Pin It

How to Build a Turbo Manifold

Powerfitz | Sep 11, 2009 |

0 Comments | Rating: 0

Turbochargers have come to non-turbo cars in a big way. More people are looking to get the benefits of turbo boost and they are looking for the best way to get the job done. What keeps many of these turbo lovers from getting a new turbo installed is the cost of custom turbo manifolds. A custom turbo manifold will push exhaust gases into a turbo compressor wheel to build up turbo boost pressure but the old exhaust headers must be realigned toward the direction of the turbo housing to do this. You can make a custom turbo manifold if you have a little welding skill, creative ambition, and know what parts you need to start with to finish the job right.

Things You Will Need

MIG welder Welding mask Eyewear (protective) Grinder (hand, wheel) Salvaged turbo manifold (check pipe diameter) Header flange (check pipe diameter) Exhaust tubing (check pipe diameter) Mandrel beds (salvaged, new) Clamps (vice grips, c-clamp) Measuring tape Collector Chop saw Marker

Step 1

Measure the distance from the exhaust inlet of the turbo to each exhaust port on the engine. Develop a drawing of the finished custom turbo manifold, including the bends that will be needed to turn the exhaust pipes upward toward the turbo housing to make a custom turbo manifold.

Step 2

Cut an old turbo manifold into pieces. Use an old turbo manifold to create the correct bends in the exhaust pipe or you can have a set of mandrel butt weld bends created for you. This can be done by any exhaust shop with a mandrel bender. Because of the cost of new mandrel bends we have included the salvaged turbo manifold method to help you. Use your drawing to cut pieces of the salvaged manifold off of the salvaged turbo manifold assembly and insert the pieces into your design.

Step 3

Bend new pipes so that they will be positioned with an upward bend toward the exhaust inlet of the turbo or insert salvaged bends in place of new ones. The bends should be far enough away from the side of the motor to help protect other engine parts from becoming over heated. Utilize all of the space provided in the engine compartment to direct each pipe back up toward the turbo housing while keep it away from the engine. Leave enough length on the end of each pipe to be able to cut them back to the right length. All the pipes should come together in a four-leave-clover shape and be able to be welded together to keep them together.

Step 4

Measure the distance from the end of the turbo exhaust inlet to the end of the custom exhaust manifold collector. With the collector secured to the turbo housing via the turbo inlet flange, the space that needs to be filled with exhaust pipes will be shown. You can take measurements that help you start turning the exhaust pipes toward the collector or you can weld the collector to the new exhaust manifold pipes using a piece of metal stock as a temporary connector. The armature will let you to remove the new turbo manifold and collector together so you can fill in the open space with exhaust pipes while maintaining the correct distance and position of the collector from the manifold flange.

Step 5

Spot weld all the pieces of exhaust pipe tubing until you have a complete turbo manifold, including the exhaust collector and exhaust inlet flange of the turbo. All the pipes can be welded completely, sealing off all openings that are visible while the turbo manifold is just spot welded together. Use the Mig welder to fill all the gaps in the new turbo manifold pipes and allow the pipes and welds to cool before proceeding.

Step 6

Grind down all the exposed welds outside the custom turbo manifold tubing and inside the turbo header flange where it is welded inside and out. The welds at the flange are the most important to the custom turbo manifold as they receive the hottest exhaust gases. Use a wheel grinder and a drill bit grinder to get inside the tubes of the turbo header flange. Do not grind until the metal becomes red hot. Keeping your custom turbo manifold at the right temperature may include dunking in water to cool after a long period of grinding on new welds.

Building a turbo manifold takes the knowledge of welding and fabricating to get the best results. Your new custom turbo manifold is only as good as its fit and connecting welds. Practice makes perfect with this project, and expect to learn through trial and error until you get a new turbo manifold completed and ready for installation.

Tips & Warnings

TIPS: Using new butt weld joints is the easiest way to get just the right bend in your new custom turbo manifold. A new custom turbo manifold is only as reliable as the pipes that it was constructed from.

WARNING: Openings can let particles enter the engine or turbo compressor when finished and started. Always cover opening in the exhaust manifold with rags while constructing and installing a new custom turbo manifold to protect internal parts from damage during use.