Fuel Injection Fabrication - Comments

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BraneDeadX

New Member
#1
#1
I wanted take some photos of what Iam trying to build from the grond up. I had a sudden spin off from my EFI - Supercharged motor, and at the last minuite came up with this simple setup.

www.redneckcustoms.gotdns.com/efi/101_0270.JPG

www.redneckcustoms.gotdns.com/efi/101_0271.JPG


What you are looking at is a normal carbrator to GX200 series motor intake port, I I machined up a fuel injector boss that can easily be welded (now) to the intake manifold. My first attempts were little bit more something eles.

I then took the throttle body I made and bolted it to the manifold, it came out look nice, not as heavy as I thought it would be, the hole bore from TB, to the manifold flange is 1.080".

I wish I had something to test this on, its nearly a ready to go package :p hehe.

Next I need rebuild the superchargers exit port flange and what not.


www.redneckcustoms.gotdns.com/efi/101_0276.JPG

Another shot of the "NEW" intake manifold (thicker walls, easy weld)
 
spacecoast

spacecoast

Member
#2
#2
Have you considered motorcycle throttle bodies? Injector boss already equipped, tps already equipped. Finding a small enough bore might be an issue, otherwise tip in would be a bear. Going Megasquirt? Your bringing back memories. Nice work thus far, keep the pics coming in.
 
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BraneDeadX

New Member
#5
#5
Hmm not sure what ECU to use at this point, I can snatch a megasquirt and build it up for 20 bucks no problem, I still have my old EFI board I built ages ago that I can bring back to alive.

It will be very simple to control the injector, just monitor the analog 5 volt output off the MAF and monitor the RPM, use a 2d lookup table be done with it. I plan to use engine temp and throttle position later on for enrichments, but motor this small might not need them.

Hopefully today I can machine up a new flange for my smog pump / intake manifold adapater. Does anyone know where I can find some 1.25" rubber/silicone hose? and I need find a decent K&N Style airfilter :)
 
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BraneDeadX

New Member
#8
#8
Hmm that sounds better yet, I have no expierence with mech. FI , I know lot of bosch back way when used it, I found intresting site that talks about how the system works.

Going this way would be better then adding more complex parts to the motor, keep it real lean and simple.

I wonder how hard it would be to fabericate a system that worked off just the motor it self instead of electronics, does anyone know anything about this type of fuel injection?
 
rudedog

rudedog

New Member
#11
#11
Well...........................................


How about you eliminate the MUSIC so we can actually hear the engine, okthnxbye.:thumbsup:











As for the revs, is there a rev limiter built into whatever software you're running........as with just about every other fi setup out there??
 
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BraneDeadX

New Member
#12
#12
hehe that music is awesome man!

the only software i was running was my two fingers taping the wire to battery terminal hehe.... iam thinking the valves are floating, what u see me try attempt to do was increase the fuel pressure see if it would lean out or not.


i really need stop being lazy and build up a controller for it, maybe this week :)
 
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DANGERFIELD3rdI

New Member
#14
#14
It sounds to me like the motor is starving for gas, maybe you should install an injector on the head instead of in the intake, is there a gasoline build up in the hose? What are you trying to accomplish here anyway, small motors run great just the way they are, fuel injection is just something that will only add confusion to mini or a gocart.
nick
 
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BraneDeadX

New Member
#15
#15
well what you cant see me doing in the back ground is tapping the fuel injector wire to the battery, not exactly correct way to shoot the fuel in....

As for adding "confusion" (or asking why do it in first place) to my motor/bike/gokart , All I have to say is ohh well, when my smog pump supercharged hybird chopper flys past yeah on the straight away, then you can figure it out :p

hehe...
 
65ShelbyClone

65ShelbyClone

Well-Known Member
#16
#16
BraneDeadX said:
I wonder how hard it would be to fabericate a system that worked off just the motor it self instead of electronics, does anyone know anything about this type of fuel injection?
Click to expand...
Unfortunately I do not know exactly how the major mechanical injection systems work, but you might find something on the Hilborn, Enderle, or Kinsler websites.

At first glance they appear to work like a throttle-dependent carburetor.
 
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BraneDeadX

New Member
#17
#17
I just ran my little video clip into sound forge and did some low-pass filtering to it.

I selected part of the motor running wide open and wrote down the length of sample and how many times i peaked the sound clip, I came up with the motor was running at 2600 rpm.....

Does anyone know if the stock clone motor valves will only go this high?


Iam thinking of slaping the 26lb + 1.2 rockers in see what happens :p

**edit*** I should consider that any noise made from the motor running is going be twice as fast on the crank then the valves opening, Its hard think this motor is turning 5000rpm, even with the weight load on the crank from stator. I didnt think to consider the valves running half speed of the crank shaft hmmmm....

Would make more sense at that rpm the valves would for sure float, ill have to hold back off blowing up this motor until i get something with at least a wheel behind it heh...
 
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65ShelbyClone

65ShelbyClone

Well-Known Member
#19
#19
A normally aspirated engine probably won't have the top distribution block and nozzles. A turbo or dry blower wouldn't need them either, but many of the GM type Rootes blowers need fuel going through them for cooling and sealing.
 
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BraneDeadX

New Member
#20
#20
intresting, that stuff is over my head! i really have no idea how that all works togeher, even reading the bosch stuff is inresting in its self.

Even tho, computerized FI is always the best way to go, go figure why auto makers use it instead of any other type of system.

I had some time this week to dust off my old EFI board and plug her into my computer, I still had the last code i was working on from who knows when? I had fuel/ignition map with some interpoleration code in it. I was pluging in some fake MAF/RPM values into the code see the output result, stuff works great! all i need to do is add some timers and toggle on/off an output for injector. Should be intresting to bring this stuff back alive :)
 
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