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gavinc69 gavinc69 is offline
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Join Date: Jul 2008
Location: Bournemouth UK
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Originally Posted by jpnovak View Post
Gavin, glad it's running. Its always a good feeling. Super happy for you.

Please heed my warnings. Do not turn on EGO control until the car is fully tuned. KEEP IT OFF. The correction algorithms can give you false feedback when you are trying to tune. EGO correction is not a substitute for tuning. Your tuning process will take a lot longer and not be as accurate if you turn these corrections on now.

I am not sure why you were seeing the AFR enrich by reducing the req_fuel. That is a global multiplier. Lower req_fuel is less fuel. higher req_fuel is more fuel.

What was happening is that you were so rich you could not burn all the fuel and you have a false lean condition. Eventually you leaned it out to the point where you were closer to some mixture that would actually ignite.

I suggest you do some more time reading the tuning sections in the manuals before you start changing parameters. I don't want to see you have an issue now that you have reached this milestone.

Looking at your VE tables your low rpm, low MAP bins have very high numbers. This is why the car was so rich. You will likely have to decrease the VE bin values by somewhere around 1.44X (0.69) and get your req_fuel value back up to your starting point of 8.3. What will happen is that you will be pumping a lot of fuel under boost. The max value you can enter on a VE table is 255. I guess you will hit that value and not have enough fuel flowing. So you increase the req_fuel and decrease the VE table by the same amount. This is part of the scaling that needs to be setup for your particular engine.
OK cool, I'll turn EGO off again.

I've just been reading about the VE tables & Req_Fuel and how you can scale them so as you said I'll get adjusting those to allow me to flow as much fuel as possible if needed. Thanks all your info explains a lot
1980 SC Flatnose, Euro 3.0, LW Flywheel, 993 Cams, Port & Polish Heads, RS Cut Valves, MSD 6AL, Blaster Coil, Magnacor Leads, Boxster Brakes, WEVO Mounts, TRG Roll Bars, Rollcage, RSR rear fenders, OE Short Sift, K27 7200 Turbo Conversion, OBX Headers, Tial Wastegate, EFI MicroSquirt v3
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