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Starting Timer from ignition on


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I have been tuning the IAT trim on my Nissan R33 GTR, and it follows what I've seen as recommended values (i.e. about -2% per 10deg C above 20). The problem I have is with plenum heat soak affecting a hot restart - when she briefly needs additional fuel not less to avoid lean stalling. If I set the IAT table to add fuel at zero throttle the CLL has to subtract a load when idling in traffic as the IAT gradually rises.

My plan is to set the IAT for normal running (i.e. subtracting from the fuel table), but use a Virtual Aux and Timer to switch a 4D fuel table adding more gas in the 60 seconds after ignition-on only when IAT exceeds 40 deg. The digital input for the ignition start (DI #2) is only active during cranking and once this ends the Timer cancels. I'm not sure what (if anything) I can use to initiate the timer (in conjunction with IAT) exclusively when starting up and at no other time.

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That's perfect! :). I had thought that, with the engine running normally (and hence engine speed constantly above 100 rpm) that the timer function would start, reset and keep cycling. I realise now that the timer activation condition will only be met with high IAT and engine speed starting below 100 rpm then exceeding it. Learn something new every day.


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