What makes a muscle car, a muscle car? The engine under the hood! The reason these cars became popular was because of the powerhouse under the hood – the outside looks were just icing on the cake. The most popular Chevelle ever built was a 1970 Chevelle SS LS6 454 – a fire-breathing engine that dominated. It wasn’t the 1965 Chevelle with a straight six. While we might have fond memories of cruising in classics with small engines, what made them popular was cubic displacement. Engine swaps have been happening since the invention of the car.
Swapping certain engines into your classic Chevy can be really easy, or more difficult. For example, swapping a Big-Block into your ’70 Chevelle that has a Small-Block is easy; that was done from the factory and we have all the necessary parts to swap it over. Or maybe you’re swapping a classic SBC or BBC into something completely different.
Swapping in a modern motor, such as an LS, requires a bit more work but is still fairly easy. It’s been done lots of times so there is plenty of support for figuring it out and again, we have parts to help make that swap easy.
No matter if you’re swapping an engine into your classic or swapping your engine into some other car completely, knowing the rough dimensions of the engine can help drastically. This way you can measure and see if it will physically fit before you ever pull out your engine hoist.
Shown here is four different engines, all in a ’67 Camaro. A six-cylinder, Small-Block, Big-Block, and a modern LS engine.
Chevy 350 Dimensions
454 Dimensions
LS1 Dimensions
LS2 Dimensions
LS3 Dimensions
LS7 Dimensions
LS9 Dimensions
5.3 LS Engine Dimensions
LM7 Engine
LM4 Engine
If you noticed that the modern LS and the classic Small-Block are similar in size, you’re right – they are. During the development phase of the LS engine, engineers prioritized its dimensions to ensure compatibility with the previous Gen 2 small block Chevy. They aimed for a compact design, similar to its predecessor, making it a suitable replacement.
Comparing heights, many LS versions align closely with the old models, though some truck variants stand taller. The length typically matches at 30 inches, though some variations come close at 29.50 inches. In terms of width, the LS engine is notably slimmer, approximately two inches narrower than its predecessor. This streamlined design has contributed to the widespread popularity of LS swaps in classic GM vehicles initially powered by a small block Chevy, requiring minimal adjustments beyond engine mounts and adapters.
While the Small-Block, Big-Block, and LS engines are by far some of the most popular engines to swap out there – they aren’t the only ones. Cadillac 500s have found themselves in plenty of vehicles over the years. Or maybe you have an Oldsmobile 330 you want to finally put to use. You don’t have to limit yourself, these engines just typically have less aftermarket support to make them work, but it can be done if you’re handy enough.
If you have any questions regarding swapping engines into your ride, give our friendly techs a call at (203) 235-1200 and hop on SS396.com for all your swap parts!
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