Rx7 550cc Turbo Injectors Idling Problem - Miata Turbo Forum - Boost cars, acquire cats.

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Old 12-05-2015, 01:05 PM   #1
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Default Rx7 550cc Turbo Injectors Idling Problem

I've got myself a set of Rx7 FC Turbo 550cc Injectors for my 1992 Mazda Eunos 1.6 Turbo.

Fitting them was straight forward and I adjusted the required fuel to a flow rate​ of 550cc which gave me a value of 4.9(2.45ms)

Driving the car was no problem, the map was pretty close to the 1.8 254cc injector map I had set up

However the Idle is extremely poor, it seems to idle for a second and stalls

Would adjusting my​​​ Injection Dead Timing to 1.2-1.5ms correct this and what has everyone else done to sort this problem out?

This is the photo of my screenshot

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Rx7 550cc Turbo Injectors Idling Problem-80-rx7_20injectors_zps6dbdhor9_aa3d7e8432ae10d6697d7430e46df41483cb87af.jpg  
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Old 12-05-2015, 02:04 PM   #2
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What's your idle afr? Increasing the dead time is just increasing the fuel amount and screwing the rest of your map up, and making tuning a headache.
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Old 12-05-2015, 02:18 PM   #3
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Its set to 14.7
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Old 12-05-2015, 03:37 PM   #4
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But what is it actually.
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Old 12-05-2015, 04:03 PM   #5
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You aren't going to be able to idle those old slow injectors at 14.7 on 1.6 batch injection. Your calculated pulsewidths are probably smaller than your deadtime values near idle and therefore you aren't getting consistent fueling. Near 550cc injectors your idle PW is going to be near 2.0ms on sequential. If you run batch, you have two squirts per cycle, so you get two 1.0ms pulses which are lower than deadtime.

Drop down to 13.8 AFR or upgrade to sequential, or injectors of this century...
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Old 12-09-2015, 05:53 PM   #6
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~1.2ms is where my rx7 440s were happy.
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Old 12-10-2015, 04:54 PM   #7
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I ship world wide
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