Our test car was bought completely stock with the thought in mind of 335i owners looking to make more power from their N54 engines with an otherwise stock car.  The very first mod that was done on the car was the turbo kit.  Originally a bottom mount kit was designed using a Garrett 67mm GTX4088R turbo.  We were not very happy with the design of the log manifold and how laggy the car felt we were back to the drawing board to see how we can get some torque back into the engine without choking it up on top.  The only way we know to do this is to design a longer runner manifold much like we did with the S54 engine which has been proven to make great numbers and take a beating on very competitive race cars.  But making a part like the S54 top mount race only manifold fit into a street trim 335i is a task on its own.  After we pulled the car in and started tearing into build again we came up with a design very similar to S54 without having to delete or relocate any major components.  We were excited to see this manifold in action on an N54 motor and this time with a much smaller 64mm turbo. 

The car was driven daily for a few months to work out any kinks before hitting the dyno and the only issue we had was a small oil leak that was caused by a loose fitting.  Other than that the car ran flawlessly.  In order to make the type of power this setup is capable of we contacted AD-Engineering who agreed to help tune the car.  A new list of AD-Engineering parts were now being installed which includes their Port Injection kit, dual core 1000hp intercooler, and the oil catch can.  We also ordered a Motiv twin disc clutch to hold the power. 


The end result tuned on C16 by AD-Engineering is 749.8whp@30psi.  At 20psi it puts out 565whp and that’s where it’s ran on pump gas plus meth.


Currently the kit is on the site and can be found here 335i Turbo Kit.  


Written by John Pham — February 23, 2016