Exhaust & Turbo Downpipes

What Is a Turbo Downpipe?

A turbo downpipe is the section of pipe that bolts to your turbo's turbine outlet and routes exhaust into the rest of the system. It's the first pipe exhaust gas hits after it spins the turbine, so its design affects how freely your turbo can breathe.

Factory downpipes are often crimped or restrictive so they fit tight engine bays. Aftermarket turbo downpipes typically widen the diameter and use mandrel-bent tubing, which keeps the inside diameter consistent through every bend. Less restriction after the turbine can help your turbo spool faster.

You'll also see non-turbo parts called downpipes. On many classic V8s, it links the exhaust manifold to the rest of the exhaust. Browse all exhaust piping if you're building a complete system. For headers, manifolds, and everything else behind the engine, start at Headers & Exhaust. New to boost? Our cars with turbo guide covers how turbo systems work.

Turbo Downpipes vs Exhaust Manifold Downpipes

The difference is what the pipe bolts to. A turbo downpipe mounts to the turbo's outlet. An exhaust manifold downpipe bolts to the manifold on a naturally aspirated engine and carries exhaust toward the rest of the system.

Pypes Performance Exhaust makes stainless-steel exhaust manifold downpipes for popular classic applications, including:

• 1963-1966 Chevy/GMC trucks with a small-block Chevy
• 1966-1971 Ford Fairlane with a small-block Ford
• 1964-1966 Ford Mustang
• 1968-1972 Oldsmobile 442
• 1967-1981 Corvette C3
• 1973 GTO and 1970-1981 Firebird

Pypes also covers select Pontiac Bonneville, Firebird, and Grand Prix models. For newer trucks, JBA offers downpipes for the 2001-2006 Silverado with the 8.1L.

Before you order, confirm the downpipe flange matches your manifold. If you're replacing cracked or worn exhaust manifolds at the same time, buy them together. Merging two pipes into one? Add exhaust Y-pipes to your list.

Duramax Exhaust Manifolds and Downpipe Support Parts

If you drive a GM 6.6L Duramax, match every part to your engine code first. Diesel exhaust parts change between generations, and a part built for one engine code won't always fit another.

PPE Power offers diesel exhaust manifolds and up-pipes for the LB7 (2001-2004), LLY (2004.5-2005), LLY/LBZ (2006-2007), LMM (2007.5-2010), LML (2011-2016), and L5P (2017+). The LMM kit is a high-flow design, and manifolds come in silver or black finishes.

PPE Power also sells the smaller parts that keep a diesel downpipe setup tight. You'll find replacement driver-side up-pipes, OEM-length up-pipes, and downpipe support brackets for 2001-2016 6.6L Duramax trucks. A worn or missing bracket lets the downpipe move and stress its connections, so it's worth replacing while you're under the truck.

Planning the rest of your diesel exhaust after the downpipe? You can also shop MBRP for diesel exhaust at JEGS.

How to Choose Downpipe Diameter and Material

Start with fitment, then match diameter to the rest of your exhaust. Aftermarket turbo downpipes commonly step up from about 3 inches to 4 inches or more. Your size should still match the turbo outlet and the pipe it feeds.

Measure before you buy. Our guide on how to measure exhaust inlet and outlet diameter walks you through getting accurate numbers, so parts connect without guesswork.

Construction matters as much as size, so check these details on each listing:

• Stainless-steel construction for better corrosion resistance
• Mandrel-bent tubing that holds a consistent inside diameter
• Tubing gauge, which tells you the wall thickness
• Flange style that matches your turbo or manifold

Stainless steel holds up to heat and moisture better than mild steel, so it's a smart pick for a long-term build. If you need to modify routing or fabricate a custom section, shop exhaust tubing bends in matching diameters.

Fitment Checks Before You Order a Downpipe

The right downpipe is the one built for your exact year, model, and engine. A pipe that's close but not correct can hit the frame, transmission, or steering and leave you with leaks.

Run through these checks before you check out. Confirm your model year and engine, including the Duramax engine code on diesel trucks. Check whether the part is sold on its own or as a kit with brackets and hardware. Make sure the inlet and outlet sizes match the parts on either side.

If you're adding a turbo instead of replacing a downpipe, plan the whole system first. Turbo placement drives downpipe routing, so the kit you choose decides which pipe you need. Our Chevy LS turbo kits buying guide helps you compare options before you buy supporting exhaust parts.