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Old Mar 5, 2020 | 01:45 PM
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Default Fast efi

Received my FAST EFI for my C3. Should go in next week or so.


Ok
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Old Mar 5, 2020 | 01:45 PM
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Old Mar 5, 2020 | 02:50 PM
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Please keep a good log of your progress. I'm thinking about doing the same with mine and would love to see how easy of a process it is. Thanks!
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Old Mar 5, 2020 | 04:31 PM
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I'm not bashing the Fast system at all but mine has been a problem. I have the 2.0 on my Cobra. Easy install but it just has never run at low rpm correctly and now it is loading up so bad the car stalls. Plugs are black and it is running pig rich.
I have run a few injection systems on different cars and this by far has been the most troublesome. I have run a Massflo, Fitech, older Holley system and a slightly modded LS3 and now an LS7 injection so I'm not a rookie at this. Let me know how your system runs after about 100 miles of learning. Mine ran great for about 1K miles.
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Old Mar 5, 2020 | 06:05 PM
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Originally Posted by Gordonm
I'm not bashing the Fast system at all but mine has been a problem. I have the 2.0 on my Cobra. Easy install but it just has never run at low rpm correctly and now it is loading up so bad the car stalls. Plugs are black and it is running pig rich.
I have run a few injection systems on different cars and this by far has been the most troublesome. I have run a Massflo, Fitech, older Holley system and a slightly modded LS3 and now an LS7 injection so I'm not a rookie at this. Let me know how your system runs after about 100 miles of learning. Mine ran great for about 1K miles.
Any thoughts on the cause? What has tech said? Are you running a large cam? I have had some concerns with running a large cam with one of these systems due to the lower vacuume. My understanding is the engine with a large cam should have no problem it the vac is 8 or above.
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Old Mar 5, 2020 | 09:33 PM
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Is it EZ-EFI 2.0?
I am running EZ-EFI 2.0 to control my RamJet 350 with a locked MSD Distributor.
I have the ECU under the passenger side dash. Make sure you run good grounds and wire it as directed by the instructions. My MSD box is in the engine compartment under the passenger side fender side. Minimize the control leads that run next to the spark plug leads otherwise you may end up with the multiple troublesome IRM codes.
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Old Mar 5, 2020 | 10:26 PM
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The Cobra is a very small car. I-have the ECM is behind the passenger seat and the wires are away from everything. My MSD box is behind the dash away from most everything. Ground wires. Ihave run an extra few of them. Yes it is the 2.0 system which. I was lead to believe was a better system. Fast tech support is terrible at best. Just google it and. I-have tried multiple times to get assistance to no avail. I have locked out my MSD dist and it has been timed a number of times perfectly. I’m kind of at my wits end. Nobody wants to seem to take on a system that is having problems and need tech support, just pass it on to the next guy.
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Old Mar 6, 2020 | 09:52 AM
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I have heard that the EZ-EFI is picky. I have XFI 2.0 and it runs pretty good. Getting it tuned was a pain though. Very few tuners seem to do FAST. Holley is better supported. If I was going it again, I would probably go Holley just for the USB interface. The FASXT XFI uses a USB to serial adapter and I only have one old computer that will run the software. Very frustrating.
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Old Mar 6, 2020 | 04:41 PM
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Direct grounding of the computer to the battery is important. Any 'junk' in the electric lines can cause computer problems; it's not as simple as just hooking up a light or motor to 12 vdc.

If the computer ground is just connected to 'frame metal', that could be your problem.
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