actually, it looks like the TT5.7 locks to 255 when it sees wot.
Features
Chip Features for Version 5.7 for 86/87 Buick and 89 TTA:
-Fuel and timing curves recalibrated for improved driveability, cold starts, idle, faster spool. The intent is to maximize performance while reducing knock.
-User Adjustable features! - requires a scantool
-User adjustable wide open throttle fuel, +/- 20%, also adjust 1st gear WOT fuel independently +/- 20%
-User adjustable wide open throttle timing, +/-9° from default, 2 separate settings for low gear and high gear.
-Open loop idle for smoothness, idle BLM still has learning capability (not locked to 128).
-For alcohol injection, special timing curves to help reduce "transitional" knock.
-Variable timing based on mph and airflow, provides extra timing in the low/mid boost area.
-BLM lock at WOT to improve consistency.
-Shift light capability through the SES light if requested.
-False knock ignore capability for launch, turns off when preset mph is reached if requested.
-Antistall, helps prevent stalling and reversion through the MAF when lifting off throttle after boost, helpful with higher stall converters.
-MAF/LV8 locks on to 255 under wide open throttle conditions for consistency.
-MAF "Dropout" ignore
-Fan is programmed to come on a 166*F unless otherwise specified.
-Torque converter lockup at cruising is programmed for 45mph unless otherwise specified.
Instructions for this chip located here:
http://www.turbotweak.com/turbotweakinstructions57.pdf