Line Boring Service for Subaru EJ Engines

Subaru EJ engines are often perceived as having weak main bearings, leading to oil pressure issues and premature failure of both main and rod bearings. However, the problem typically lies not with the bearings themselves but with the alignment of the main bearing bores in the engine block. In almost every EJ block, the main bearing bore alignment is likely out of spec, which can cause these issues.

To address this, we offer a precision vertical CNC line boring service that ensures the correct alignment and roundness of the main bearing housing. This service is essential to maximize bearing life and maintain optimal oil pressure.

Our Line Boring Process:

1. Material Removal:

   • We begin by carefully removing 0.04-0.08mm of material from each case half. This step is crucial to prepare the surfaces for precise alignment.

2. Bolting Case Halves:

   • The case halves are then bolted together to simulate the assembled state of the engine, ensuring accuracy during the boring process.

3. CNC Loading and Leveling:

   • The engine case is loaded into the CNC machine, where it is leveled to within 5 microns from top to bottom against the CNC spindle axis. This ensures that the boring process is perfectly aligned.

4. Precision Line Boring:

   • Finally, we perform the line boring within a precision of 5 microns, targeting the minimal recommended bore size for optimal bearing crush and alignment.

Why Choose Our Service?

• Improved Bearing Life: Proper alignment and roundness of the main bearing bore prevent premature bearing failure, ensuring your engine performs reliably under high loads.
• Enhanced Oil Pressure: Correcting the bore alignment helps maintain stable oil pressure, critical for engine longevity.
• Precision Engineering: Our process is carried out with extreme precision, ensuring the highest quality results.

This service is a must for anyone looking to build a reliable and high-performance Subaru EJ engine. Contact us to discuss your specific requirements and how our line boring service can benefit your engine build.