After developing the first turbo manifold design for the Horsepower Freaks 335i single turbo-kit, some changes were necessary to attain proper tuning feedback for their ECU parameters. While making these changes, we promoted a twinscroll version for the next design giving benefits across the board; including the tuning portion being addressed.

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A pair of open atmosphere dumptubes were aligned to the Tial MVS wastegates alongside of the 3″ turbo-back exhaust..

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There really isn’t much room around the exhaust bank of the N54 engine, so this manifold design has completely changed from the original test-piece to implement the divided turbine housing and now Dual Tial wastegates. The new design allows direct control of the front and rear engine “banks” (cylinders 1-3 and cylinders 4-6) for the wastegate/boost controller and equalizes exhaust flow with equal-length runners feeding into the turbocharger.

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335i-Proto-2

The car is now back together for continued development on the computer system for the single turbokit. Visit Horsepower Freaks for your 335i upgrades!

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Written by John Pham — February 18, 2015