In the field of automotive performance, a lot of people don’t really talk much about the Cadillac Northstar engine and it has since been overlooked by most. In a recent video by Calvin Nelson, he dives deep into GM’s 4.6-liter dual overhead camshaft engine, tearing it apart and explaining why it might be the hidden gem for your next project car.
The Search For An Affordable Performance V8
Calvin starts by discussing the struggle to find a V8 engine that offers performance while not being too expensive. He expresses his interest in the Ford Coyote engine but notes that most are pretty pricey and generally bring spun bearings with them when purchased on the second-hand market. This brings him to consider the Northstar engine. Even though it’s an engine that is known for its head gasket problems, it also boasts desirable features that are related to performance applications.
Northstar: A Late Bloomer
GM made the Northstar engine from 1993 to 2011. Early versions had some serious head gasket problems — the aluminum block and head bolt threads just didn’t get along. But, General Motors fixed those issues in later versions, making it a much stronger engine. Calvin calls this particular engine, the LH2, the “final symphony” of the Northstar design, because it incorporates all the improvements they made over the years and is the best version of the Northstar ever produced.
Is an LH2 Engine Variant Really a Great Option?
Here are a few points that make The LH2 Northstar engine a great option:
- This specific design which features four valves per cylinder makes it easier for a lot of air in and out. This is great for high-RPM performance.
- Both the LH2’s intake and exhaust camshafts feature variable valve timing, meaning it excels at virtually any engine speed and has a broad powerband.
- The shorter 3.31-inch stroke lends itself to a higher RPM range, making it perfect for performance applications.
- The main girdle included in the design makes the engine block super strong and able to handle a lot of power.
Taking it Apart: Teardown and Analysis
In the video, Calvin tears down the LH2 engine piece by piece, sharing his thoughts along the way.
- Valvetrain: The valvetrain is the same as the Vortec 4200, a popular engine for budget builds. This means finding parts or even swapping components could be easy.
- Cylinder Heads: The heads have potential, but the valves are a bit small and “shrouded,” which can restrict airflow. Some modifications here could unlock more power.
- Connecting Rods: The rods look just as strong as those in the Vortec 4200, an engine known to handle a good amount of power.
- Crankshaft: The crankshaft has a 58-tooth reluctor, which means it works with popular aftermarket engine management systems like the Holley Terminator X. Plus, it’s a high-quality GM crankshaft, so you know it’s built to last.
- Oiling System: The LH2 has a really cool oiling system with an integrated main girdle and unique oil passages.
By the end of the video, Calvin is clearly excited about the LH2. He thinks it has serious potential, especially with a few modifications. Right or wrong, we like seeing people excited about the potential of an engine platform and are excited to see what he does with it going forward.
A Worthy Contender
The Northstar LH2 might have a bad reputation because of its earlier versions, but it could be a great choice for a unique and powerful engine build with the right variant. With its four-valve heads, variable valve time, a short stroke, and strong internals, it has all the right ingredients for performance. And with some tuning and modifications, it could really shine.
This video is definitely worth checking out if you’re interested in learning more about the LH2. It just goes to show that sometimes the best options are the ones nobody expects.
