Bmw E28 S38 Swap
By the Editorial Staff
March 16, 2026
The S38 B38 was BMW's ultimate evolution of their traditional 'big-six' motor. It was the largest stock offering, with the latest head design, and most 'hot rodding' done to it. Our goal, our theory, for this build was to install this motor into an E28 "as BMW would have done it from the factory." What does this mean?
This 1987 BMW 5 Series (E28) race car started life as a E28 520i LUX powered a 2.0 L M20B20 inline-six. It is now powered by a naturally aspirated S38 inline-six making approximately 360 hp (264 kW). Determine if you want to make it look like and E28 M5 with just a 3.6L motor, or make it look like a 3.6L E34 test mule.
The concept behind the 3.8L was to make it look like a BMW or Hartge test mule. A very poor condition, abandoned for multiple years, BMW E28 535is housing not only a legendary S38B35 from an E28 M5/E24 M6, but also some brand new desirable parts and more! As I have (Courtesy of ASBO) a decent 110,000 mile S38B36 ENGINE and most parts from an E34 3.6 M5, I am seriously considering the purchase of a nice, clean, E28 that I could transplant the engine into.
I absolutely love the way my E28 M5 drives with it's 286bhp M88/3 and wonder whether. Speaking of the diff, the easiest setup is to transplant the entire rear subframe from an E28 535. It bolts up and lets you use the much cheaper (and arguably more robust) front.
The E28 (2nd Generation) BMW 5 Series was the one car, more than any other, that established and defined the mid-size sport sedan segment. By its second evolution of the 5 Series, BMW had nailed the recipe of a luxury sedan that was large enough to haul four adults comfortably, while sporty enough to easily out. This is a very close clone of an M5.
In fact, it has the S38 M5 engine as well as a dogleg manual 5-speed transmission, M-Sport seats, sport Bilstein suspension and a complete Euro-spec M5 body kit. The only thing that gives it away is the BMW plaque in the engine bay that says 525iA. The good: The S38 motor feels strong and sounds great.
Bimmerforums is the preferred online BMW Forum and community for BMW owners. At Bimmerforums, you will find technical how. If you plan on swapping in a 5-Series engine from an E34 into your early E28 chassis, our plug and play harness adapters are the easiest way to go.
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