Testing the 4N Motorsport de stroked N55r26 engine on low boost 17-18psi and low timing in these videos. Now that we’ve gathered data on this engine the next sound clip compilation boost will be turned up to the 25-27psi range!



This has been an absolute blast developing this 2.6L motor. We were stuck for a few months with the mevd17 dme not allowing us to get past 8,000rpm. After working closely with MHD and our tuner we were able to find a solution to this with custom code. The way this engine sounds and pulls is nothing like a normal 3.0L N55. The bottom end changes that we made completely changed the engine’s characteristics and sound. The N55r26 revs out and hits 9K rpm’s freely. This is largely due to the decrease in stroke, longer rods, increased piston dwell time, lower rod angle, and less reciprocating mass. More info will be posted soon on how these changes affected this engine.

We are running this engine with our 4N-EFR8374 GT turbo kit. This is an equal length twin scroll turbo kit that hits full boost at 3,800 rpm’s. Even with the de stroke to 2.6L we are still getting full boost before 4K rpm’s but now have a redline all the way to 9K. The N55r26 9K rpm spec engine provides the rpm and the 4N- EFR tubular turbo kit makes the exhaust note.


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