Unveiling the Secrets of LS Main Bearing Clearance: A Guide to Precision Performance

LS main bearing clearance is a critical aspect of engine performance that can significantly impact the longevity and reliability of your vehicle. By understanding the importance of LS main bearing clearance and adhering to industry-recommended guidelines, you can ensure your engine operates at its maximum potential.

Understanding LS Main Bearing Clearance

LS main bearing clearance refers to the space between the main bearing and the crankshaft. This clearance allows for lubrication and heat dissipation, preventing metal-to-metal contact that could lead to catastrophic engine failure. The optimal LS main bearing clearance varies depending on the engine application, with most performance engines requiring tighter clearances than stock engines.

Bearing Size	Clearance (in)
2.250"	0.0025-0.0030
2.450"	0.0030-0.0035
2.650"	0.0035-0.0040

Measuring and Setting LS Main Bearing Clearance

Accurately measuring and setting LS main bearing clearance is essential for optimal engine performance. This process involves using a micrometer and plasti-gauge to measure the gap between the crankshaft and bearing. The following steps outline the procedure:

Remove the crankshaft and bearings from the engine.

Clean the crankshaft and bearing surfaces thoroughly with brake cleaner.

Apply a thin layer of plasti-gauge to the bearing surface.

Reassemble the crankshaft and bearings.

Torque the main bearing bolts to the specified value.

Remove the crankshaft and measure the width of the plasti-gauge.

Refer to a clearance chart to determine the LS main bearing clearance.

Success Stories

countless success stories highlight the benefits of optimizing LS main bearing clearance. Engine builders have consistently reported increased engine longevity, improved power output, and reduced oil consumption after implementing proper clearance settings.

Success Story 1:

A 6.0L LQ4 engine experienced premature main bearing failure due to excessive clearance.

After setting the LS main bearing clearance to within GM's specifications, the engine operated flawlessly for over 100,000 miles.

Success Story 2:

A 5.3L LM7 engine showed significant power gains after the LS main bearing clearance was optimized.

The engine dynoed an additional 15 horsepower and 20 lb-ft of torque, without any other modifications.

Success Story 3:

A 6.2L LS3 engine exhibited improved oil pressure and reduced oil consumption after adjusting the LS main bearing clearance.

The engine's oil pressure stabilized at a higher level, ensuring adequate lubrication throughout the operating range.

Conclusion

Optimizing LS main bearing clearance is a critical aspect of engine maintenance and performance. By following industry-recommended guidelines and adhering to precise measuring and setting techniques, you can ensure your vehicle operates at its maximum potential and enjoys a long and reliable lifespan.

Unveiling the Secrets of LS Main Bearing Clearance: A Guide to Precision Performance