GM's LSX Vs. LS7 Engine: What's The Difference?

When it comes to engine swaps, there might not be one that's more popular than the LS swap. This is in large part due to the easy availability of them, but they are also good performers. The LS7 and LSX are two options available for you if you're looking for some of the best performance on the market from these engines.

The LSX engines are built with racing in mind, and the high-powered LSX-454 produces up to 627 hp. Of course, that type of performance doesn't come cheap as it can run you between $15,000 and $17,000. If this was just any other LS engine, you could save some money by going for it. However, the LS7 is an entirely separate beast, and you're paying a premium for the 505 hp motor. This engine costs close to $19,000, and that's in large part due to it being one of the best engines ever made. Both the LX7 and LSX lines are home to powerful engines, but there's more that separates the two.

The LS7 engine powered the Chevy Corvette Z06 from 2006 to 2013, and it's a big part of why the car was such a good performer. Due to its long production run, it's an engine that's easy to track down even if it's not exactly cheap. Throughout its life, it set itself apart from its LS counterparts, and it was even used in a helicopter at one point. In 2020, an update to it was made that gave it increased performance, including a rise to 570 hp, but it was only available as a crate engine.

This powerful engine was able to go from zero to 60 in 3.6 seconds, so there aren't any secrets about its performance — although the LT6 engine powering the modern and expensive Corvette Z06 can go zero to 60 in 2.6 seconds. If you're looking for something that can push your vehicle to its limits while also having quite a bit of money to spend, there aren't many better picks than this. It was discontinued by Chevy in 2022, but it'll be quite a while before we see it disappear for good.

While the LS7 might be considered the cream of the crop when it comes to LS engines and most popular, the LSX is no slouch at all and has more power. There are three LSX engines available — the 376-B15, 376-B8, and 454. The 454 is the strongest of the bunch, but the 376-B15 and B8 boast 473 and 476 hp respectively. At stock settings, the 454 is at the top with 627 hp, so performance seekers will gravitate toward that as it clears the LS7 too. The LSX-454 is one of the biggest Chevy engines and it's priced as such.

If you're looking for even more horsepower, the bigger LSX-454R engine produces 770 hp. If you thought the $15,000 engine price tag was bad, the 454-R can run you north of $20,000 if you manage to track one down. The list price is $24,037, but you'll typically find them cheaper than that. Nevertheless, that type of pricing keeps this as an enthusiast engine and not much more than that.

At the end of the day, these are both expensive engines that are financially out of reach for a lot of people. If you do have the cash to pick one up, the LSX is certainly the more expensive of the two if you opt for the 454R variation, but you're getting a lot of performance no matter what direction you go in. It's just not going to be cheap no matter what one you decide on.

The LS family of engines is a durable one that will last you for years in stock form. The LS9, albeit the LS9.R variant, is one of the most reliable GM engines ever made, but you won't have much to worry about if you pick up something from the LS line. It'll ultimately come down to what you're looking to get out of your vehicle. If you want the most speed and performance you can find, you'll have to pay for it. If you want something a little more obtainable, the LS7 is a better pick of the two.