How Late Model Engines (LME) Turns OE Heads Into Powerhouses

For most automotive enthusiasts, upgrading their OE factory cylinder heads to be more free-flowing are plenty adequate for their performance needs. Take a potent motor, like the high-revving LT4 from GM. Given the right mods and a select few aftermarket upgrades, its top end comes alive with renewed fortitude.

But to do so, one must relinquish said cylinder heads to a professional for modification. This is why many performance enthusiasts turn to Late Model Engines (LME) for assistance.

Here, decades of combustion engine knowledge and countless hours of R&D time meet. All in the hopes of getting those OE heads to produce as much power as possible and get the most out of a factory casting.

Led by none other than engineering mastermind Casey Snyder, LME’s team of self-proclaimed “cylinder head airflow gurus” have turned the business of modifying OE heads into an art form.

We recently spoke with Collin Thomas from LME to learn how the Houston, Texas-based motor modifier turns the virile LT4 V8 into an even more efficient (and effective) piece of machinery. What we discovered was nothing short of impressive…

Steps in the LME OE Head Upgrade Process

While there are a plethora of sub-tasks encased within each stage of the OE head porting and rebuild process, there are eleven essential stages to LME’s program that every OE cylinder head passes through. 

From the initial cleaning and disassembly of the heads once received at the LME facility to the final cleaning and reassembly. The experts at LME adhere to the processes outlined in this article to ensure that every OE cylinder head receives the same level of treatment as a race-spec cylinder head.

Making the Machining Magic Happen, LME Style…

As for LME’s factory head porting program, machining is one of the many ways the company modifies OE heads. After each head goes through a CNC process, each cylinder head is cut for the optimal valve job and the best valve back cut.

After that, the valve job continues with a hand-blending method. This tedious process remains a mandatory step in each OE head job LME completes. This hand-blending technique guarantees that each valve seats properly into the chamber produced by the CNC machine.