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Default JB4 meth cut partial throttle & WG control for flash tune - 10-21-2018, 10:34 PM

Hi Guys,

Any way to reduce METH cutout on partial throttle or make it less aggressive, it keeps cutting out flow if throttle position goes below about 50% when manifold boost is still >20 psi

I understand why this was done, to prevent misfires due to flooding the system with fuel on part throttle or TC event, however I am a bit concerned for my 11:1 CR engine I would feel more safe if I could ensure that the meth always flowed when manifold boost was > 15 PSI for example

I like to drift a little and I do not feel comfortable because this requires a lot of part throttle high boost high RPM, where the meth is basically cutting in and out all the time at high boost

attached are 3 logs, one is a normal 3rd gear pull, and the other 2 are examples of part throttle issues, in one there is boost spike almost 30 PSI... as throttle closes, and manifold pressure is still at 21 PSI, and no meth flow, is a bit risky no?

Also I want to try to use JB4 for WG control but not for boost control, but when you put in all 0 in map 6 it disables any WG / FF / PWM control in MAP 6 so it seems hard to use JB4 for WG control with a flash tune right now?, I would like to take away a bit of WG actually to prevent the throttle closure I get sometimes and also hopefully prevent over-boost like you can see in that log below, by apply negative offset then add back in DB, the the JB4 can reduce WG to better control boost under some of these conditions

120i, JB4 +EWG, BMS METH CM3 + CM7, **, CP, BMS Intake

Map 6 with all 0, so its map 6 with just the stock boost as I am running stage 2 TMC flash and the stage 2 boost target is plenty of boost
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Default 10-22-2018, 08:28 AM

You're getting boost and flow mixed up. Pressure is a form of resistance, not flow. So you're not flowing that much air for the methanol to be needed, just take a look at AFR.

Log looks good, set FUA to 10 it will help with the throttle closures. Update your Jb4 firmware too.
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Default 10-22-2018, 10:40 PM

yah the AFR dropping would suggest there is less air flow, even with the same manifold pressure there is less air going into the cylinder, certainly that could happen via the valve train control as well

too bad there is no MAF reading in the log to see the air mass flow

can you confirm that the FUA bias will apply in map 6 with all 0 for the target boost? Also can you help to explain why the DB does not work when I have 0 for the target boost, for example what if I just put in like 0.1psi here would that be way to enable the DB control without increasing the target or only slightly increase it?
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