LexFather

BMW has retired its classic 3.2 liter inline six-cylinder engine.

The powerplant, known as the S54B32 amongst BMW engineers and automotive purists, powered the last generation Z4 M Roadster and Coupe, the M3 (E46) and a several earlier generation Z3 M Roadster and Coupes too. The 3.2 liter engine distinguished itself as a naturally aspirated straight-six churning out 343 hp - more than 100 hp per liter without any artificial induction. That simplicity and artfulness of engineering made the engine renowned for its steady levels of torque across the rev band.

One should always be weary when an automaker phases-out a classic product and replaces it with the new and unproven. How many times has a manufacturer messed up the process of renewal and actually taken a product line a few steps back? After all, this engine won the International Engine of the Year award upon its introduction in 2001 as well as winning the 3.0 to 4.0 liter category for six consecutive years between 2001 and 2006.

But this is BMW and maybe a little trust is warranted. They don't usually leap blindly into the marketplace with under-developed products, especially engines.

The S54B32 will be replaced in the Z4 by other inline six-bangers, including a 2.5 liter, 201 hp and a twin-turbo 3.0 liter with 302 hp. Let's hope those powerplants come packed with the same kind of supple sizzle.

JessePS

read about this a few days ago

LexFather

RIP to one of the all time greats, its full of character.

Parker Gen

Wow 343HP out of a NA 3200cc? Pretty impressive.

mmarshall

I wouldn't shed too many tears, Mike. I don't know if you have driven a 135i or 335i with the 3.0L twin-turbo mill (I assume that you have) but, if not, trust me....that is one honey of a powerplant.
I have stated a number of times, here on CL (and I still stand by it) that, for non-track use, I'd rather have a 135/335 than an M3.

And not only is the 3.0L twin-turbo's 300 HP rating impressive, but so is the torque. Its 305 ft-lbs eclipses the M3's 295 ft-lbs, though the M3's 414 HP, of course, kicks in at the high end.

IS-SV

Crash safety and related structure and layout has made straight sixes more challenging to engineer into modern cars.

Faymester

Even good things eventually become (in some form) outdated. Hopefully the 'replacement' is up to par.

I8ABMR

I have to admit the new twin turbo motors are freakn torque monsters. I test drove one before I bought the lexus and I was impressed to say the least. I didnt buy it because the size of the car relative to the price. I am very tall and wide

92 SC400

I've driven E46 M3s and a few 335is and you really cant compare the two. Sad to see this engine go. Anyone know what BMW plans on using to power Z4 Ms?

gengar

I'd imagine they'd just toss the N54 in there. They're probably going to sell out on the M5 with the new twin turbo V8, so they might as well just tarnish the rest of the M badge while they're at it.

babyGS3

isnt the current m5 a v10?

according to the press release, the z4 will have two 3.0L engines.. one w/300 hp (optional 7 speed auto) and the other with 255(optional 6 speed auto)...

92 SC400

I think the TTs were for the 555i not the M5. Though I vaguely recall reading somewhere of a F/I engine in the future for the M5; I could be wrong about this though.

So they're getting the N52 and N54; I would think they would have to have something else to use in the Z4 M though unless the plan is offer a regular Z4 with the N52 and the M with the N54...?

Richie

It was a great engine.