5.7L Chevy LS1 Turbo Kit Guide
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Austin holds a technical writing degree and has 5 years of experience working as a Technical Product Specialist at BMW. He is an avid car enthusiast who is constantly watching F1, consuming automotive content, racing on his simulator, and working on his Toyota’s and BMW’s. Austin’s technical writing skills, extensive automotive knowledge, and hands-on experience make him an excellent resource for our readers.
Outputting between 305 and 350 horsepower in American spec, it is a stretch to call the Chevy 5.7L LS1 V8 a slouch. With that being said, as a Gen III Chevy small-block, the LS1 isn’t exactly the most powerful or modern engine in the Chevy LS catalog. Despite being released 25 years ago, the Chevy LS1 has a massive following. To call it cult-like would be an understatement. While some consider the LS1 to be a primitive engine, with a pushrod valvetrain and a shared rod bearing design with Gen 1 and Gen 2 small-block engines from 1954, the LS1 engine has a massive amount of untapped potential.
With the proper modifications to an LS1, there’s no end in sight in terms of the power that you can make from a turbocharged Chevy 5.7L. Even without extensive supporting modifications, there is a pretty wide margin of power potential that you can squeeze out of a turbocharged LS1. In this guide, we’ll cover the basics of turbocharging a Chevy 5.7L LS1 engine.
Chevy 5.7L LS1 Engine History
As far as impactful engines go, the LS1 is at the top of the pile in terms of paving the way for a new generation of powerful American V8s. By the time the late 1990s rolled around, the Chevy Gen I and Gen II small blocks were approaching 45 years old. It was clearly time for Chevy to sink the R&D money into developing a more modern platform. Unsurprisingly, Chevy named this new generation “Gen III.” The Chevy Gen III small block was a blank sheet design. Meaning that it only borrowed a couple of components from the previous two generations. Ultimately, the Chevy Gen III ensign was entirely unique, while still retaining the 4.400-inch bore spacing that has been a staple in Chevy small block designs since the Gen I.
The 5.7L Chevy LS1 V8 was the first engine in the Gen III small block family, released in 1997. The LS1 was found in the C5 Corvette initially, then used in a number of other Chevy cars including the Pontiac Firebird Formula Trans Am, Camaro Z28, Camaro SS, and Pontiac GTO. One of the most notable features of the LS1 is its aluminum block. While other Gen III Vortec engines utilized a cast iron block, they were only found in Chevy truck applications. Additionally, the LS1 is deep-skirted, has built-in crank and cam sensor mounts, and is a cross-bolted 6-bolt main engine. Additionally, the LS1 block features a structural oil pan which increases chassis rigidity.
The LS1’s rotating assembly is extremely strong due to a durable iron crankshaft and powdered metal connecting rods. They also utilize flat-top alluminum alloy pistons which are not only extremely strong but also lightweight. Lightweight piston construction improves overall throttle responsiveness and efficiency.
Chevy 5.7L V8 Turbocharging Basics
Before jumping headfirst into the world of Chevy LS1 turbochargers, let’s talk a bit about the basics first. The LS1 is a nearly indestructible engine if you know what you’re doing with one. With a turbocharger, it is possible to come close to 650 horsepower mark with minimal work compared to other similar engines. With that being said, it is important to know the limits of factory LS1 internals before cranking up the boost.
5.7L LS1 Engine Limits
As we have already established, the Chevy LS1 is an engine that can withstand power figures far beyond its factory performance. In factory trim, the 5.7L Chevy V8 is rated between 305 and 350 horsepower depending on the application. LS1-powered C5 Corvettes edge out Camaro Z27 and Camaro SS applications marginally in the horsepower department. Regardless, turbocharged LS1s can produce horsepower numbers pushing nearly triple the factory figure. That isn’t to say that a turbocharged LS1 nearing 4-digit horsepower figures doesn’t need a significant amount of attention and additional modifications beforehand, because they certainly do.
Ultimately, a turbocharged Chevy LS1 can reliably run around the 550 horsepower mark with proper fueling and a quality tune. Beyond that figure, you’ll want to start considering stronger internal components. Despite the factory rods and pistons being extremely strong, they are cast aluminum at the end of the day. There are reports of stock LS1 pistons and rods being able to withstand upwards of 700 horsepower, but for reliability’s sake, a set of forged pistons and steel rods are a good idea for high-boost LS1s. We’ll cover LS1 supporting mods in more detail in the sections to come.
Two of the most crucial factors in building a long-lasting boosted LS1 are your tune and fueling. These two factors are even more important when you are nearing the LS1’s internal limits. A safe tune is self-explanatory as far as engine preservation is concerned. A tune that limits detonation and keeps internal temperatures low reduces the chance of internal damage. The same can be said of using E85 instead of pump gas, or installing a meth injection kit.
Chevy LS1 Turbo vs Supercharger
Chances are that if you’ve gotten this far, you’ve done some research on the difference between LS1 turbo kits and LS1 supercharger kits. However, if you haven’t thought about it or are still between the two options, we’ll break down the difference quickly. In all actuality, there are significant pros and cons to both methods of LS1 forced induction.
LS1 Turbochargers
While it is nearly impossible to gain the type of performance that you can get from an LS1 turbocharger, there are also some notable downsides compared to an LS1 supercharger. To start, it is important to note that heavily modified turbocharged LS1s have been known to venture into the 2,000+ horsepower territory, which is far more than what is possible with a traditional PD supercharger. However, it takes a lot more time and money to get to that point.
Ultimately, LS1 turbochargers and superchargers work in very similar ways in terms of compressing air and sending it through the engine. The primary difference is that turbochargers use exhaust gas to spin the impeller. Due to the fact that LS1 turbos rely on exhaust gas to revolve, there can be a significant wait for a turbo to kick in at lower RPMs. This is generally referred to as “turbo lag,” which can be extremely prevalent with large single turbos. That can be mitigated by installing a smaller turbo or even going the route of two small turbos.
Overall, the pros of an LS1 turbocharger include the ability to produce more horsepower than a supercharger (at their limits), more efficient power production, no parasitic power loss, and you don’t have to modify your hood to make an LS1 turbo to fit. Who could forget about that blow-off sound, too?
The primary downsides of an LS1 turbocharger kit are that they are generally more expensive and time-consuming to install, there are a lot of additional components to install, the logistical challenges of installing one in a small engine bay, and turbo lag.
LS1 Superchargers
Perhaps the largest difference between the two is how the additional power is delivered. Generally speaking, an LS1 positive displacement blower will provide more power low in the rev range, as there is no lag in power delivery from a PD supercharger. As positive displacement superchargers revolve, they pump a constant volume of air into the intake manifold regardless of how fast they are revolving. That means that there is always power on tap, regardless of where you are in the rev range.
Some people really love this kind of supercharger, as it allows for a nearly naturally-aspirated experience. With that being said, there is some parasitic power loss from installing an LS1 positive displacement blower, as they are belt driven by the engine itself.
Outside of LS1 positive displacement superchargers, there is another type of LS1 supercharger called a centrifugal supercharger or ProCharger. ProChargers are more similar to a turbocharger than they are to a supercharger. Like an LS1 turbo, an LS1 ProCharger intakes air through a spinning impeller. The air is then compressed and sent through the engine. Like a supercharger, however, the compressed air that a ProCharger delivers retains a constant force due to the fact that they are also belt driven. ProChargers tend to be much more expensive than an LS1 PD supercharger. They are also much noisier.
5.7L Chevy LS1 Turbocharger Supporting Mods & Tuning
While it is possible to run an LS1 turbocharger kit at a low boost level without any supporting modifications other than a tune, pushing a turbocharged LS1 to high horsepower figures will require some additional modifications. In the initial 500-650 horsepower stages, headers and fueling modifications are optional but recommended. For LS1 power levels beyond that, those, and other, reliability and performance-enhancing modifications become necessities.
Supporting Mods
There are certainly some turbocharged LS1 horsepower benchmarks where supporting modifications aren’t necessary. The build quality and materials of the Chevy LS buy you a bit of wiggle room before other supporting modifications are necessary. That usually caps at around 500-600 horsepower. With that being said, supporting modifications for a turbocharged LS1 are never a bad thing. They can only serve to increase the robustness of the already strong LS1 engine and tack on some extra horsepower as well.
Obviously, the supporting mods needed for a turbocharged Chevy 5.7L LS1 engine are entirely dependent on your power goals. In the following sections, we’ll break down the supporting mods needed to handle a turbocharged LS1. We’ll cover a variety of ascending horsepower figures.
500 Horsepower LS1
- Turbocharger Kit: $3,000-$7,000
- Long-tube headers: $700-1,500 (Optional)
The 500-horsepower mark is a comfortable benchmark for a turbocharged LS1 build if reliability is a high priority. In fact, looking at how the LS1 was constructed from the factory, it’s almost like GM expected owners to breach the 500-horsepower barrier, especially with forced induction.
At this horsepower benchmark, aftermarket supporting mods are truly optional. With a 500-horsepower goal, you won’t need to run very much boost. Depending on the LS1 turbocharger/turbochargers that you choose, only 9-12 psi of boost will be required to get you to this baseline level. Factory LS1 internals are more than capable of withstanding the forces that a turbocharger supplies to get there. Of course, a proper LS1 tune is always a necessity regardless of the horsepower figure.
With that being said, long-tube headers might be worth considering once you surpass the 500-wheel-horsepower barrier. While the stock exhaust manifolds flow alright, they lack proper merge collectors and reduce flow as a result. Long-tube headers will play into the strengths of an LS1 turbocharger especially, as long-tube headers will benefit high-rpm performance and increase flow overall.
600 Horsepower LS1
- Modifications listed above
- Forged Rods/Pistons (Recommended)
- ARP Head Studs: $300 (Recommended)
- ARP Main Studs: $227 (Recommended)
- Water/methanol kit: $650-1,000 (Optional)
Once you start to venture beyond the 550 horsepower mark on a turbo LS1 build, most LS enthusiasts claim that the bottom end is on borrowed time. While the LS1 crank is rated for somewhere around 800 horsepower, the cast aluminum pistons and rods are the weak point. There really aren’t many limiting factors at this horsepower range either. For that reason, it is recommended to invest in forged rods and pistons to future-proof your turbo setup. With that being said, there are plenty of turbo LS1 owners pushing the 600 horsepower mark on stock internals. There’s just no guarantee on the reliability front. One way to mitigate that a bit is by installing an LS1 meth injection kit, which will significantly reduce your LS1’s internal temperatures and prevent detonation.
While the rotating assembly itself is able to withstand the pressure, a quality set of head studs and main stud bolts are a good investment to ensure as little movement from the rotating assembly as possible.
Additionally, you’ll need to think about fueling as well. At the 600 horsepower mark, you should upgrade both your fuel pump and injectors. Most LS enthusiasts recommend at least a Walbro 255 fuel pump, which sits on the limits of usable. They also recommend 36 lb injectors, with the most common being FAST 36lb (Part # 303608). If you want some room to expand, Racetronix 42lb injectors can also be used.
800-850+ Horsepower LS1
- Modifications listed above
- Performance Valve Springs: $100
- 1050cc Injectors: $700
- Upgraded Fuel Pump: $500-800
- E85 Flex Fuel Kit: $300
- Forged Pistons / Rods: $1,500-3,000
- High CFM performance heads (Recommended): $1,000-$1,500
The 800-horsepower threshold is the point where some more intensive modifications enter the picture. That is both from strength-enhancing and performance-enhancing standpoints. Closing in on 800hp, most LS1 internals will falter from the stress. While I’m sure that some people have done it, it is a very bad idea to run an 800-horsepower turbo setup on stock internals.
At this point, forged rods and pistons are a necessity. That is if you want to see any kind of longevity from your turbo LS1. While some people spring for a set of off-the-shelf Weisco or Diamond-made forged pistons and rods, it can be difficult to source them for your exact build. Custom pistons might be required to work with your build which can get costly.
In order to truly push massive horsepower numbers, many turbocharged LS1 owners opt to swap in a more aggressive camshaft that is designed to work well with a turbocharger. When swapping in a larger LS1 cam, it is important to consider the supporting mods for that too. Valve springs, for example, will need to be swapped out for high-performance ones to prevent valve float from the high-RPMs. Additionally, factory LS1 exhaust valves should be swapped for ones that can withstand a higher temperature range.
Fueling is another key consideration when venturing into the high-horsepower LS1 realm. In order for your LS1 fuel system to keep up with the demand of the turbocharger, you’ll need bigger injectors and either a larger in-tank fuel pump or pump booster. 42 lb+ LS1 injectors paired with higher octane E85 fuel is a good combination for 850+ horsepower LS1s.
Best 5.7L Chevy LS1 Turbo Kits
Due to the fact that the Chevy LS1 is approaching 25 years old at this point, the availability of LS1 turbo kits is scarce when it comes to brand-new options. For that reason, many people opt to piece together their own custom turbo kit. With that beings said, there are some quality options out there on the second-hand market that can be seen floating around LS1, C5 Corvette, and general Chevy LS forums.
New LS1 twin-turbo kits are far easier to come by than LS1 single-turbo kits. There are still some new twin-turbo LS1 kits floating around as well. We’ll highlight those kits in the section to come. Most of the new LS1 turbo kits do not come with a turbo included. Leaving you to source your own. There are some common turbo flange and turbo compressor wheel sizes as well, which we will also cover when we go over the individual LS1 turbo kits.
Turbocharger kits for the LS1 can range in price anywhere from $4,000-10,000. It ultimately depends on the manufacturer, build quality, included parts, and power potential, and selected turbo/turbos.
1) Huron Speed C5 Corvette Twin Turbo Kit
Price: $4,249
HP Rating: 550-1000+ horsepower
Purchase Here: huronspeed.com
In no-nonsense fashion, we’ll kick off this list with the best LS1 turbo kit on the market. That isn’t necessarily a single person’s subjective opinion either. When it comes to user reviews, there isn’t another LS1 turbo kit out there with the kind of street cred that the Huron Speed LS1 Twin-Turbo kit has. When it comes to LS1 turbo kits, it is largely a personal preference in terms of going with either a single or twin-turbo setup. While large single turbos are often more efficient, twin turbos will save a little more space in the engine bay and either spool marginally faster or at the same speed as a single LS1 turbo. Most of the praise comes from the kit’s high-quality build materials, as well as the upgradability that the kit offers.
While the base Huron LS1 turbo kit doesn’t come with multiple components immediately, you’ll have to make some important decisions on their website while ordering the kit. The Huron LS1 kit can be ordered with a whopping 19 different turbo options. These range from VS Racing 6766 T4 0.81 a/r turbos all the way through to Precision PT6870cea Gen 2 turbos. Pricing on these turbos range from an additional $1,295 to $4,000 in addition to the kit’s $4,249 base price.
In addition to turbo options, Huron also allows you to add an intercooler, wastegates, BOV, a boost/vacuum reference kit, a boost controller, and even a meth injection kit. In terms of new LS1 turbo kits, the Huron has the best customization, hands down. Ultimately, the Huron LS1 twin-turbo kit has been reported to be problem-free in terms of installation and street/track running.
2) PTK GM LS1 Turbo System
Price: $4,199 – $5,999
HP Rating: 550-1,200 horsepower
Purchase Here: w.forcedinductions.com
If you have even ventured into the “Forced Induction” section of any C5 Corvette forum, you have likely seen someone mention the PTK GM LS1 Turbo kit. It makes sense too. The PTK LS1 turbo kit was the standard for LS1 kits for some time after its release. The PTK kit, in its higher trim levels, provides all you need to get going with your LS1 turbo setup. At least as far as turbo hardware is concerned. The kit does not come with a handheld LS1 tuner or other tuning solution, so you’ll have to look into those separately.
In addition to just the 304 stainless steel and coated hot side piping, the PTK LS1 turbo kit comes with a Tial wastegate and BOV, all of the necessary hardware, and silicon hoses. They also give you the option of selecting turbo size and intercooler individually, with turbo options. With that being said, the base turbo kit is only available with an MPT-70 Turbo with .96A/R, not that that won’t be sufficient for most LS1 owners.
At moderate boost levels, PTK LS1 turbo kits have breached the 550 horsepower mark on a completely stock LS1. That is typically the low end of the PTK LS1 kit’s performance with no fueling mods or exhaust modifications. As we mentioned above, it can be somewhat difficult to find a brand-new PTK kit for the LS1. As such, it is more likely that you’ll be able to find one listed on any number of GM forums.
3) Turbonetics T4 Twin-Turbo LS1 Kit
Price: $1,999
HP Rating: 500-1,000+ horsepower
Purchase Here: ebay.com
To round off our list, we’ll recommend a popular budget option. This kit might be good for those that have some LS1 turbo parts laying around already. While Turbonetics is widely known as an “Ebay” turbo kit brand, their LS1 turbo kit is surprisingly well-reviewed. Turbonetics turbos have a pretty good reputation in the LS community.
The Turbonetics T4 Twin-Turbo kit comes with two Turbonetics 68AR turbos that Turbonetics claims are good for 600-700 horsepower a piece. While that isn’t confirmed, this kit can pump out some serious power. One of the main complaints with Turbonetics turbos is their reputation to blow oil seals. It is said to be a “when” and not an “if” kind of problem.
You might be a bit shocked by the price of the Turbonetics LS1 Turbo Kit, especially when compared to the other kits on this list. Well, there is a major reason why the Turbonetics LS1 kit is priced so low. That is because the kit does not come with an intercooler, turbo manifold, manifold flange, downpipe, or intercooler piping. It makes a lot more sense now, doesn’t it? Overall, this kit is best for someone that already has random LS1 turbo kit parts laying around. Alternatively, most of the other parts that the kit is missing can be sourced from other vendors as well.
Chevy LS1 Turbocharger Kit Guide Summary
Of all of the engines that you could pick to turbocharge, a Chevy LS1 is a very good pick. The unparalleled strength, variety of turbocharger options, and supporting aftermarket community make the LS1 a prime candidate for a turbo kit. It is no secret that the LS1 can withstand a ton of horsepower right out of the gate. In fact, there are plenty of 500-600 horsepower turbocharged C5 Corvettes running the streets with very few modifications. Stock high-horsepower LS1 builds are tempting for many. However, it is a better idea to play it safe and pair an LS1 turbo kit with quality supporting mods that will improve reliability and preserve your engine.
Brand-new LS1 turbo kits can be hard to come by. That is because the LS1 is approaching 25 years old at this point. With that being said, there are a few go-to options in the LS1 community. These kits are tried and tested with solid results. Both the Huron Speed C5 Twin-Turbo kit and PTK GM LS1 Single Turbo Kit are solid options that are beloved by the LS1 community. If you can’t find one new, keep checking the forums. One is bound to pop up eventually.
If you enjoyed this article and are looking for more Chevy LS1 content, check out our LS1 Supercharger Guide. As always, safe driving!