Engine Management - BlownByTwins

Schematic showing engine speed continuing to rise while measured output torque falls away, the signature of clutch slip inside a ZF 8HP70 during a dyno pull

Where the Stock ZF 8HP70 Gives Up: 901 lb ft, Measured

The ZF 8HP is the default answer for anyone putting an automatic behind a big power engine, and the question that follows it everywhere is the same: how much will…

Chart comparing the true geometric open area of an 82 mm butterfly throttle against a linear table, showing the real curve sitting far below the straight line across the lower range

Engine Management Mk4 Supra Tuning

Throttle Body Effective Flow Area: Building a Correct Area vs Position Table

Open any modern standalone ECU that runs a throttle-based air model and you'll find a table mapping throttle position to flow area. Open a dozen real calibrations and a good…