When Toyota unveiled the fifth-generation Supra most complaints were centered around the fact that it has a BMW engine. Purists consider that a BMW-powered Toyota can't be a true Supra and that's not necessarily related to how much power it delivers. BMW's turbo six-cylinder engine is powerful enough for the Supra at 335 horsepower. The issue, according to the gearhead community, is that it can't match the iconic 2JZ unit in the previous Supra. Well, at least an engine expert claims that the BMW-sourced engine could be better than the 2JZ in terms of aftermarket tuning.

What powers the Toyota Supra?

Many of you already know that the Toyota Supra comes with a choice of two BMW-sourced engines. The base model, which is available in Europe and Japan, features a turbocharged, 2.0-liter four-cylinder engine that generates either 194 horsepower and 236 pound-feet of torque or 255 horsepower and 295 pound-feet of torque, depending on trim and specification. The range-topping engine, which is also the only choice in the U.S., is a twin-turbo, 3.0-liter inline-six that pumps out 335 horsepower and 369 pound-feet of torque.

This six-cylinder engine is part of the B58 family of mills that BMW introduced in 2015. The turbocharged engine powers a wide variety of Bimmers, including cars from the 1 Series to the 8 Series, as well as SUVs like the X3, X4, X5, and X7. It also motivates the Z4 roadster, the Supra's sibling. BMW also borrowed this mill to British carmaker Morgan, which offers it in the Plus Six. Is the inline-six in the Supra the most powerful version of the B58? No, but it's among the most powerful in use as of 2019.

Models featuring the B58 engine

BMW M140i

335 HP

BMW M240i

335 HP

BMW 340i

355 HP

BMW 440i

355 HP

BMW 540i

355 HP

BMW 640i

335 HP

BMW 740i

335 HP

BMW 840i

335 HP

BMW X3 M40i

355 HP

BMW X4 M40i

355 HP

BMW X5 xDrive40i/sDrive40i

335 HP

BMW X7 xDrive40i

335 HP

BMW Z4 M40i

335 HP

Morgan Plus Six

335 HP


How does it compare to the 2JZ-powered Supra?

Well, the new engine is obviously more powerful, because we're comparing it to a mill that was discontinued almost 20 years ago. In its most powerful factory setup, the 2JZ delivered 326 horsepower and 325 pound-feet of torque. That's a nine-horsepower and 44-pound-foot deficit compared to the new Supra, which is quite impressive given the age difference. So why are are die-hard fans complaining? It's mostly about the engine's ability to accept heavy aftermarket tuning.

The 2JZ is famous for being reliable and highly durable, to the point that the block and most of its internals can handle outputs much higher than the stock rating. The fourth-generation Supra and its 2JZ-GTE engines are favorites among tuners who usually take things to the extreme with bigger turbos and enhanced internals. We've seen many old Supras churn out in excess of 700 horsepower at the drag strip and modified coupés with more than 1,000 horses aren't exactly rare either. Some went even further and tweaked the engine to the point where it generates 1,500 horses, if not more.

Sure, things become absurd beyond a certain point, but the big question remains: is BMW's 3.0-liter inline-six tunable to high-performance and drag strip duty specs? Skeptics say no, but a new in-depth engine teardown video from YouTube's PapadakisRacing claims otherwise.

How much can the BMW B58 engine handle?

According to Stephan Papadakis of Papadakis Racing, who recently took delivery of a 2020 Supra for a new project, the BMW-sourced 3.0-liter engine isn't as bland as it may seem. Actually, Papadakis discovered some rather surprising things about the inline-six mill.

Officially rated at 335 horsepower, the engine actually churns out close to 400 horses on the dyno. But it's more capable than that, according to Papadakis, who says that the stock internals are capable of handling as much as 1,000 horsepower. That's because the B58 is a closed-deck engine, which makes it stronger than other designs, and it also includes a robust crankshaft, connecting rods, and pistons capable of handling more powerful without updates.

There is a downside though. Papadakis says that the B58 is very complex. It also has an internal manifold made from plastic with an intercooler built into it, which might not be able to handle high-boost scenarios. This is one component that Papadakis will have to upgrade. The thermostat, the engine timing chain and the cam gears are also located in the back of the engine, which will make maintenance rather difficult, but it all depends on how well the chain holds up once the mill cranks out more oomph.

All told, with minor changes, BMW's engine has what it takes to be a high-performance engine with massive power. The 2JZ in the previous Supra became famous for being robust enough to handle outputs close to or in excess of 1,000 horsepower, but it appears that this inline-six mill could do the same. The cool thing is that we will find out soon enough, as Papadakis is already working to take his Supra to 1,000 horsepower.

Further reading

Read our full driven review on the 2020 Toyota Supra.

Read our full review on the 2020 Toyota Supra.

Read our full review on the 1993-1998 Toyota Supra.

Read our full review on the 2019 BMW Z4.