Just getting into tuning... because I bought a 1980 Sterling Jet boat powered by a twin-turbo LM7 5.3. UPS just delieverd my new MVPI2 Pro+
1st Question: Before I hook up and download the file, what do I for a VIN option? Supposedly the boat was tuned already, but I have no idea whether it was with EFI Live or Hptuners. ECM came from a Gen 3 GM but unknown year or VIN. The VIN in the ECM should be readable correct? Do I use my 2 credits that the MVPI2 came with to unlock THAT SPECIFIC vin? OR should I start from scratch with a different ECM with an untouched factory tune ?
NOW FOR THE GOOD PART!!! This engine has NO OXYGEN sensors for the ECM. Only an INNOVATE Wideband on the Left Bank Turbo outlet only that runs up to the guage/contoller. The passenger side bank isn't being monitored at all. Being somewhat unfamiliar with tuning a Gen 3, my first thought is maybe they tuned it solely using the left bank Wideband o2 feedback. Is that even possible? (I would prefer TWO wideband sensors/controllers) one per bank.
3rd Question: when scanning using a Snap-on Solus edge, Im getting a MAF circuit High code. When I purchased the boat I assumed it was tuned speed density, since there was no MAF to be found. If you tune for speed density, eliminating the MAF, will you still get a MAF Circuit high code?
Yes the boat runs, yes it makes full boost, but it has a few hiccups/stutters here and there... and the AFR on the wideband is 14-15.5:1 at full load at 4400RPM in which the jet pump has loaded the engine and the engine cannot push the jet drive any harder. Which is wayy too lean! Hence the reason for tuning the setup.
Engine specs: unknown year 5.3 with 706 heads, unknown turbo cam, 1 3/4 primary turbo headers to twin 70mm snails, dual wastegates set at 14psi, truck intake, 80lb siemens deka injectors (verified by part number on injectors), Aeromotive A1000 fuel pump with a 13101 bypass regulator.
THANK YOU GUYS FOR ANY AND ALL HELP getting me up and going!