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04-08-2020, 10:45 PM | #1 |
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Fast xfi rpm issue
Fast xfi, analog 7al2, fast dual sync dist. My autometer tach is roughly 500rpm less than what fast data shows. Fast at idle shows 1100 while tach is around 600. Is this normal or if not, what is the fix. I honestly thought I had a low reading tach before I put on efi, just now I have another reference that should be super accurate since its dual sync
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04-09-2020, 08:34 AM | #3 |
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Re: Fast xfi rpm issue
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04-09-2020, 09:25 AM | #4 |
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Re: Fast xfi rpm issue
Where are you picking up the tach signal?
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04-09-2020, 09:57 AM | #5 |
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Re: Fast xfi rpm issue
at the 7al2 box, tach terminal
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04-09-2020, 10:34 AM | #6 |
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Re: Fast xfi rpm issue
Is there an unused tach wire on the FAST harness? If there is, it would be worth trying before changing the tachometer.
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04-10-2020, 12:12 PM | #8 | |
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Re: Fast xfi rpm issue
Quote:
That was not the first Autometer tach I've had that was off but was the most inaccurate I used an MSD ignition tester to fire the ignition and it reads rpm right on the tester. It can be used to test many items rpm related including a tach.....
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Rich Biebel S/C 1479 |
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04-12-2020, 05:27 PM | #9 | |
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Re: Fast xfi rpm issue
Quote:
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