Tuning my first supercharged engine, any help appreciated..........

[Chris Murray]

I have 2 5.3l and 1 6.0l truck engines that my customers are wanting to add superchargers to, these will be the first tunes that I have tuned for boost. Any help would be appreciated, as I will be tuning all 3 and I am not finding a lot of information out there on this subject.

[joecar]

Which ECM's will be running these engines...?

[Chris Murray]

E38 on 2 of them and LS1B on the 3rd.

[joecar]

E38: has boost tables, you have to use the correct MAP sensor.

LS1B: have to either scale MAP for boost range (i.e. scale/shift all tables referencing airmass/airflow tables) or use a COS (if OEM OS is not compatible, you have to flash in a compatible OEM OS).

Basically you have to do this (whichever of above methods you use):
- scale injector tables to correctly match injectors, rail pressure, FPR's reference method and MAP scaling;
- set suitably rich/safe PE (maybe set overly rich until MAF and VE are corrected);
- set suitably low/safe spark advance;
- set sanity MAF/MAP/ETC tables to avoid reduced engine power mode from triggering;
- scale and/or correct the MAF table using wideband (disable VE and CL/triming);
- scale and/or correct the VE table (VVE in case of E38/E67) using wideband (disable MAF and CL/triming);
- revisit PE, adjust for best torque and power;
- revisit spark advance, adjust for best torque and power;

are you tuning using engine dyno or chassis dyno...?

you will also have to fine tune driveability on street.

if running auto trans, you will have to address any issues with this (increase shift pressure, decrease shift time, adjust shift torque reduction, correct the engine torque model (E38/E67).

[Chris Murray]

Tuning on the street. How are you disabling VE, MAF, CL/timing?

[joecar]

Disable MAF: cause a MAF DTC to trigger (immediately on engine start), see C2901-3, C6001; in some cases may need to remove MAF.

Disable VE: set dynamic airflow threshold (rpm) to zero (causes MAF to be used exclusively).

Disable CL/triming: disable LTFT and STFT, set CL temperature high, watchout for SOL in LS1B COS.