Lang Racing: Taking SMG Conversions to the Next Level

By Tom Suddard
Oct 1, 2019 | Paid Article, E46 M3, Lang Racing | Posted in Columns | Never miss an article

Paid Article Presented by Lang Racing Development

Great things happen when you put a team of smart people together around a common goal. Case in point: Lang Racing Development, a Southern California race shop that’s made quite a name for itself in the BMW world. Their goal? It’s simple: Be the best. We spoke with Andrew Lang, the shop’s founder, to find out what that means.

Specializing in the Extraordinary

We didn’t expect to hear what he told us. Unlike most businesses, which find one easy, repeatable task, then do it at scale, Lang Racing purposely focuses on a different strategy: Finding things nobody else does, then doing them at the highest level of quality. They skip the boring jobs that scale, and focus on the under-served niches that need an expert’s involvement. Andrew started with a great example: “BMW S55 engines [the powerplant of the current M3/M4] have crank hub issues, and fixing them requires re-drilling the crankshaft while it’s still in the car. Needless to say, it’s a precise, technical, difficult job… so we’ve become very good at it, and are well known in the BMW world for being the go-to shop for preventative maintenance jobs like this.”

Lang Racing is also big on wild E46 M3 builds, and always have somewhere between 3 and 10 cars in progress at the shop. What’s under the hood? Often turbo- or supercharged S54s, which Lang Racing builds in-house. Andrew was quick to mention a lot of development time spent on the later S65 V8s, too. Lang Racing actually started as just an engine builder, and now ships them to customers all over the world.

Also on the menu? We’ll run down the highlights: Custom built carbon-fiber parts, turn-key track cars, in-house cage fabrication, in-house dyno tuning, in-house corner-balancing and more. They also do some trackside support, but note it takes the right kind of customer to build a relationship at that level. Again, this isn’t a mass-production facility–it’s a group focused on being the best.

E46 M3 SMG to Manual Conversions

What’s their latest project? E46 SMG to manual conversions. And before we explain what that means, we need to give a little bit of a history lesson. Starting in 1997 on the E36 M3 sold overseas, BMW offered what they called an SMG (“Sequential Manual Gearbox”) transmission, which literally means It shifted automatically (and faster than a normal manual transmission), but didn’t have a torque converter or the commiserate rubber-band driving feeling common to period automatics. The transmission–and the acronym–were updated for the E46 M3, which could be ordered with either a traditional six-speed manual transmission or a six-speed SMG-II on both sides of the Atlantic.

Sounds great, right? It was, until BMW reliability was factored into the equation. These days, SMG M3s are the red-headed stepchild, and failures are not at all uncommon. Diagnoses can be expensive, while new parts are pricey and used parts are unreliable. These issues, combined with a polarizing driving experience, have teamed up to tank SMG-II car values: Andrew figures the robot-box knocks about $3000 off the value of an E46 M3 when compared to an equivalent car with a manual transmission.

Fortunately, SMG-II cars have a secret: Aside from the robotics that handle the shifting, everything else is more or less the same as a car with a traditional manual transmission. In fact, it’s often cheaper to pay a shop like Lang Racing to convert an SMG-II M3 to shift manually than it is to fix the broken robot parts. Lang Racing didn’t invent this conversion–the internet figured it out years ago–but instead they improved it, and now sell parts à la carte for the rest of us.

Nuts and Bolts

Considering German engineers’ notorious tendency for overengineering, it’s amazing how little was changed to create the SMG; the two transmissions are internally identical.

In fact, the hardest part is machining the bellhousing, which doesn’t feature any shift detents when installed in an SMG car. BMW skipped that step of the machining process, since computers don’t need to feel where the gears are like a human does. Think you can just find a used manual bellhousing and bolt it up? You could, but they’re rarely offered for sale separately, so expect to pay the price and order an entire transmission. Fortunately, Lang Racing has the solution: They do their own in-house machining, and sell ready-to-go conversion bellhousings for $500.

Once the bellhousing is fixed, the rest is fairly smooth sailing: Remove the SMG pump and hydraulics, install a clutch pedal, master cylinder, and slave cylinder, then open up the tunnel and bolt on a normal shifter. Andrew figures the conversion saves about 20-30 pounds. Oh, and while the transmission is out for that bellhousing replacement, you’d be crazy not to upgrade your stock clutch and flywheel–though they’re the same for both transmissions.

Good vs. Great Conversions

It’s at this point–once the hard parts are all installed–that conversions can go one of two ways: Hacked together as quickly as possible to get the car back on the road, or completed with a bunch more labor thrown in to make it as good as possible. We’ll let you guess which direction Lang Racing chose when developing their process.

Their goal is simple: Every car they convert should be undetectable by an untrained eye. In fact, the only real tell will be a few wires that aren’t removed since they’re taped into big factory harnesses. Andrew says they install every single sensor and wire that would be present in a factory six-speed car, then re-code the computer accordingly. That means that unlike some swaps, their cars have working cruise control, parking sensors, reverse lights, gear position indicators, tilting side-view mirrors when reversing and more. Andrew notes that they’re also happy to take on unfinished swaps, or just handle the programming that the average person can’t do at home.

What’s the result? It’s remarkably unremarkable, meaning it drives just like a factory-equipped M3 with a manual transmission. It’s not that expensive, either–figure starting somewhere around $4000 for a turn-key conversion from Lang Racing. Andrew says that cars are shipped from all over the country for the swap, and it’s become one of the shop’s main projects in recent years. Hollywood has even gotten interested, and you’ll see Lang Racing’s swap featured on the TV show Wheeler Dealers.

Lang Racing might not be on a path to building 1,000,000 copies of anything, but they’re definitely on their way to building the best of everything. You can learn more about E46 SMG conversions here, or follow their social media accounts to see the awesome cars rolling through their shop. And next time you need the best of the best, don’t forget to give Lang Racing a call.

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alfadriver MegaDork
10/1/19 1:44 p.m.

Funny timing- a recent Wheeler Dealer did an SMG to manual swap.  Seems like with the exact same shop.  If you have a MT subscription, it's season 21, episode 2.  

Slippery GRM+ Memberand UltraDork
10/1/19 2:01 p.m.

In reply to alfadriver :

Yep, it’s mentioned in the article. 

LangRacing None
10/2/19 5:33 p.m.

The timing was weird. We actually filmed the show way back at the start of the year and we couldn't really talk about it. Then it premiered and we were able to get the Grassroots team to add in the update right on time. It was really fun. We shut the shop down for two days.

alfadriver MegaDork
10/2/19 8:03 p.m.

In reply to LangRacing :

Cool that you are here- and a question for the process- to help speed up the turnover for customers, have you considered doing a core based system- where a customer pays a HUGE amount until they send the core bell housing back?  Seems like the work you do on one of those will always be the same....  So you can send one kit as soon as someone orders it, and then credit them back when the original bell housing is received. 

Very cool kit- keep a great car with a crappy trans on the road.

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