High Ve values- turbo car

Hey guys, just fired up my first turbo build. Right off the bat, I am having to input what seems like really high ve values (70+ in idle regions) to get this things Lambda error in check. The ve values in the lower map region are much higher than stock, which is odd, because this is a stock engine despite the turbo. Is this normal to have such high ve values?

A quick run down on the setup..

81 buick regal
stock 01 5.3
4l80e
2005 p59 ecm running DBC and flex fuel
converted to 3 bar
ZR1 map sensor
ID1000 injectors at 58 psi base
Boost referenced FPR
pt7675 turbo

What fuel is in it? Closed loop commanded a/f indicates something around 58% ethanol per the stoich a/f table. Have you verified fuel pressure with a gauge at the regulator or fuel rail with vacuum line unplugged?

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Originally Posted by 2xLS1

What fuel is in it? Closed loop commanded a/f indicates something around 58% ethanol per the stoich a/f table. Have you verified fuel pressure with a gauge at the regulator or fuel rail with vacuum line unplugged?

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Currently, the fuel is mostly e85 and you're right on. The scanner reads 58% ethanol.

I have a fuel pressure sensor logging fuel pressure through the oil pressure circuit and it reads 58 psi with the vacuuum line disconnected. Also, i verified the fuel pressure at the regulator with a mechanical gauge yesterday.

Mostly E85. What does that mean. I would try and get a better handle on the exact alcohol content that is in the tank and compare that to what the alcohol sensor is reporting. Or is this a virtual flex fuel system?

Mostly E85 meaning, the last couple of fuel top-offs from near empty have been e85. The ethanol content has never been measured by myself but the newer style sensor installed seems to be reporting reasonably accurate numbers based on what I've been filling the tank with.

The car has actually been running with the current VE table since last fall (without the turbo, but still 3 bar os). I've had many combinations of gasoline and ethanol run on this ve table. The ECM has been adjusting commanded a/f respectively and it runs the same whether I have 58% ethanol or 10% ethanol. That doesn't completely confirm the sensor is accurate, but I'd say its reasonably close.

Your VE values do not typically increase so much when in boost. They generally will stay pretty constant as you go down the column. Is it possible you are losing fuel pressure?

The boost regions of the ve table haven't been tuned but slightly up to 120 kpa. The lightest spring is installed in the wastegate and the highest map read is 123 kpa. The high numbers in the boost regions are just a rich baseline to be tuned from. Right now I'm trying to focus on the low map areas, which seem unusually high compared to a stock ve table.

I verified fuel pressure with a mechanical gauge and it measures consistently with the pressure sensor I have installed and that is being logged. The fuel pressure holds solid and increases accordingly to the map.

Maybe, I have an injector issue. The Idle pulsewidth is around 1.8 msec. Is this normal for id1000 injectors?

Just for reference, on my ls1 (5.7) my sd60's idle around 1.7-1.8 ms. Would think that the larger injectors would be less on a smaller motor. Assuming you're too rich at idle/low speed hence the need for high VE values. Do you have a minimum fuel delivery floor? LS1's have that under the transient fuel tab as minimum injected fuel. Sometimes that locks the pulse widths higher than needed.