Connecting rod length divided by stroke - a guide to side-load and rev character.
Connecting rod length is centre-to-centre between the big and small ends, in mm.
Crankshaft stroke in mm.
Rod ratio = rod length / stroke. Higher ratios reduce piston side-load.
The connecting rod length divided by the stroke. A high ratio (over ~1.7) means less piston side-load and dwell at TDC, favouring high revs; a low ratio (under ~1.5) gives more low-end torque feel but more cylinder-wall load.
Most engines fall between 1.5 and 1.8. Around 1.6-1.75 is a common sweet spot. There is no single best value - it is a trade-off tuned to the engine design.
Indirectly - it shapes the torque curve and rev appetite, which a remap then optimises. It mainly matters when choosing pistons and rods for a build.
The desktop Softechpro Solutions software corrects checksums for 260+ ECU families and does DPF/EGR/AdBlue/DTC off, Stage tuning and DTC diagnostics offline.
See pricing — €299 one-time