Chevrolet LS7 Small Block V-8: A Complete History Of An Iconic Engine

Summary

• LS7 is one of GM’s most powerful naturally aspirated engines, producing 505 hp and 470 lb-ft of torque.
• The LS7 is a special engine, found in the performance-driven C6 Z06 and fifth-gen Z/28 Camaro.
• Despite being discontinued, the LS427/570 crate engine with 570 hp and 540 lb-ft of torque is an impressive upgrade.

The LS7 engine is one of the more widely known engines of this millennium from Chevrolet, perhaps only outdone by the LS9 that powers the C6 ZR1. Given that the LS9 is supercharged from the factory, however, gives the LS7 the distinction of being one of the most powerful naturally aspirated engines General Motors has ever produced. Stemming from the same LS designated family tree that began with the venerable LS1, the LS7 is a big small block V-8, having 7.0 liters or 427 cubic inches of displacement.

This naturally aspirated engine only came in two factory applications, the C6 Z06, and fifth generation Z/28 Camaro. Both performance cars are awesome in their own rights, but are also both very different, despite sharing this LS7 heart. Pick up a used example of either of these two cars, and you’ll have one special ride, a vehicle that is both a looker and a performer. Though both may be street-driven, their engineering stems from track breeding, and true enthusiasts will recognize the value.

In order to give you the most up-to-date and accurate information possible, the data used to compile this article was sourced from various manufacturer websites and other authoritative sources, including Classic.com, Car & Driver, and Road and Track.

A 7.0-Liter Or 427 Cubic-Inch Beast

The LS7 is a pushrod 7.0-liter engine, one with titanium connecting rods and intake valves. It’ll rev to 7,000 rpm, with a 6,300 rpm horsepower peak, and with more than 400 pound-feet of torque available as early as 2,400 rpm. It’s an all-aluminum V-8, with a forged steel crank.

The LS7 Utilizes A Dry-Sump Oil System

Most vehicles use a deep oil pan that rests at the bottom of the engine, but the LS7 has a dry-sump system, one that uses a more shallow pan coupled with an external oil reservoir. Oil capacity is eight quarts, compared to the 5.5 quarts of the standard C6 Corvette. This system allows the Z06 to maintain oil pressure during sustained high-g cornering.

A Lot Of Naturally Aspirated Power

The base C6 has 400 horsepower, but the LS7 provides the Z06 version with 505 horses. Not only that, but it provides 470 pound-feet of torque. As of 2019, years after the C6’s production ceased, the LS7 remained GM’s most powerful naturally aspirated engine installed in a production vehicle.

First Debuted In The C6 Corvette

The C6, or sixth-generation Corvette, lived from 2005-2013. The Z06 equipped with the LS7, came about in 2006 and ran throughout the rest of the model’s production. The C6 Z06 is a special car.

The C6 Z06 Is Well Balanced

The crazy thing about the C6 Z06 is that as an apex ‘vette, it weighed only 3,147 pounds. That’s 141 pounds less than the base car! This is done thanks to an aluminum frame that weighed only 136 pounds, which was not as strong as the steel base model but weighed a third less. A fixed-cast magnesium roof and engine cradle helped the Z06 chassis remain rigid. Carbon-fiber front fenders, liners, and floorboards helped complete the trick.

Aside from what must be a crazy power-to-weight ratio, the C6 Z06 weighed less than the all-aluminum Ferrari F430 and only a pound more than Porsche’s carbon-fiber Carrera GT. Perhaps it goes without saying that the latter are six-figure cars easy, while the Z06 was under $70,000 new. With a six-speed manual only, the Z06 also gets over 25 mpg on the highway.

2006 Chevrolet Corvette Z06 Specs

(Source: Chevrolet)

Given the impressive performance specs for a naturally aspirated production car, the C6 Z06 remains relevant to this day. You’d be hard-pressed then to find a better car for the money, and that remains true even now. Average prices for a C6 Z06 sit at $50,864 according to classic.com.

It’s certainly more attainable than the C6 ZR1, and the C6 Z06 can be driven daily too, but it’s a car that lapped the Nürburgring in 7:43. Heck, you could spend hundreds of thousands more on a Ferrari or Porsche, and not necessarily have a better-performing car.

Also Installed In 2014-2015 Z/28

The Chevrolet Camaro Z/28 returned in a big way, helping bookend a successful run for the reborn muscle car. The slash is significant, as the car harkened back to the 1969 Camaro and the original Z/28. The fifth-generation Camaro, a car that arose from hibernation in 2010 after 2002’s shutdown at the previous gen’s end, actually outsold the Mustang of the time and the current sixth-generation Camaro.

The LS7 Breathes Life Into The Camaro

Originally powered by Chevy’s sole 302 cubic-inch V-8 in 1969, seeing the Z/28 arrive with an engine such as the LS7 was music to our ears. It was definitely a car worthy of the slash, which with years in between of reduced power and no slash in the trim throughout the generations, meant the car was made more worthy of the track again. Coming standard with Recaro racing seats, this was just the beginning of what the Z/28 brought to the table.

2014 Chevrolet Camaro Z/28 Specs

(Source: Chevrolet)

The fifth generation Z/28 was a heavier and bigger car than the C6 Z06, given the fundamental differences between a sports car and a muscle car. Still, as the two Chevy rides have always shared tech, these two had the LS7 in common. Both also only featured a six-speed manual, with the Z/28 offering a Tremec.

This car ran a 7:37.47 Nürburgring lap, besting the C6 Z06, as well as the fifth-generation Camaro ZL1. The latter is blown with a higher power output, but the Z/28 was lighter, thanks to a stripped-out interior. The Z/28 only had one speaker, a basic stereo, reduced sound-deadening materials, with a rear seat delete option, and the A/C was optional as well.

Also, the Z/28 featured a stiffer track suspension and carbon ceramic brakes, giving it superior stopping power, but a harsh ride. Meanwhile, the ZL1 has a magnetic ride suspension. Perhaps the ZL1 is the better daily, and more livable as such, but make no mistake the Z/28 is a pure driver’s car. Average prices for a used Z28 hover at $64,112 according to Classic.com.

LS7 Based Crate Engine Gets A Power Bump

The good news for LS7 fans is that GM produced a crate engine that was LS7-based, but came with a power output increase. You may have noticed that the Z/28 has more torque than the Z06, but horsepower remains unchanged. This is not the case with this new crate engine that GM produced afterward.

The LS427/570 Crate Engine

As the name implies, the LS427/570 being LS7 based, was a 427 cubic-inch engine. It also came with 570 horsepower, and along with that, 540 pound-feet of torque. This is a significant gain over the production LS7s in the Corvette and Camaro, with peak output coming at 6,200 and 4,800 rpm respectively. Notably, this engine uses a wet-sump oil system, ditching the remote oil tank reservoir and the dry-sump setup of the production LS7.

The Complete Line of LS7 Engines Are Discontinued

Unfortunately for LS7 fans, just as the C6 Z06 and fifth-gen Z/28 production has ceased, so has production of the LS427/570 crate engine. There may be examples of the engine left for purchase, but a prospective buyer would need to inquire with their dealer on availability. Other than that, the only options for getting ahold of a used LS7 are to find the C6 Z06 or the final iteration of the Z/28.

LS7 Swaps & Things To Know

Like many or all LS-based engines, the LS7 may be a popular choice as a swap into any car. With the LS7, this could be a difficult install due to the dry-sump oiling system. Along with the power bump, this is probably what led GM to produce the LS427/570 crate engine, as it is cheaper and easier to install.

The LS7 May Have Increased Reliability Issues When Modified

It’s no secret that when you add things like boost to an engine, via superchargers or turbos, for example, other things will require changes. This is because components internal to the engine and other parts of the vehicle will need to be tweaked to handle the power increase. After all, it seems as soon as you change one thing, you often have to change something else to make it work right. The LS7 seems to work best when kept in stock configuration, and not revved to the redline, as the max power is available before then.

Take It With A Grain Of Salt When Building

On the flip side, although things generally seem to work best when unmolested from a factory, it doesn’t mean things can’t be modified. Surely, reputable shops are out there with the knowledge and experience to build a badass car using the LS7. One just has to keep in mind what one modification leads to, in terms of further mods, and that there is a greater chance reliability takes a hit.

After all, aftermarket companies are quick to point out performance gains, but shop warranties are of course limited. Still, with production of the LS7 discontinued, this may be mostly a moot point anyhow. Nevertheless, anyone would most likely be happy with a C6 Z06, Z/28, or LS427/570 resto-mod classic, all with an LS7 at heart.