anyone any expiereance with air fuel ratio graphs

Associate
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i had my dads fancy computer doo dah set up to my spitfire tonight and checked the afr on it ranging from 800rpm to 3500rpm, got a kinda unexpected result, heres the graph.
main.php


it basically starts at 22.39 afr then goes down to 12.9 afr at 3500.

now this tells me its running super lean then goes to rich on acceleration.
 
Caporegime
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That's a Innovate LM-1.

Probably needs calibrating via a free air calibration. Lambdas voltage doesnt change much either which is odd. Sure it's set up properly?
 
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hmm maybe i need to re-calibrate yeap its the innovate lm-1.

the voltage wouldn't change as it blew the cigarette lighter fuse in my spitfire to i had to use the external power adapter.
 
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right re-calibrated and got a much better readout, still not too sure what i can do to improve it.
here is the new readout.
main.php


the peaks are 1,000 - 2,000 - 3,000 and 6,000 rpm

as you can see at 6,000rpm the engine is running perfectly.
 
Soldato
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Mattius said:
engine speed is just done by matching the revs to the time.

voltages won't change its being powered by an charger as my car won't power it.

Hes on about the lambda voltage to show the AFR not the power supply voltage.

An engine wont run when its that lean, i suggest you make sure your calibrating the sensor correctly.
 
Soldato
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main.php


There

and 1.46 lambda is 14.7 x1.46 = 21.5 ish on the other graph.

i take it the other 5 outputs arn't being used and thats whats confusing matters.

Id throw that manual away if its suggesting a lambda of 1.4 is okay.

You want lambda of 1 at idle and cruise and about 0.85 at full throttle.
 
Caporegime
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Mattius said:
yeah im only using the one input. hmm back to the drawing board with the engine tuning then.

Sounds like you need to do some research.

You need to understand what you are doing before even thinking about tuning an engine
 
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