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jpnovak jpnovak is offline
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Join Date: Apr 2000
Location: Austin, TX
Posts: 7,091
Congrats on getting to the point where you have a running and driving car. Let the fun begin. Prepare to fill your gas tank a few times as you work through tuning.

Cory has it correct. You need to investigate your VE table scaling. Here are a few guidelines...

Max MAP value should be about 5 kPa above your max boost level.
Min MAP should be what vacuum your car pulls off throttle about 3K rpm. I would start with 35-40
The MAP bin distribution will depend on how your car builds boost. you will likely need less resolution above 120kPa. More resolution in the mid-throttle range.

Max RPM should be redline
Min RPM should be about 50-100 rpm below your idle speed.
RPM resolution for Fuel will need fine resolution (small steps) off idle and fine resolution in your boost transition area. Anywhere you have a "non-linear ramp" in the table gets more resolution to accurately fit the curve. Once into boost, the fuel curve will flatten out.

I suspect that you are ramping through boost from 1700 to 3000 rpm. This is where you want finer step size so you can tune it out. Should not be hard... \

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BTW, Once the car runs and drives reasonably good you should spend some time to scale your fuel and spark tables appropriately. This will save headaches later on and allow you to tune with the right resolution and spacing as early as possible.

If you find that you run out of VE table room, meaning that you hit max fuel value of 255 (digital limit) you can increase Req_fuel value and then scale the table down by the same percentage change. I like my VE table to max out around 230 at full fuel delivery. Yes, it does not accurately depict real VE value but who cares. What it gains you is granularity of tuning idle - especially important with larger injectors flowing little fuel.
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Old 07-12-2017, 09:53 PM
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