2 April 2026 · Mason Sorby
It all began in 2019, when a couple of Porsche enthusiasts set out to modernise their own 911 with EFI.
JSR Engineering was founded by Jannik and René, both with backgrounds in mechanical engineering and manufacturing. United by a deep passion for Porsche and all things mechanical, they maintain several development cars in constant evolution, with at least one always ready for a spirited drive.
The individual throttle body system they built is designed specifically for air-cooled Porsche engines, where airflow efficiency, drivability and repeatable real-world performance matter more than a headline number on a dyno sheet. It targets the kind of car where usability, consistency and performance all have to work together: fast road cars as much as competition-focused builds that demand precise throttle control.
Fast forward to 2025, and JSR's ITB system has found a natural home at Rennen Motorsport in Australia, a workshop where performance parts are judged by use, not theory.
Adopted across Rennen's own air-cooled Porsche builds, the system has been tested and refined in real road, track, and competition environments. This hands-on experience led to the system being offered locally as Rennen ITBs by JSR, a solution backed by engineering design and proven under demanding conditions. Rather than a catalogue product, it reflects a shared, engineering-led approach focused on usable, repeatable Porsche performance.
Rennen Motorsport is JSR's Australian principal for the system, an appointment that also covers JSR's suspension geometry, alignment and handling optimisation work for Porsche, so fitment and specification get worked out together rather than as separate conversations. It's now ready and seeking worldwide distributors with a passion for Porsche performance.
“PERFORMANCE PARTS ARE JUDGED BY USE, NOT THEORY.”
