rmay635703

...

There have been a couple sucessfull (as tested by the EPA) fuel magnet/dissimilar metal jobbers like the vitalizer. (Before flaming read the papers on the thing, it did very slightly improve FE but not enough to cover its cost)

The fuel economy improvement was a whopping 1% meaning you better not spend very much on a magnet.

I wish I had the reference, but I remember reading that in lab settings it works, but only *if* you have a huge magnet, maybe MRI style. I think that's the "kernel of truth" to the fuel magnet thing.

CarloSW2