A combustion engine makes power by compressing fuel and air in a cylinder, then igniting it. The tighter you compress the mixture, the more power you make. That’s the compression ratio in a nutshell. Most engines have a compression ratio of less than 10:1.
The engine in this Lada has a 22:1 compression ratio. The crazy crew from Garaga 54 wanted “free horsepower” so they tore apart a Lada four-cylinder engine and increased the compression ratio.
Bumping up compression is actually fairly common in the aftermarket world, but it’s usually done by changing heads and installing stronger pistons. Additionally, resurfacing heads can also increase the compression ratio slightly, simply because the resurfaced head is ever-so-slightly narrower, thus shrinking the combustion chamber. These changes usually require stronger parts elsewhere, such as connecting rods, bearings, and so forth.
Garage 54 just decked the head and welded a bunch of aluminum to the tops of the pistons. Seems legit.
They did at least measure the volume of the cylinders and created a mold of the combustion chamber. That allowed the team to do some rough calculations on the compression ratio, which came out to approximately 22:1. Using the mold as a guide, they welded aluminum to the tops of the pistons, leaving very little room for combustion to take place. And in a surprising turn of events, they erred on the side of caution and added a second head gasket, effectively dropping the ratio to around 16:1. A compression check on the cylinders confirmed that the pressure was indeed way up.
Surprisingly, the engine starts up, and with high-octane fuel in a special tank, it even runs pretty well. In fact, the little Lada spins its tires on the full-throttle test run, but that’s when things like engine balancing, preignition, and detonation come into play. There may have been “free horsepower” for a few seconds, but the resulting carnage after shifting into second isn’t far removed from an I Do Cars engine teardown.
Will the team try again for an ultra-high-compression Lada? Based on what we’ve seen from Garage 54 over the last several years, it’s not a question of if, but when.
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