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Category: Engine Control
If you put a big VAF on a small VAF computer, then be prepared for;
At WOT, it won't be lean because the VAF is already pegged open, and it's running on the tables, not the meter.
At idle, it won't be rich because it is running closed loop using the O2 sensor.
At cruise above the open loop cutoff RPM, which is 3000-3500 depending on year/model, it will go so lean that it drops off the bottom end of the meter. Which will cause high EGT's. Bad news, maybe even broken parts, if you make a long feathered highway pull, up a hill, or at high speeds.
If you're gonna mess with the engine controls, get an O2 meter, and an EGT meter. If you don't want to buy this stuff, then confine your changes to hard parts. You can make them run good by just changing the mechanical pieces.
People have gone low 14s on the small meter. Do you *need* a big one yet?
related info:
All SVOs, and 87-88 Turbo Coupes have the big VAF meter. Both of these combos were intercooled. All other 2.3 turbo calibrations have the small meter.
So.... If you don't have an intercooler, you probably don't use enough air to need a big meter.