Photo shown for illustration; shade and shape may differ slightly.
ARP connecting rod bolt kit Subaru 1.8L, 2.2L SOHC, 2.5L SOHC/DOHC non turbo and 2.0L DOHC Turbo
Warehouse stock
A connecting rod bolt does not fail on one pull, it fails in fatigue, after millions of stretch cycles. ARP rolls the threads after heat treatment, not before, and that is the step that builds fatigue strength in the thread root, where a crack would start.
Specifications
| Application | Subaru 1.8L, 2.2L SOHC, 2.5L SOHC/DOHC non turbo and 2.0L DOHC Turbo |
| Engine code | EJ18/EJ22/EJ25/EJ20 |
| ARP part number | 260-6301 |
| Note from the data sheet | Q |
What changes in the engine
- The rod bolt holds the rod cap against inertia loads that rise with the square of engine speed, so the margin disappears at high rpm
- Threads rolled after heat treatment leave compressive stress in the thread root, which is why they last longer in fatigue than threads rolled before
Fitting
- ARP ask for the stretch method, measured with a stretch gauge, wherever it can be used
- Without a gauge, torque them using ARP assembly lubricant; the figure differs from kit to kit and is on the instruction sheet in the box