Just so happens to be a naturally aspirated V8 sourced from a Z4 GTE race car.
Meet the BMW i8 GTR, only it wasn't built by BMW. Well, kind of it was. You see, the i8 GTR is the brainchild of Belgian racing team Hamofa Motorsport. In a nutshell, the i8 GTR is an i8 chassis and body with a BMW S65 V8 swapped inside instead of the factory-build hybrid powertrain. This engine is actually derived from the V8 found in the E90 M3 and it packs quite a punch with around 550 hp. This output goes a long way because the car itself weighs just over 2,400 pounds – nearly 1,000 pounds lighter than a factory-built i8 hybrid.
This engine comes straight out of an older Z4 GTE race car and is bolted into place behind the bulkhead that separates powertrain from the driver, according to Motor1. Also take note of the roof scoop that sucks in cool air to help the engine keep a stable temperature.
There's also a massive rear spoiler to help keep the car stable at high speed. Hamofa also did more than just the engine swap. For example, a good chunk of its frame is now tubular and the body even comes apart like it should in any real race car.
In other words, this thing isn't simply a V8-powered i8 without the hybrid system but rather a full blown race car with one hell of an engine and power-to-weight ratio. The i8 GTR has already participated in at least one race, which took place last month at the Circuit Zolder. Unfortunately it didn't finish but like in every great project, time is needed to work out all of the kinks.