Batch injection with siamese ports, injector timing

Converting To Delco ECU From Carby Or Other Injection Systems
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delcowizzid
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Re: Batch injection with siamese ports, injector timing

Post by delcowizzid »

Is the v6 trigger wheel on the front of the balancer spinning the wrong direction? The ignition module is probably commanding all sorts of weird timing the 3x slots are all different window sizes
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VK_3800
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Re: Batch injection with siamese ports, injector timing

Post by VK_3800 »

Pretty sure its just spaced out with the sensor behind it so spinning in the correct direction. It really didn't seem to run all that bad once we tweaked the injector rate, considering its otherwise a standard V6 tune. Haven't had a chance to do anything else with it yet, just pointed the owner to the forum so he could get an NVRAM module and cable/comms module.

All this stuff with the siamese ports is more pre-emptive than anything, we're not chasing a specific fault (yet). I'm thinking it can't be too hard to switch the reference signal on at the right time based on a simple crank position sensor (I don't think stroke matters with the right crank position) with a basic latching circuit, kind of leaning this way if the ignition module doesn't do that already.
vlt304
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Re: Batch injection with siamese ports, injector timing

Post by vlt304 »

set up tbi on the memcal it will fire the injector every ignition pulse and should not care what stroke you are on
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Re: Batch injection with siamese ports, injector timing

Post by VK_3800 »

That's nice and simple, could be a good option especially with only three injectors. Thanks
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Re: Batch injection with siamese ports, injector timing

Post by FBUTE »

Yes trigger wheel is mounted as per factory orieintation.It is bolted onto harmonic balancer and I rotate it to get the factory Grey motor timing marks to line up.The CAS sensor is the factory VN one as is the TPS.Great to see the ideas coming through
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Jayme
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Re: Batch injection with siamese ports, injector timing

Post by Jayme »

another option to think about is to try falcon barra injectors. when they squirt, they have 2 fuel streams out of one injector so each injector sprays onto both valves. , so if you are lucky, you could position it so that it sprays the fuel with one stream towards each port... maybe could help get the fuel equal. I had huge problems in a datto engine with one injector feeding into 2 cylinders because the injector would spray onto the manifold wall, then gravity would drag all the fuel towards one port and not the other. in the end redisigned it with 4 injectors instead of 2 lol.
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Re: Batch injection with siamese ports, injector timing

Post by Holden202T »

the problem with the grey motor though is the head only has 3 small holes for the inlets, so they might not even work like this unless the injector is almost in the head itself!
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Re: Batch injection with siamese ports, injector timing

Post by Charlescrown »

Ahhh memories. Even looks the original colour.
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Re: Batch injection with siamese ports, injector timing

Post by VK_3800 »

Yeah not overly familiar with the port design myself, I'm a bit more of the red motor era. If they are true siamese ports you'd need to do a bit more than just point more fuel at the right valve, timing will be crucial. Injector position in the manifold is pretty good but it won't be directly aimed at the valve.

I'm liking the TBI idea at this stage, could be a pain with too much injector but having already reduced from six to three it might just be the magic solution. Hoping that setting the memcal netres will trigger this, but can still configure $12P for 6 cylinder so the RPM readings will be correct?

Failing that some sort of simple latching circuit to trigger the start of the reference signal has to be possible, in this case there's enough symmetry in the firing/port order that stroke is not important so would only need to be triggered by crank position.
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Re: Batch injection with siamese ports, injector timing

Post by vlad01 »

2 injectors per port and later MAF ECU with sequential injection?

There maybe even something you can do with a 424 and bank injection with 2 injectors per port one from each bank of drivers.
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