2024 Chevrolet Corvette C8 Z06

Reading the result

The LT6 is the hardest engine on this page to find power in, and that is what makes the result worth reading. It is a naturally aspirated 5.5-litre flat-plane V8 that revs to 8,600 rpm, and GM did not leave much on the table — there is no boost to turn up and no fuel to add. Everything here came from taking restriction out and then recalibrating around what was left.

The three modifications do one job between them: they let the engine breathe at the top of the range where it makes its power. Larger throttle bodies stop the throttle becoming the restriction as airflow peaks. High-flow catalysts cut exhaust backpressure, which is worked against on every exhaust stroke. The intake feeds the pair. None of that adds energy to the engine — it removes work the engine was doing against itself.

The calibration is what turns that into a number. More airflow arriving means the torque model, throttle mapping, cam phasing and spark tables are all describing an engine that no longer exists, and leaving them alone gives back most of the hardware gain. Fifty-nine horsepower on an engine this tightly developed is a genuine result — around ten per cent, on a car where five per cent is difficult.

This is also one of the platforms that can be tuned without the car ever coming to Corona. The Z06 is reachable over the Tune Delivery Network; the Stingray, confusingly, is not.