Turbine Housings

Select your vehicle to see Turbine Housings that fit

Turbine Housings: match the A/R to the powerband you actually want

Turbine housings are the exhaust-side casing that wraps the turbine wheel and directs spent gas into it. The housing's aspect ratio (A/R) and scroll design set how fast exhaust energy hits the wheel, which is what decides whether a turbo spools early and low or holds its breath and pays off up top. Swapping the housing on a modular turbo lets you retune that behavior without changing the whole unit, and it's the part you replace when you crack a casting, change your target boost curve, or convert to a divided twin-scroll setup. Choosing the right one is mostly about A/R, flange, and outlet style.

What ThreePiece stocks

This category holds 41 turbine housings from four brands. BorgWarner is the deepest with 18 in the range, followed by Garrett and Turbosmart at 11 each, plus one from TiALSport. Prices currently run from $233 to $1,215 for what's in stock right now, not a locked-in quote. That spread covers everything from single housings to full turbine housing kits with wastegate assemblies.

On the BorgWarner side you'll find EFR-series castings like the EFR B2 80mm 1.45 T4 Twin Scroll (H Type) and the EFR B2 74mm .92 T4 Twin Scroll with wastegate assembly. Garrett's G42 range includes the divided T4 / V-band 1.01 A/R kit and the open V-band / V-band 1.15 A/R kit. From Turbosmart there's the T4 Divided 1.15 A/R 80mm and the T4 Divided 80mm 1.28 A/R.

How to choose

Start with your turbo family and wheel size, because the housing has to match the frame it bolts to. From there the trade-offs are:

  • A/R: the smaller numbers here, like Garrett's 1.01 and Turbosmart's 1.15, favor quicker spool; the larger 1.28 and 1.45 castings trade low-end response for more room to breathe at high flow.
  • Divided vs open: twin-scroll and divided housings like the BorgWarner EFR and Garrett divided kit keep exhaust pulses separated for a manifold built to feed them; the open V-band Garrett is the simpler pairing.
  • Flange and outlet: this range is largely T4 inlet with V-band and standard outlets, so confirm your manifold flange and downpipe clamp before you order.
  • Kit vs bare housing: some listings include a wastegate assembly, which changes the price and what else you'll need to buy.

What else you need with it

Plan the exhaust and oil path around the new housing. Look at Adapters and Fittings for flange and oil-line connections, Gasket Kits and Head Gaskets for sealing, and Fuel Pumps if your new boost target outruns your current fueling. Browse the full Engine Components section for the rest of the build.

Fitment and ordering

Listed fitment data isn't attached to these housings, so match by turbo family, wheel size, A/R, and flange rather than by vehicle. If you're unsure which casting suits your setup, call fitment help at 813-535-5801 or reach us through contact us. Every order ships free, and Affirm financing is available at checkout.

Turbine Housings: match the A/R to the powerband you actually want

Turbine housings are the exhaust-side casing that wraps the turbine wheel and directs spent gas into it. The housing's aspect ratio (A/R) and scroll design set how fast exhaust energy hits the wheel, which is what decides whether a turbo spools early and low or holds its breath and pays off up top. Swapping the housing on a modular turbo lets you retune that behavior without changing the whole unit, and it's the part you replace when you crack a casting, change your target boost curve, or convert to a divided twin-scroll setup. Choosing the right one is mostly about A/R, flange, and outlet style.

What ThreePiece stocks

This category holds 41 turbine housings from four brands. BorgWarner is the deepest with 18 in the range, followed by Garrett and Turbosmart at 11 each, plus one from TiALSport. Prices currently run from $233 to $1,215 for what's in stock right now, not a locked-in quote. That spread covers everything from single housings to full turbine housing kits with wastegate assemblies.

On the BorgWarner side you'll find EFR-series castings like the EFR B2 80mm 1.45 T4 Twin Scroll (H Type) and the EFR B2 74mm .92 T4 Twin Scroll with wastegate assembly. Garrett's G42 range includes the divided T4 / V-band 1.01 A/R kit and the open V-band / V-band 1.15 A/R kit. From Turbosmart there's the T4 Divided 1.15 A/R 80mm and the T4 Divided 80mm 1.28 A/R.

How to choose

Start with your turbo family and wheel size, because the housing has to match the frame it bolts to. From there the trade-offs are:

  • A/R: the smaller numbers here, like Garrett's 1.01 and Turbosmart's 1.15, favor quicker spool; the larger 1.28 and 1.45 castings trade low-end response for more room to breathe at high flow.
  • Divided vs open: twin-scroll and divided housings like the BorgWarner EFR and Garrett divided kit keep exhaust pulses separated for a manifold built to feed them; the open V-band Garrett is the simpler pairing.
  • Flange and outlet: this range is largely T4 inlet with V-band and standard outlets, so confirm your manifold flange and downpipe clamp before you order.
  • Kit vs bare housing: some listings include a wastegate assembly, which changes the price and what else you'll need to buy.

What else you need with it

Plan the exhaust and oil path around the new housing. Look at Adapters and Fittings for flange and oil-line connections, Gasket Kits and Head Gaskets for sealing, and Fuel Pumps if your new boost target outruns your current fueling. Browse the full Engine Components section for the rest of the build.

Fitment and ordering

Listed fitment data isn't attached to these housings, so match by turbo family, wheel size, A/R, and flange rather than by vehicle. If you're unsure which casting suits your setup, call fitment help at 813-535-5801 or reach us through contact us. Every order ships free, and Affirm financing is available at checkout.