Twin Turbo Size Calculator

For those who love fast cars, knowing how to size twin turbos is key. Garrett Performance Turbos leads in the field with over 35 turbo options. Finding the right twin turbo setup can be tough, but learning about turbo sizing helps a lot. It’s the secret to getting the most power and efficiency from your engine.

It’s important to match turbos right to avoid turbo lag or speeding them up too much. This could hurt your engine. The size of the compressor and turbine wheels, along with the housing, affects how well a twin turbo works. For high altitudes, using 62/62 or 67/73 turbos is best. Some say 62-sized turbos work great for up to 800whp, but bigger ones might not be needed. A LS1 engine hit 870whp with twin 67 turbos, showing what’s possible with the right choice. Turbos like VS racing 62’s, T4, billet wheel, and GT3582’s are popular in the twin turbo world. Smaller turbos are great for quick boost and better response, especially for engines like the LS1.

Key Takeaways

Proper turbo matching is crucial to avoid issues like turbo lag or over-speeding the turbo, which can potentially lead to engine damage.
Compressor wheel size, turbine wheel size, and turbo housing size are all critical factors in determining the overall performance characteristics of a twin turbo setup.
For optimal performance at high altitudes, a twin turbo setup with 62/62 or 67/73 turbos is recommended.
62-sized turbos are suitable for power levels around 800whp, while larger sizes might be unnecessary.
Smaller turbos can provide instant boost and responsiveness, especially for engines like the LS1 that benefit from bottom-end and mid-range performance.

Calculating Turbo Size for Your Engine

Finding the right turbo size is key for your engine’s best performance. Start by figuring out your target crank horsepower, considering drivetrain loss. Garrett has over 35 turbochargers for engines from 0.4L to 12.0L, supporting up to 3000 crank horsepower.

Engine Displacement and Horsepower Targets

Drivetrain loss depends on the transmission type, often higher in automatics. Front Wheel Drive loses 10%, Rear-Wheel Drive 15%, and All-Wheel Drive 20%. For a 600 wheel horsepower goal in a rear-wheel drive car, you need 690 crank horsepower to account for the 15% loss.

Drivetrain Loss Calculations

Autocross cars might use smaller turbos for quick boost, while drag cars prefer bigger ones for power. For twin turbo setups, divide your target horsepower and engine size by 2 to find the right turbo. You can choose between standard and reverse rotation turbos for balanced systems.

Choosing the right turbo means finding one that matches your engine’s power and size well. Some turbos, like the GTX3071R Gen II and G Series G25-550, need careful matching for best performance.

“Turbocharging is a popular way to increase power, primarily seen in diesel engines, and in the context of petrol engines, particularly naturally aspirated ones.”

Turbochargers spin a turbine with exhaust gases, bringing in more air for more power. To turbocharge a petrol engine, you’ll need to upgrade parts like pistons and rods. Turbo engines also need better cooling, more fuel, and space in the engine bay.

When picking a turbo size, think about your engine size, mods, power goals, and how you’ll use your vehicle. Turbo sizes are based on the compressor’s diameter, usually in millimeters. For a 2700cc engine aiming for 400 horsepower, a 48mm turbo is a good choice. The 5.9 Cummins engine might use a 56mm compressor.

Don’t mix turbocharging and supercharging as it can lead to inefficiencies and mechanical issues.

Single Turbo vs. Twin Turbo Setup

Both single turbo and twin turbo setups have their own benefits. The choice between them depends on the engine, power needs, space, and how the vehicle will be used.

Advantages of Single Turbo Setups

Single turbo setups are simpler and cheaper than twin turbos. They also need less space under the hood, which is great for some cars. Plus, single turbos give a wider power range than twin turbos. This is why they’re often used in drag racing, where lots of power is key.

Advantages of Twin Turbo Setups

Twin turbo setups improve how fast and smooth the power comes on. This is because each turbo is smaller, so they spin up faster than a big single turbo. They look great under the hood, making them a hit for show cars. Also, twin turbos are better for city driving, cutting down on lag and making the car quicker.

Choosing between a single or twin turbo setup depends on what you need and want from your project. Things like cost, power goals, space, and how you’ll use the car are key in picking the best option.

Sizing Twin Turbos for LS Engines

Choosing a twin turbo setup for an LS engine means deciding on the right size. You divide the horsepower and engine size by 2 to find the best turbo size. For instance, a 4-liter LS engine aiming for 690 horsepower needs two 2-liter, 345 horsepower turbos. Garrett’s GTX3582R Gen II and G25-550 turbos are great for twin turbo LS setups.

Turbo Size Recommendations

Engines like the 4.8, 5.3, and 6.0 in LS trucks are hard to beat in power. Even the 4.8 or 5.3 Vortec engines can match the power of a turbo 6.0 LS engine with more boost. Twin turbo setups give more power and a smoother power curve. A twin turbo 5.3L can hit over 1,000HP, now tuned to about 750HP.

For LS engines, good turbo sizes are the 7875 Billet Turbo for 4.8 and 5.3 LS builds, aiming for 900-wheel horsepower. For twin turbo setups, consider 6762s or twin 6673 turbos for up to 1,200whp. Think about the vehicle’s weight, use, turbo efficiency, turbine size, and compressor map when picking the right turbo for your LS engine.

Single turbo setups are cheaper and easier to install than twin turbo setups, needing less modification and being less expensive. But, the type of fuel, water/methanol injection, intercooler efficiency, turbo size, and wastegate setup affect how much boost a stock LS engine can handle.

“A twin turbo 5.3L making over 1,000HP with 66mm turbos and currently detuned to around 750HP shows what these engines can do.”

In summary, when picking twin turbos for LS engines, think about the horsepower goal, engine size, and the turbos available. Choose ones that offer great performance, reliability, and ease of driving.

Budget-Friendly Turbo Builds

Turbocharging an LS engine doesn’t have to be expensive. You can save money and still get great power gains. By choosing the right parts and installation method, you can make a budget turbo setup that works well.

Cost-Saving Options

Choosing cast turbo compressor wheels can save you money compared to billet ones. Also, journal bearing turbos are cheaper than ball bearing ones. Doing the installation yourself can also cut down on labor costs.

Speedway Motors has LS turbo kits that make building a budget-friendly turbo easier. These kits come with cast compressor wheels, journal bearing turbos, and basic parts. This makes building a cost-effective turbo setup simpler.

When turbocharging your LS engine, focus on what you really need without spending too much. By choosing affordable, reliable parts, you can have fun with a budget turbo build without losing much performance.

Conclusion

Getting the right size for your twin turbo setup is key to top performance. It’s important to know how to match turbos with your engine. This means figuring out your engine’s power goals and choosing between single or twin turbo setups.

Whether you’re aiming for a budget-friendly or high-performance twin turbo LS, finding the right balance is crucial. Twin turbos can pack more power than single ones and cut down on turbo lag, which helps save fuel. They also make your car accelerate faster than engines without turbos.

There are different types of twin turbo systems, like parallel, sequential, and series setups, to fit various needs. Parallel turbos are great for cutting down on turbo lag and are more affordable. Sequential turbos offer more power and quickness but might need more upkeep. Series turbos are all about big power boosts and are often seen in aircraft and high-performance diesel engines.

FAQ

What factors should I consider when selecting the right turbo size for my engine?

Choosing the right turbo size means figuring out your target crank horsepower. This involves looking at drivetrain loss, depending on your car’s setup (FWD, RWD, AWD). Knowing this helps pick a turbo that boosts performance without causing turbo lag or speeding issues.

What are the pros and cons of a single turbo setup versus a twin turbo setup?

Single turbo setups are simpler and cheaper. Twin turbo setups improve response and power delivery but are more complex and costly. Your choice depends on engine space, budget, and how you plan to use your vehicle.

How do I properly size twin turbos for an LS engine?

For twin turbos on an LS engine, split your target horsepower and engine size by 2 to find the right size. For instance, a 4-liter LS engine aiming for 690 crank horsepower needs two 2-liter, 345 horsepower turbos.

What are some cost-saving options when building a budget-friendly turbo setup?

To save money, use cast turbo compressor wheels instead of billet ones. Choose journal bearing turbos over ball bearing ones. Doing the installation yourself can also cut costs. Speedway Motors offers LS turbo kits that make it easier and more affordable for a single turbo setup.

Source Links

https://ls1tech.com/forums/forced-induction/1909522-twin-turbo-size-62-62-67-73-a.html – Twin turbo size 62/62 or a 67/73 – LS1TECH – Camaro and Firebird Forum Discussion
https://www.garrettmotion.com/news/newsroom/article/how-to-select-a-turbo-with-over-35-garrett-turbos-to-choose-from/ – How To Select A Turbo Part 1
https://www.omnicalculator.com/everyday-life/turbo-size – Turbo Size Calculator
https://dieselcomponentsinc.com/single-turbos-vs-twin-turbos-what-is-best-for-me-turbo-kits-parts/ – Single Turbo & Twin Turbo : Differences & Advantages
https://discourse.automationgame.com/t/single-turbos-better-than-twin-turbos/20154 – Single Turbos better than Twin Turbos?
https://www.americanmuscle.com/single-turbo-vs-double-turbo.html – Single Turbo vs. Twin Turbo: What is Best for Me?
https://www.speedwaymotors.com/the-toolbox/ls-turbo-setups-twin-vs-single-with-sizing-guide/120172 – LS Turbo Setups: Twin vs Single (with Sizing Guide)
https://www.garrettmotion.com/news/newsroom/article/single-vs-twin-turbo-ls-test-jonathan-hurst-gtx4202r-vs-gtx3582r-gen-ii/ – Single OR Twin Turbo LS
https://www.corvetteforum.com/how-tos/slideshows/sizing-turbos-for-an-ls-build-555545 – Sizing Turbos for an LS Build
https://www.460ford.com/threads/budget-twin-turbo-460-build.202025/ – Budget twin turbo 460 build
https://goldfarbinc.com/blogs/news/what-is-twin-turbo – What Is Twin Turbo?
https://en.wikipedia.org/wiki/Twin-turbo – Twin-turbo