A poor man's fuel injection

[swheels]

Ok i've mentioned this in the other thread.

Well i think i've found a way to come up with some sorta fuel injection system.
Ok not really efi but damn close. Iguess i can call it EfC( electronically,fuel,controlled) uuuhhhhh yeah that's it.

I have the basics mapped out in my head as i would try to explain.Here goes: The standard carb will become or used as the throttle body.I will tap the top of the intake behind the carb for a spray jet of some sort.Then i will used the electronic trottle assembly from a pocketbike.I will also have to set it up somehow with a throttle cable also.(Haven't work that out yet)Then i will get or use a electronic speed control from the high dollar 1/10 rc cars.Reason being because if you get a good one they are very tuneable.Now the reason i need the speed control because this will control the electronic fuel pump and the speedcontrol WILL be controlled the the electronic throttle.So the more you twist the throttle then the greater the signal to the speedcontroller which in turn will signal the eletric fuel pump to pump more fuel. Gentlemen you follow i swear this will work and it will be more like a conversion kit.Now ofcourse the source of power will be li-po battery.Just running the system should be good for weeks.Oh also this is for motors with the inner rotor kit.For the motors with the charging systems you would use the standard electronics.The biggest challenge would be to get the cable setup and the speedcontroller in sync.

Now the benefits will be no more playing around with main and pilot jets.A more better fuel delivery and better fuel pressure.When you want to tune the motor.You can do it by making adjustments to the speed controller.If you slow the speedcontroller down you will slow the fuel pump down thus leaning out the motor.If you want to run it rich you just turn the speed up an the speed controller.It will send more power to the electric fuel pump to pump more fuel,BAM your running rich........You see you can get a more precise tuning affect.OOOOORRRRRR you can just change the fuel spray nozzle for bigger or smaller.thumbsup2

Now the spray nozzles i think i'm gonna make them.Cause i don't wanne be tapping some huge hole in to the intake.Wow had a thought i might be able to come up with a setup that will run 2 spray nozzles.1 for low speeds then the other will take over at high speeds.HUUMMMMthinking_smilie Well i'll focus more on the single setup first. Oh forgot to mention,for the fuel pump i plan on using one of those 12v inline fuel pumps for cars.
Now this setup to get everying i need mabey $200 to $300 and that's high ballin it.Which i think is a drop in the bucket considering how much the efi system from japan cost.
Now the RnD work well that's another story.

I will draw up a diagram and post some pics of the materials to give you guys a better understanding.

SO tell me what you think.........Have i finally went off the deep endcrazy_smilieLOL Give me your input fellas.I'm testing the waters in here first.If i hear crickets then i'll put it out to the masses.I think real simple so i'm not concern with calculating anything.So any input will be helpful.

OOOOH no co2 sensors and crap to mess with either.
Gentlemen i promise you if i get this setup going when it's done.It will be so simple to do.You'll nickname me the idiot.LOL

[Shooter]

Hey idiot!
I don't know anything about this sort of thing but your idea sounds pretty convincing.
I get the feeling Cam would have some knowledge in this dept.
IDK but you have ME sold.

[swheels]

LOL That's me.LOL yeah i would like to here his input also.Don't worry you'll get when i'm finished with the diagram.

[rene13]

:phat:

Is this the throttle you mentioned? http://www.akunar.com/THROTTLES.htm

It's the fourth from the bottom.

[swheels]

:phat:

Is this the throttle you mentioned? http://www.akunar.com/THROTTLES.htm

It's the fourth from the bottom.Yep those look like they can do the job.thumbsup2thumbsup2

[The Nutty Professor]

I understand the basics of FI and I think your system has a chance but it the fuel measurements I keep thinking about. If what you propose is correct why do they need fueling maps?

[swheels]

I understand the basics of FI and I think your system has a chance but it the fuel measurements I keep thinking about. If what you propose is correct why do they need fueling maps?Well on the larger scale and dealing with multiple cylinders.The over all system is designed to be smart and make the necessary changes it needs on the fly to keep the engine running in it's programed parameters at all times.Well most of the times.Oh and to keep fuel emissions down.

[Blitz$M.Inc.$]

so the carb is still used to meter the gas?
what feeds the nozzle you tap into the intake?
im thinkin a wrecked scooter with efi can be a donor

[rene13]

so the carb is still used to meter the gas?
what feeds the nozzle you tap into the intake?
im thinkin a wrecked scooter with efi can be a donor

I have been trying to hunt down a 125cc yamaha majesty EFI unit, but no go so far.

[swheels]

so the carb is still used to meter the gas?
what feeds the nozzle you tap into the intake?
im thinkin a wrecked scooter with efi can be a donorCorrect!......I was thinking to run the gas line right to the spray nozzle.I'm just worried about how much fuel pressure will build up in the line.Well the pressure can be regulated from the adjustment of the speed control also i think.thinking_smilie

[The Nutty Professor]

thinking_smilie S you sure know how to keep me up at night don't you moon1 I was reading that the injector has a small actuator inside or at least some do. I was think in that connecting that to the pick up on the IRK will signal the actuator when to open. The rest of your metering system will control the fuel pressure meaning the amount of gas sprayed into the throttle body/carb? You can't have a constant flow or you'll always have a flooded system or a rich condition no matter how you use the other parts. Right or wrong dunno

[The Nutty Professor]

I don't know if this is a find or not? I was looking for more scooters with FI and ran across this? Looks like a Chinese scooter company using FI on a lot of their bikes? If so :phat: If not oh well. What I'm thinking is the system in no way is going to be a direct swap nothing's that easy, but a hybrid of Swheels system and theirs might get it done pretty cheap.


http://www.toptom-vehicle.com/sdp/127372/4/cp-1081810.html

[swheels]

thinking_smilie S you sure know how to keep me up at night don't you moon1 I was reading that the injector has a small actuator inside or at least some do. I was think in that connecting that to the pick up on the IRK will signal the actuator when to open. The rest of your metering system will control the fuel pressure meaning the amount of gas sprayed into the throttle body/carb? You can't have a constant flow or you'll always have a flooded system or a rich condition no matter how you use the other parts. Right or wrong dunnoThat can be possible too.......Well when i start to develope the system i'm gonna work on getting the bike to idle first.(it's gonna take a lot of testing)Once i can get the idle squared off.Then i'll work on mid to top.I gotta try to find the balance while using the same size spray nozzle that will work through the whole rpm range of the motor.This is gonna be a tough task.I'm trying to keep it as simple as possible.If i can get it to work properly.

I don't know if this is a find or not? I was looking for more scooters with FI and ran across this? Looks like a Chinese scooter company using FI on a lot of their bikes? If so :phat: If not oh well. What I'm thinking is the system in no way is going to be a direct swap nothing's that easy, but a hybrid of Swheels system and theirs might get it done pretty cheap.


http://www.toptom-vehicle.com/sdp/127372/4/cp-1081810.htmlWell one of 2 things will happen.I get this system up and running or by the time i get my setup running they'll already be availible for the midbikes.LOLOLOLOL

[redryderaus]

Your idea will work in a basic sense S. However, Nutt is right in throwing up the need for fuel mapping. Even a carby has infinitely variable fuel delivery dependant on engine load (MAP = Manifold Air Pressure) and throttle position. It's not a linear "X" throttle position = "Y" fuel delivery.

1/ Low rpm/small throttle opening MAP is low (ie a vacuum) and the needle limits the fuel drawn through the jet.

2/ Low rpm/large throttle opening MAP is high (ie nearer atmospheric pressure) and while the needle can allow much more fuel to be drawn through the jet the lack of vacuum limits the fuel.

3/ High rpm/large opening MAP is low (vacuum) and the needle is wide open, so the engine is drawing maximum fuel through the jet to match the air flowing into the engine.

4/ High rpm/small opening MAP is very low (strong vacuum) but again the needle is severely limiting fuel through the jet.

There are obviously an infinite number of combinations of throttle position/engine rpm. A carby that is well matched and tuned to a particular engine will keep mixture within reasonable limits. But it will always be compromise over a lot of that range. EFI was created to improve on that compromise and fuel mapping in the computer is a large part of that.

Having said all that, I'm not ready to call you an idiot just yet! moon1 The early fuel injection systems were purely mechanical in action in that an engine-driven fuel pump supplied fuel at a pressure dependent on engine rpm, and injection was timed simply by a rotating plate with a hole in it. The size of the hole determined the time the injector was active. Most diesel engines still use this system to great effect. Of course, now even diesels use EFI as all so called Common Rail Diesel engines have electronic injectors and computers to precisely manage fuel delivery.

I like your idea of using two sprayers, one for low rpm but I'd have the second high rpm sprayer come in in conjunction with the low speed to supply the extra fuel needed at mid-high rpm/throttle. It's basically the same as a carby with a vacuum operated secondary barrel to handle high fuel demand. The reason behind that is it would be hard to get a single sprayer to work well across the entire range.

Cheers,

red ausflag

Today's "Did you know?" - Many early car EFI systems actually stopped fuel to alternate cylinders when you closed the throttle to save fuel??

[The Nutty Professor]

thinking_smilie So two injectors one for low to mid and the other for additional fuel as it pulls through mid and goes into high? Or something to that affect. After thinking a long long time (And again getting little sleep moon1) S your first thoughts about getting it working on idle are right along with Red and his two injector comment. I bet if it is working a idle you're going to have a bear when you wick it up, but with another injector that will make it harder but will probably handle the load. Now I have some reading to do on mechanical diesel FI and see how that works.

[swheels]

I totally agree with you guys.......For now i just want to keep it as simple as possible just to see if i can get it up and going.The system will change with testing and ofcourse i'm gonna need the input from all to help me cover all area's of the matter.

Here's a basic diagram(I wish it could be this simple).Remember just the basic.It's going to change as i find the necessary parts and pieces to make it work.
My goal is to try and keep it as simple as possible and to use parts that anyone can have access to plus putting it all together for a reasonable amount of money.Nothing over $300.00bucs,Hopefully less than that.I know that right there alone is pretty much a set up for failure.
Thanks for the input.I'm gonna need them.



I found a 12v speed controller on ebay for $45 brandnew.Not the ones i was using back in the day but i think it can be used.They have quite a few of them.

Well if i can't get it setup in a way that the average joe can do it.Then it will be a washout.

[The Nutty Professor]

looks do-able but what would I know bluelaugh I can't get a carb right.

[rene13]

I found this pic I hope this pic will help.

[swheels]

Yeah that's cool...

But i remember i found this awhile back.I don't know if you guys have seen this one.I thinks it's another avenue to look for.This might be easier to do.dunno
YouTube - Electronic Fuel Injected, ford EDIS igntion Briggs Stratton

[swheels]

Possible throttle body conversion???? It's a ski doo carb body.

This a kawasaki small twin engine fuel injected.
http://cgi.ebay.com/29hp-Kawasaki-Engine-ES-Fuel-Injected-for-Exmark-FD791D_W0QQitemZ110306287607QQcmdZViewItemQQptZLH_ DefaultDomain_0?hash=item110306287607&_trksid=p3286.c0.m14&_trkparms=72%3A1205%7C66%3A2%7C65%3A12%7C39%3A1%7C 240%3A1318

[The Nutty Professor]

I guess it comes down to time and a lot of looking around to find a system we can use lock-stock-and barrel thumbsup2

[The Nutty Professor]

Rise and be read

[Blitz$M.Inc.$]

looks like carbs are still king

[The Nutty Professor]

Yep! Even guys who work with the systems all the time when it comes to racing they prefer carbs dunno When you get F.I. right you can't beat it.

[Unproracer]

Im all for the fuel injection idea, Carbs work off the same princable toilets do...lame they are used so much. But i think you are getting in over your head on this one. Mechanical fuel injection was just that, mechanical. Rotors, pluggers, spinning discs and such. In a EFI system, a fuel injector is mearly means of delivering fuel, without a brain to tell the fuel injector when to pulse, how long to open, (miliseconds/miliVolts) and how much to open the coil, its gonna be untunable and unreliable. Fuel mapping is essential to all electronically controlled fuel injection systems with the exception of a linear rpm(only one engine speed). Not that mapping couldn't be done but even tuning aftermarket engine management systems on cars that have a KNOWN FACTORY fuel map to start with, tuning is very difficult, dangerous(to the engine) and expensive component and tuning time wise(gas analyzer and dyno most likely required.) Pretty sure variable rate fuel pumps are costly as well.

Hate to be a nay sayer and I don't know how much you ride your bike, but the cost of all this, the danger of grenading your engine, all the weight the supporting fuel pump, EMS, and electronics will be, plus any electric power loss to your ignition system(dont run your ems off a non charging battery....), should deter you from this... In addition an FYI i've had mine on a smog machine. The carbs do the job very well at all ranges these bikes can attain. And it seems to me a lot re-jetting occurs before proper tuning these days. Youll spend 1,000x more time on tuning if you equiped it with a EMS and fuel injection system and for one cylinder, its like using a 10ton nuke to swat a fly in all honestly. I dont even know if fuel injection is used on any single cylinder production bikes yet.... (probably wrong though)

I hate carbs but in this case they are more reliable, easier to tune, less expensive and do the job probably just as good as a tuned fuel injection system would on a single cylinder. ..... The only difference would really amount to better cold starts..thats it... Good luck though if you choose to pursue this man. Keep in mind modern fuel metering in a fuel injection system is done more by how long the injector is held open, not the increase of pulses or fuel pressure. That requires a brain to calculate input and output singles. Keep us posted though. I hope you can prove me wrong!! Good luck man. Peace..

thumbsup2

[stuntnx7]

Yep! Even guys who work with the systems all the time when it comes to racing they prefer carbs dunno When you get F.I. right you can't beat it.




only if you want to slow it down would you want a carb

[The Nutty Professor]

only if you want to slow it down would you want a carb

Tell that to King Kenny Roberts when he was racing his bikes in the 500cc Grand Prix. He was the first to go FI and got stomped by carbs. Like Pro said it takes a massive amount of brain to get it right. Here's a photo the OG's have seen a couple hundred times. I think "S" teased us with it first dunno If you have the money you got the FI system and it's for a single.

[stuntnx7]

Tell that to King Kenny Roberts when he was racing his bikes in the 500cc Grand Prix. He was the first to go FI and got stomped by carbs. Like Pro said it takes a massive amount of brain to get it right. Here's a photo the OG's have seen a couple hundred times. I think "S" teased us with it first dunno If you have the money you got the FI system and it's for a single.



well yea if you dont have the right setup anything will be faster...he proly had the wrong nozzles on it just like everybody that goes to FI for the first time

[swheels]

Im all for the fuel injection idea, Carbs work off the same princable toilets do...lame they are used so much. But i think you are getting in over your head on this one. Mechanical fuel injection was just that, mechanical. Rotors, pluggers, spinning discs and such. In a EFI system, a fuel injector is mearly means of delivering fuel, without a brain to tell the fuel injector when to pulse, how long to open, (miliseconds/miliVolts) and how much to open the coil, its gonna be untunable and unreliable. Fuel mapping is essential to all electronically controlled fuel injection systems with the exception of a linear rpm(only one engine speed). Not that mapping couldn't be done but even tuning aftermarket engine management systems on cars that have a KNOWN FACTORY fuel map to start with, tuning is very difficult, dangerous(to the engine) and expensive component and tuning time wise(gas analyzer and dyno most likely required.) Pretty sure variable rate fuel pumps are costly as well.

Hate to be a nay sayer and I don't know how much you ride your bike, but the cost of all this, the danger of grenading your engine, all the weight the supporting fuel pump, EMS, and electronics will be, plus any electric power loss to your ignition system(dont run your ems off a non charging battery....), should deter you from this... In addition an FYI i've had mine on a smog machine. The carbs do the job very well at all ranges these bikes can attain. And it seems to me a lot re-jetting occurs before proper tuning these days. Youll spend 1,000x more time on tuning if you equiped it with a EMS and fuel injection system and for one cylinder, its like using a 10ton nuke to swat a fly in all honestly. I dont even know if fuel injection is used on any single cylinder production bikes yet.... (probably wrong though)

I hate carbs but in this case they are more reliable, easier to tune, less expensive and do the job probably just as good as a tuned fuel injection system would on a single cylinder. ..... The only difference would really amount to better cold starts..thats it... Good luck though if you choose to pursue this man. Keep in mind modern fuel metering in a fuel injection system is done more by how long the injector is held open, not the increase of pulses or fuel pressure. That requires a brain to calculate input and output singles. Keep us posted though. I hope you can prove me wrong!! Good luck man. Peace..

thumbsup2All you have said i have taken in consideration.That's why i'm taking my time with this.Yes this will be alot of trial and error and painless hours of getting it right.I will be using a test bike and motor.
Plus fuel injection for a single cyclinder has been around since early 90's i believe.Aprillia was the first to develope this on a 2 stroke 50cc scooter.Now the current 4 stroke scooters carbs are electronic and mechanically controlled.That's what got me thinking about this.Iv'e had fuel injection systems on radio controlled nitro motors as small as .12 single cyl to .28's.

I basically through up a rough idea of my plan.I truely believe it will work and once i get all the components i need i'll begin putting it together and testing.All it is to me is putting in the RnD work and lots of it.
I spend a lot of time now on jetting, float bowl valves, and intakes and frankly it's getting to be a pain.Nothing ventured nothing game.
What i believe to be the challenge for me is trying to keep it simple as possible and using things that the average joe can get their hands on to do it.

A good lipo battery will run the system and be more than enough.After all i'm trying to develope it for racing purposes first.And i don't mind nay sayers that's why i put this out there to get different point of views from everybody.Even the smallest of ideas and scenarios

[cutlasskel]

Just saw this....
Would it not be possible to use something like the ignition system to fire the injector instead of the speed controller? You know use the current timing mechanism already on the engine for a dual purpose? Set the trigger point like 12 degrees of crank rotation before (or whatever it would take to run).

[Unproracer]

You could do straight pulse signal if you ran a variable rate fuel pump(not the same as standard fuel pumps), but still its gonna be a real bugger trying to tune something like that. In addition youll have to find a way to vary your current to the pump in relation to your accel, and off gas conditions. Keep in mind the fuel injector will be still be firing when your off the gas if its running off your RPM speed unless you address this issue. And a fuel pump is gonna require alot more current then a lipo battery is gonna be capable of handling IMO. Good luck.

[swheels]

Yeah that's why i was gonna use the speed controller to control the fuel pump.Then come up with a way to control the speed control with the throttle while also using a cable to open the throttle body.Then having to get this all in sync.

Rene has put some throttle control from akunar.But now that i really looked and them.I pretty sure there not variable rate.Just on off to control the carb with electric chokes.
Now on the scooters even though the choke is electronic.But the barrel on the carb is controll electronically also.The cable on the throttle actuates a manual pump on the carb.So i'm basically substituting the manual pump for the electric pump and a variable rate speed controller and the barrell of the carb/throttle body will be controlled by the cable like normal.Then instead of the jets the fuel lines will run directly to the spray nozzles.

[Unproracer]

If the carbs throttle is controlled electroniclly, then its got a TPS inside the sensor on the end of the throttle plate. See if you can tap into it. It should be rated in Volts, probably either .01v to 1v or .01 to 5v system. That or get a throttle position sensor off a car and adapt it. That or use the coil signal from the crank sensor.

[The Nutty Professor]

Here's a mechanical FI system:

http://www.diagnostic-assistance.co.uk/mech_inj.htm

Before the E in EFI it was basically a MFI system no electronics really. The air senor was a, for want of a better description, hot wire that was variable when it was cooler or hotter. More air flow cooler, less hotter and that was a very simple signal to the potentiameter. Bosch I believe was the master of this simple but very effective system. "S" isn't trying to re-invent this sytem just make it possible for someone to go to their "junk" bin and put it together bluelaugh There is no better system than one you can say "I did that".

[stuntnx7]

Here's a mechanical FI system:

http://www.diagnostic-assistance.co.uk/mech_inj.htm

Before the E in EFI it was basically a MFI system no electronics really. The air senor was a, for want of a better description, hot wire that was variable when it was cooler or hotter. More air flow cooler, less hotter and that was a very simple signal to the potentiameter. Bosch I believe was the master of this simple but very effective system. "S" isn't trying to re-invent this sytem just make it possible for someone to go to their "junk" bin and put it together bluelaugh There is no better system than one you can say "I did that".



my rons racing toilet is mechanical no electronics and after you get it setup theres minor changes you need to do from hot to cold days

[The Nutty Professor]

my rons racing toilet is mechanical no electronics and after you get it setup theres minor changes you need to do from hot to cold days

How about some photo's of the system? The toilet you can aaahhh....leave out. That's TMI.

[boonacka]

I have an injector driver that drives two injectors based on rpm. it was a piggy back to a turbo system i had years ago. theres a digital display and controller that lets you adjust the flow of the injectors at whatever rpm setting. fine tuning would be a b!tch and was a B1tch thats why i took i toff.

[swheels]

I have an injector driver that drives two injectors based on rpm. it was a piggy back to a turbo system i had years ago. theres a digital display and controller that lets you adjust the flow of the injectors at whatever rpm setting. fine tuning would be a b!tch and was a B1tch thats why i took i toff.Did you have that system on a mini Or your automobile?

[boonacka]

auto.

it also had a built in turbo timer function. i was also wrong with my description earlier as it took boost/vacuum readings as the adjustment factor. not rpm

i believe it was made by turbo specialties. nothing extravaggant but it worked to an extent.