Is your engine making 30 horsepower more since you installed that aftermarket management software on it? In this episode of /Drive’s /Engineered, Steve Dinan, the man , will tell you why he thinks that’s bollocks.

Dinan Motorsport is mostly famous for building extremely fast Bimmers and winning races with them. Back in 1982, Dinan started tuning modern engines by hacking into the BMW 325i’s software and changing the code using trial and error with some guys from Silicon Valley.

The aim hasn’t changed since: flattening the torque curve and improving fuel efficiency. Modern turbo engines give you their peak torque in about a 4,000rpm wide window, which is pretty remarkable to start with, but by adjusting the ignition- and cam timing and putting the hardware behind those changes, engine performance and fuel economy can be improved even further.

Dinan says only custom software built from scratch will work in the future and you shouldn’t take engine calibration lightly, but if you must experiment, start by making it the air-fuel mixture too rich, working your way back from there...

Trust nothing but an honest dynomometer.

An earlier version of this article said Steve Dinan is responsible for tuning the Ganassi Ford GT engines; he is actually involved in the business side of things at Ganassi. This article has been updated at Dinan’s request.

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