It's a pre set tune, it's not a full learning unit. You can calibrate the PROM chip, it will come calibrated from Howell for the engine you tell them. It is not a unit for a modified engine. It's for stock. They can be calibrated for a small cam but the TBI computer requires a good vacuum signal to the MAP sensor. They are good units, GM put millions of them out there and they were pretty much trouble free. Very simple EFI system compared to the full MPI stuff. I used one on a Jeep 6 and it was miles ahead of the crap carb that Jeep used in the 80's. Another friend did an IHC 345 conversion and liked it, later went to a wide band Edelbrock unit and doesn't like it. To me it's like the Autolite 2bbl of EFI units.
Cool, I was just wondering how it was tuned. I'm sure it works wonderfully once it is tuned for an engine as its an OEM system. I just didn't know how close the open loop fuel table would be just taking a stab at what the tune should be for a SBF.
69 Mach 1 428 CJ stock rebuild with Mild roller cam, and Long tube headers, 408hp
Modern Upgrades-TKO600, FiTech, A/C, Rostra Cruise Control
37 Ford Coupe- Boss 351, Massflo EFI, T5Z