Are you partial to Chevrolet’s big-block, small-block, or LS engine?

Before Chevrolet introduced their LS engine in the 1997 Corvette, the debate about power with Chevy guys revolved around the virtues of the big-block vs. the small-block – and vice versa. It’s a battle that will likely never draw a conclusion, but opinions do vary. Let’s take a look at a scenario where an equally-powered big-block and small-block engine are pitted against each other in a shootout – installed in the same vehicle. In this scenario, we’re sure that you have an opinion about the projected outcome.

The 427 cubic-inch big-block is an iconic engine.

The big-block guys will say that the small-block weighs less, and therefore should have an advantage. However, they will also say the big-block delivers more torque, and has the advantage of better head flow, so it can overcome the extra weight disadvantage. The small-block guys will come in and sat that the lighter engine is capable of running higher engine RPM, and that’s where horsepower is made.

But, when trying to keep all things equal, we run into a glitch. Even if we keep the horsepower rating equal – or as close as possible, there are factors that come into play that you might not have considered. So let’s add this caveat, keep the engine displacement equal, we’ll say 427 cubic-inches.

Even the small-block can be made into a 427 cubic-inch powerhouse.

In theory, if you use the same car for testing and changed nothing else except the engine, one of the engines will ultimately be at a disadvantage. In a drag race scenario, the high-revving small-block could benefit from a steeper rearend gear ratio and a looser converter than the big-block. Although the small-block doesn’t produce as much torque as the big-block, the test engines will gain some equality with the aforementioned drivetrain changes. But, then we are expanding the test, and what does that prove? Anyway, we’re getting off track.

It’s no secret that building a small-block is less expensive than building a big-block—when using equal parts, but let’s add a little something else to the discussion. How does an LS engine fit into the mix? There is no denying the LS engine can deliver great power, and since the introduction of the engine in 1997, the price of rebuildable engines has decreased dramatically, making them a viable option. While some guys do not like installing a late-model engine into their classic, some guys welcome the addition.

The claim of ultimate reliability, fuel injection, and availability of parts from any auto parts store does make it a great option. The LS engine has also seen the availability of a carbureted intakes from many aftermarket companies and this makes it look somewhat traditional, and at home under the hood of a classic. But generally speaking, when looking at the LS engine, there is no denying the futuristic look of the individual coils, the EFI, and the overall design of the engine, but do those items eliminate it as an option?

The LS engine can also be dressed up to look like a traditional small-block. Image courtesy: Holley.

That brings us to this point in our discussion; what parameters are being considered when people decide whether to build a big-block, small-block, or an LS-style engine for their project? That’s where you guys come in. We want to know which engine – given the same displacement (let’s go with 427 cubic-inches), you would choose for your next project, and why? We don’t want to hear you simply say “big-blocks rule!”. We want to know why you choose the engine you feel best suits your application. So let’s hear it, we know you have an opinion.