San Diego Evo's
Food for thought....the stock Evo flash has about 8 counts of knock on 91 oct, just imagine what the knock counts are going to be when you lean out the fuel mixture to the desired 11.2 AFR for peak output (stock is about a 10.0 anything after 5k rpms where is also where the most knock is seen on a stock flash)....
So, with that said....don't wast your money on that SAFC and get flashed.....You got PM...
Last edited by alan678; Apr 10, 2008 at 09:24 AM.
+1 for getting a tune before using the SAFC
the main problem with SAFC controllers is the way they go about making changes to the fueling by modifying the MAP/MAF signal.
on modern cars the MAP/MAF signal is used not only for fueling, but also controlling ignition timing.
so if you want to remove fuel, you essentially "trick" the ECU into thinking the engine is not working as hard & thus you use less fuel, but here is where the problem lies. if you are tricking the ecu into thinking the engine is not working as hard, it will also add ignition timing & like alan said, the OEM tune already has aggressive timing & if you cant add timing, you cant remove fuel :/
one way of using the SAFC is to have your ECU reflashed but use mild ignition timing to give you some working room so you can add/remove fuel with the SAFC before you start getting into knock
the main problem with SAFC controllers is the way they go about making changes to the fueling by modifying the MAP/MAF signal.
on modern cars the MAP/MAF signal is used not only for fueling, but also controlling ignition timing.
so if you want to remove fuel, you essentially "trick" the ECU into thinking the engine is not working as hard & thus you use less fuel, but here is where the problem lies. if you are tricking the ecu into thinking the engine is not working as hard, it will also add ignition timing & like alan said, the OEM tune already has aggressive timing & if you cant add timing, you cant remove fuel :/
one way of using the SAFC is to have your ECU reflashed but use mild ignition timing to give you some working room so you can add/remove fuel with the SAFC before you start getting into knock
And yes, we're due for a BBQ/dyno day
