Check the engine and year in the product name, or text us a photo of your setup and we'll point you to the right kit.
BMW turbo engines each test a little differently, so every tester here is listed by model, chassis and engine. On the N54 twin turbo (135i, 1M, 335i, 535i, 740i, X6 and Z4) you cap both intake pipes, one tester for each turbo. MMP relocated and stock location inlets each have their own N54 tester. On the N55 (135i, 335i, 435i, 535i, X1, M135i, M235i, M2 and more) and the N20 and N26 2.0T, the end cap bolts straight to the turbo, so you aren't pushing air through the PCV system. There is also a 4" kit for top mount single turbo builds. Pick the listing with your model and chassis code in the name, for example 335i N55 F30 or 335i N54 E90. Start at 5 PSI and work up. Don't go past 20 PSI on the N55 and N20 kits, and on the N54 you may hear O-ring noise from the intake pipe at around 12 PSI, which is not a leak.
