I'm thinking with a fuel injected car we could heat the fuel filter, or the fuel rail itself. My biggest concern would be the fuel being so hot it melts the plastic and rubber parts of the fuel injectors.
I'm thinking with a fuel injected car we could heat the fuel filter, or the fuel rail itself. My biggest concern would be the fuel being so hot it melts the plastic and rubber parts of the fuel injectors.
Last edited by Legend_master; 12-09-2012 at 09:29 PM.
I will describe new car's performance in one single sentence:
"I can remove my hands from the steering wheel and it won't produce the usual rattle noise"
I told my 14 years old daughter while we where in a red light "look, I can release the steering wheel" she asked "What did you do to the car that feels so different?"
Of course I also did the test of smelling the tail pipe and it doesn't smell like before. It smelled like fresh air!
I know the heaters I am using are pretty low power, so when the car is pulling more gas during acceleration, the flow of the gas colds the heaters down and the current draw increases. But at idle its a huge difference because the fuel flow is very little and it can be fully vaporized.
I started to modify my tune and I was able to reduce my Volumetric Efficiency (fuel tables) in the idling section from an average of 32 to an average of 25. and still working in the cruising section, but the numbers have been changed from ~45 to ~39 so far.
I didn't see a dramatic difference in my FuelUsed variable this morning though, (heaters need more power?) but need to finish the new tune first and then make further conclusions.
Power is nothing without control
From what I learned from school I remember that magnetism is a property exclusive of metals. Don't quite understand how a magnetic field can affect fuel.Originally Posted by Legend_master
An electrostatic field will certainly affect the fuel, but not magnetism. Haven't gone through the whole articles yet.. so I might be wrong...
Power is nothing without control
Yeah, we need to somehow prepare our car for higher pressures of the hot fuel contained in the lines.
With my 100C heater I noticed a difficulty for a hot-restart after I installed it, the fuel in the coil got hot soaked while the car was off increasing the fuel pressure.
The the usual "purge pulse" sent by the controller contained more fuel (same open time for the injector resulted in higher flow due to the higher pressure in the fuel line) so sometimes I had to press the pedal to re-start the car. It didn't happen before the fuel heater installation.
Power is nothing without control
Forgot to connect the coil for the fuel heater last night! So I ran today without the fuel heater, and it is logic that cold fuel is not good for the heaters and the vaporization process.
Power is nothing without control
That heater is also going to heat the incoming air as well as the fuel, thereby making it less dense. This could also explain why you are observing a rich mixture with the heater; there is less air (mass) getting into the cylinders. This might not be a bad thing though if fuel economy is the goal. Smokey Yunick did some work in the '80s on hot vapor engine induction that was pretty interesting and ground breaking at the time.
http://www.rexresearch.com/yunick/yunick.htm
C|
Mi smog test certificate.
When done with the new tune I am going to take another and compare. With this ultimate test, nobody can refute the results, whatever they are.
Power is nothing without control
Its actually an in line fuel vaporizer, and magnatizer. I don't really agree with the magnet thing, but the vaporizer is what intrigued me. I'm thinking if you ran metal lines from the fuel filter to the vaporizer, and then to the fuel rail pressure should not be an issue. Loving your project, keep up the good work.
Wow, those stories in the links are like horror tales! The guy that burned himself, then being in jail and persecuted all his life! The writer spent more time describing the poor life of the inventors than giving test data. It looks like the stories were written for those big companies to discourage others.
If I don't see a real benefit with the new tune, I will consider this fuel heater too risky for 3 or 4 MPG gain. It doesn't mean that I'm going to stop using the heaters, but I can use them to superheat the air only and not the mix. The problem I am noticing is a small fuel odor when I release the pedal. I assume the back pressure during a deceleration is expelling the vapors out through the throttle.
As Cygnus stated below, the heaters are doing their job by heating the air pretty high, that the air is changing its volume, so the car needs less fuel in consequence.
With this I can accomplish the goal set when I started the thread so I can relocate the heaters to the air intake tube... and test, and test again.
Power is nothing without control
However, the car runs really smooth. The quiet steering wheel says it everything even while warming up in today's cold morning of 35 F.
I don't know, maybe because I read the articles I got scared. I think we all have some degree of fuel odor in the engine bay, Do we?
Power is nothing without control
I think I know what to do to avoid this fuel odor that concerns me. I just read Smokey's link. The answer is there in the little turbines, but I'll take another approach.
Power is nothing without control
Not very encouraging news...
I am not longer measuring the fuel economy by the fill/refill method. I am using my highway miles vs the FuelUsed value method (which matches very close anyway). Once I get something promising, I will confirm with the standard fill/refill method.
When I set the Air/Gas heater to 80-85 C got 25 MPG (compared to the 19 MPG I got with cold air, it is 24% improvement!).
With the fuel vaporizer, Air/Gas temp set to 95-100 C, fuel tables reduced... got 22.6 MPG
There is something else going on that I don't understand. I know the heaters put more load to the alternator, but I hopped that the change in the efficiency would give me enough power to run the heaters and some extra for the engine.
I'm going to try to put some isolation in the intake manifold to avoid the fuel vapors to cool down while traveling from the throttle to the head.
Power is nothing without control
Just to make sure I explained myself correctly with my MPG calculations. This is a typical datalog chart of my daily way to work.
There is one 6.5 Miles section with no lights and light traffic.
I like to use that section because the car is fully warm already and is very consistent, the disadvantage is that its too short.
The great advantage is that I can open any old datalog and compare it vs my most recent actions for fuel economy improvements.
I found one configuration where mi car gave me 27 MPG. It was when I still had my dizzy. Since my current configuration is COPs in wasted spark mode, I know I am "wasting" some current draw to ignite one coil that is not needed. I'm not worried because that gain is already there, I just need to change to sequential ignition configuration to get 27 MPH plus what I can get with the air/fuel heaters.
Here is a typical chart and how I use it:
Power is nothing without control
There is an FI setup outlined in the book. In this version of gas vaporization, you heat the gas only to coolant temp, 180-190. The intake air gets heated up to exhaust manifold temp, which is quite a bit hotter. In this context, you should be able to do vaporization with OE injectors. Of course, it would be well to monitor intake manifold temps to make sure the intake isn't heating up the injectors too much.
Interesting. How well do you know your heaters? If I read correctly above, the heaters have a modest draw at idle, but the draw is variable depending on engine load. Also, their draw might be exponential. In other words, turning the heat up by x turns the draw up by 2x. The higher you turn them, the higher still the draw, in effect offsetting any vaporization savings. Are you able to monitor their draw while driving?When I set the Air/Gas heater to 80-85 C got 25 MPG (compared to the 19 MPG I got with cold air, it is 24% improvement!).
With the fuel vaporizer, Air/Gas temp set to 95-100 C, fuel tables reduced... got 22.6 MPG
Another potential issue with the heaters is that you're not really heating the mix across a wide area. You have a lot of heat for a very short distance. My guess is that you aren't heating the mix as much as you're cooling your heaters.
The heat coming off the exhaust manifold is pretty intense and is effectively free for the taking. You might consider trying a shroud on the manifold to conduct that heat.
I'm not sitting there with you, of course, so I am probably missing a lot. Just brainstorming over the internet.
I'm having a hard time gauging, but does it seem to you that you should be getting a lot more impressive results? I mean, the book cited 40 MPG just from heating the fuel to 180. That was for a '70s era V8. I'd think you'd be getting orders of magnitude better mileage by this time. On the other hand, you got some pretty impressive results (20%) simply heating your fuel a little bit. You had a couple coils going through the air cleaner. I don't think that ever got your fuel to 180 deg., so getting the mileage you did is impressive.
Dr_Snooz
"I like to take hammers, and just break stuff, just break stuff." - Beavis
1989 Honda Accord LX-i Coupe, 240k miles, MT swap, rear disc swap
Shop manual downloads available here: CLICK TO VIEW
I think I know whats going on.
I moved the IAT sensor to its original position, right in the neck where the fuel is injected. The average temperature there was 35-40 degrees C this morning.
So regardless of how hot the air is when measured in the inlet part of the filter, it gets dissipated during its travel through the filter case and through the fuel coil.
So the little improvement I saw was just the reduction of the air temperature enrichment part of the fuel equation, because I was cheating the computer making it believe the air was hotter than it really was.
I feel better because I have a clue now.
What I am going to do is to start a really serious insulation work from the filter case down to the intake-head area, plus a coil with coolant temperature around the TBI. The idea of this coil is to replace the OEM's coolant lines in the base of the carb.
The explanation for why I am seeing a reduction in the fuel economy is because it got really cold since Sunday, so the colder temp is taking its toll.
Last edited by Buzo; 12-12-2012 at 06:36 AM.
Power is nothing without control
Snooz, you are right in all what you said. I am not seeing impressive results because all the heaters I put are all low power. So they cool down with a simple change in the ambient temp or changes in the air (and fuel) flow during acceleration.
The 20% came from making the ECU remove the IAT compensation, and maybe a little bit from the O2 sensor "thinking faster". So its is not that it is more efficient now, but perhaps it was too rich before...
I of course want to keep going with the exhaust gas heater for the base of the carb, I just need to make it at least the same diameter so I don't add a restriction. Instead of trying to build it myself, I am going to hire one machine shop. I'm about to finish the drawings for that heater.
One good think of all these previous experimentation, is that using the UsedFuel method to measure the fuel economy has been proven to be accurate.
Step#1.- Repeatable measuring method - DONE! (-five- pages for the step one!)
Power is nothing without control
Yes air temp for me on a stock fi cars effects the mpg. I get the best at around 60 f. So spring and fall here. Its only 2 mpg difference but its repeatable.
Wp
1988 Lxi owner since August 1995
336k miles running strong!
Now running E85.
Oldblueaccord <<< MY YOUTUBE PAGE!
There you go.
Before trying to increase the power of the heaters, I am going to reduce the heat losses as much as I can. Just like we all do with the chillers at home.
Power is nothing without control
There is another variable you might have to consider too; the fuel mix. I don't know how it is where you are, but in the midwest US they change the composition of the fuel during the winter to make it vaporize better at colder temperatures. The downside is that the winter blend fuel contains less energy than the summer fuel. My truck for example loses about 2MPG on average in the winter.
For your purposes you can eliminate this variable by running your tests side by side using the same fuel. Just be aware that you may not be able to compare test results that were taken during different seasons.
C|
The expectation is if we can do this vaporization thing, The MPG must be so high that we should not be worried for +/-5 MPG.
So far we have proven that we will not get it working with a couple of 60W heaters. Its time for the next step...
Power is nothing without control
Just got a brilliant idea
I do have a cheap heat gun at home. I know it can reach ~750F because I use it for soldering, the question is if it will keep the power once the fuel is flowing through the heater.
I know it will work for Idle only, since it has to be connected to 110VAC. But the heat gun can be turned ON and OFF during the test and log the reactions of the engine.
If the heat gun is not enough, I can try with electric resistors...All I need is an indication this vaporization thing works before I mess with the exhaust tubes.
Power is nothing without control
An update on the Intake Air temperature.
I was able to rise the temperature in the inlet of the TBI to 70C by insulating the filter case from the ambient temp. I know it is hot for real because now I can make my engine to knock.
Logged a buch of short trips at different hours of the day. The only thing I need to do now is to log the data without the heater and compare. I can not compare to old datalogs anymore because my tune and the ambient temperature have changed.
Power is nothing without control
Yes fuel mix here does add into the equation. I just had a "gas pump" discussion on my fill up today with someone.
Buzo i would use coolant for your heat source its easy and safe. I worry about electrical esp. 110v. Draw back is coolant temp will be low on start up and limited to 200f or less.
Wp
1988 Lxi owner since August 1995
336k miles running strong!
Now running E85.
Oldblueaccord <<< MY YOUTUBE PAGE!
Supposedly coolant temperature is not enough for the level of vaporization we need. The book mentioned 750 F.
I did test my heat gun in my redesigned carb base, It reached 400F after 10 minutes even when I was spraying some water on it.
I had a huge cloud of water vapor in my garage as you can imagine.
Everything's ready for the testing in the car hopefully tomorrow.
Power is nothing without control
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