Excessive Boost Leads to Intensive Engine Damage: A Mitsubishi Lancer Teardown

Boost your engine with a 2014 Mitsubishi Lancer Ralliart’s turbocharged inline-four.

The Mitsubishi 4B1 motor has the potential to provide exceptional performance, making it a favorite among devoted Lancer Evolution fans who admire the dependable 4G63 engine. However, even this powerhouse has its limitations when it comes to handling excessive power. As demonstrated by Eric’s teardown on I Do Cars, pushing a 4B11T (2.0-liter turbocharged inline-four variation) with too much boost can lead to problematic results.

The particular motor in discussion was removed from a 2014 Mitsubishi Lancer Ralliart, producing an approximate output of 237 horsepower from the original factory settings. This is comparatively 50 horsepower lower than its rally-inspired counterpart, the Lancer Evolution X. The power unit was jointly developed by Chrysler and Hyundai under the Global Engine Manufacturing Alliance (GEMA). However, for Mitsubishi models, special attention was given to fine-tune its performance.

TOTAL CARNAGE! Mitsubishi 4B11T Lancer EvoX Turbo Engine Teardown

Immediately, it is evident that the engine exploded, causing damage to a section of the engine block. However, we will address this in more detail at a later point. Initially, Eric removed the HKS spark plugs that had been installed as an aftermarket upgrade; upon inspection, all four appeared to be in good condition. This leads to the conclusion that the previous owner had made modifications to the car, making it more susceptible to failures due to these alterations rather than routine maintenance issues.

Upon inspection of the cylinder head, it was apparent that the majority of components were in good condition. However, there were some indications of wear on the camshafts and journals, which could potentially be remedied. Additionally, a crank on the exhaust manifold hinted at an issue resulting from excessive boost.

Now, we can focus on the most thrilling aspect – the engine block.

As was predicted, the separated piston head within cylinder three was completely absent. The oil pan collected a multitude of fragmented metallic fragments. This malfunction inevitably caused harm to additional elements within the crankshaft assembly, such as the bearings and the very crankshaft itself.

Tinkering with a vehicle can be an exhilarating venture for individuals who love cars, but it does not come without a cost. The level of dependability will inevitably be affected. The extent of this impact varies depending on the modifications made. Neglecting to adequately lubricate the car can also lead to mechanical breakdowns, however, Eric’s examination of the oil filter suggests that this was not the cause of the malfunction.

Although the Lancer series is a thing of the past, the 4B1 engine remains in use for modern vehicles such as the Mitsubishi Eclipse Cross in international markets.