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Electronic fuel injection- CV carbs to TBI

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RempageR1

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I don't know the software, but that seems something very-easy to program to work every-other cycle.
The challenge would be to find out what cycle. Because without knowing which is the true ignition stroke, it would start 50% of the time and be wrong the other 50% of the time.

Well I'll add my 2 cents to this really old thread. While the F.I. sounds great as there is no more adjusting the carbs, the FI systems has the same issue. I had the Wild Bro FI on my bike for a while and I always had to travel with a tablet to do adjustments. You need to drill and weld a bung on your exhaust for an O2 sensor. You need to drill and install a fuel pump on your gas tank. You will need to dyno the bike to set up the base configuration. The FI system ran really rich and was hard to get that magic 14.7 -1 ratio. I never was able to get a nice curve but generally it performed pretty good. I'll see if I can find the dyno but I was able to get 120 hp out of with a kerker 4-1 with the small baffle. Unfortunately, unlike your car, this was not a set once and forget system.
I`m wondering how you set it up. From what I read on other forums by birdoprey, this is the firing order of the Vmax:
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*Cyl #1 fires, then the crank rotates 70deg
Cyl #2 fires, then the crank rotates 110deg
*Cyl #3 fires, then the crank rotates 70deg
Cyl #4 fires, then the crank rotates 110deg
Cyl #1 fires, then the crank rotates 70deg
*Cyl #2 fires, then the crank rotates 110deg
Cyl #3 fires, then the crank rotates 70deg
*Cyl #4 fires, then the crank rotates 110deg
*Cyl #1 fires(back at the start)

The "*" indicate when that cyl is TDC on its compression stroke(power stroke)
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So next to squirting only on the correct stroke, you have to time the fuel injection correctly per cylinder. Since the V4 is configured in 70 degrees V instead of 90 degrees, the injection moments have an offset in timing as well.

Were you able to configure both correctly with the Microsquirt? If not, that might be reason why you ran rich and weren't able to make it run autonomously as it in theory should be able to.

Thanks!
 

gentsvmax

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A few years back I started conversation with Jack Flemming at roadster cycle, watched every video I could find and bought the plans from him to begin the F.I. build. The planned parts list among alot of other things requires the bunged exhaust for sensor, tip-over fuel shut-off, you decide on internal or external high pressure fuel pump, throttle position sensor GM, inline water temp sensor Ford, Ford 302 injector's and an extensive read about choosing a Megasquirt brain module, either you buy and assemble as a kit, like a Heath kit or a little more expensive module sold ready to program. Both like the fuel pump and water temp sensor are going to be a challenge to find room for to mount. There are quite a few more ingredients can't access the plans as I write this. Jack would NEVER,EVER offer any program advise, he told me "my success as a winner would be based on research, research and more research, dedication and perseverance". He stressed the possibility to quickly burn up a motor with a lean condition programming . LOL every time I spoke with him he would raise his voice saying "Do your home work!". I have a shop here called Quality components thats ready to machine the injector nozzle adapters and plates per the plan drawings for $750,
350 more for the big brain and whatever else Iv already got into the misc. parts doesnt seem like much at all if I could have the performance of the Roadstercycle Vmax( new version) with dual exhausts doing burn outs WITH a 300 wheel and tire!
I just got discouraged about the programming challenge, lack of info and the very real possibility of frying an engine.
Despite the floggings from the mod monkey.
I like the resurrection of the topic and the discussion in hopes of some new info on the possibility of F.I. for the Gen 1 Vmax before fossil fuels are banned.......
 

02GF74

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So the ignition system is wasted spark?.
How can time the injection without knowing crank position ie having no toothed trigger wheel?

I'm guessing you need to figure out rpm then calculate the delay after an ignition coil trigger when to inject?

And how would you know how much fuel to inject without a throttle position sensor? Use the vacuum sensor?

I need to read up about megasquirt,...
 
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RempageR1

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So the ignition system is wasted spark?.
How can time the injection without knowing crank position ie having no toothed trigger wheel?

I'm guessing you need to figure out rpm then calculate the delay after an ignition coil trigger when to inject?

And how would you know how much fuel to inject without a throttle position sensor? Use the vacuum sensor?

I need to read up about megasquirt,...
A toothed trigger wheel at the crank would give you precise timing, but again it wouldn't know in which cycle the cylinders are. So you probably need to add a cam-sensor. I also read that you might be able to use the MAP (vacuum ) sensor since the manifold pressure drops at the moment fuel is sucked into the cylinder.

But again, I`m looking to see if there is anyone that has actually been able to get it running properly with the correct timings. Since I have the Ignitech, I`m not interested in doing the ignition off of the Injection module, so trigger wheels etc are not required at this time.

Addition: This comes directly from the Microsquirt hardware guide:
For fuel-only installs it is possible to obtain a tach in trigger from the negative terminal of a single coil. Note that
this won't work well on a wasted spark setup[...].


So that specifically states the setup`s I`ve seen so far on the Vmax are suboptimal.
 
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02GF74

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As you say, with wasted spark, the fuel will be squirted in on the intake and power strokes.

Potentially the system could squirt on every other cycle and then either engine runs great or like a bag of nails. If the latter, then the system switches to squirt on the other of the wasted spark ignition event.

I'm not sure if the vacuum gauge would react quickly enough, maybe it will.
 

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