Power falls off at 6800 RPM 18 psi 2871R

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04-04-2012, 12:13 PM

#21

Braineack

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Quote:

Originally Posted by 18psi

am I reading that wrong?

yes

04-04-2012, 12:14 PM

#22

Stein

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Quote:

Originally Posted by Braineack

yes

Actually no.

Quote:

Originally Posted by spestis

Good call, the chart was incorrect. I posted the correct timing chart above. I forgot my stock ignitor box was gutted. I have not worked on my car in around 3 years.

04-04-2012, 12:18 PM

#23

Braineack

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whatever homey.

04-04-2012, 01:34 PM

#24

Faeflora

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Quote:

Originally Posted by spestis

Update: I did find the problem. The dynos RPM numbers are off and the power drop signature is the Link ECU hitting the rev limit (at 7200 rpm). The Link drops the timing to 0 deg. just before the rev limit and that is why the power falls off. The dyno was off by several hundred RPM.

Wow. Good job. Mystery solved. Shiit nugga

i was hoping for something less silly though

04-04-2012, 01:36 PM

#25

JasonC SBB

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Lesson for those who said "restriction" or "exhaust" or "ignition breakup" or whatever.

Restrictions do not cause a very sudden drop like that. Ignition doesn't also suddenly break up very consistently at a specific RPM.

When I first saw the graph "dyno smoothing" came to mind, and then "soft rev limiter". If the car hit a hard limiter during the pull, it tells me the smoothing algorithm on the Mustang dyno is aggressive and poor.