Originally posted on Grassroots Motorsports’ website, be sure to check out their excellent publication.

Written by Scott Lear

From the May 2016 issue

Decades ago, the clever German engineers at BMW discovered a way to get sports car people to fall in love with a fairly upright and boxy sedan: They made it seriously fun. They perfected the formula in the early 1980s with the E30-chassis BMW 3 Series, which married a torquey and willing inline-six engine with rear-wheel drive, a perfect front-to-rear balance, an athletic suspension, handsome styling, everyday utility, and a raft of other adjective/noun pairings, almost all of them good.

The Germans are not afraid to stick with what works, and for several decades the 3 Series has merely evolved, changing in minor ways to suit the times without losing the basic ingredients that make it such a joy on the road. None of us wants to live in a world where BMW gets the 3 Series wrong.

At a certain point in their depreciation curve on the used market, cars like the 3 Series hit a sweet spot where club-level racers start to wonder if they have what it takes to populate a successful racing class on their own. So-called spec racing is popular because it maximizes the competitive aspects and keeps costs down by mandating reasonably priced upgrades and banning pie-in-the-sky spending on go-fast goodies.

Each generation of BMW 3 series sold well when new, so there are plenty of them on today’s used market. Plentiful production numbers also mean that spare parts can be found at junkyards and local auto parts stores with relative ease. These cars have always been a favorite of enthusiasts, so there’s a robust selection of upgrade components from various aftermarket companies, which makes prices competitive. It’s no surprise that each generation of 3 Series has had the opportunity to become the star of its own spec series on the American racing scene.

GRM has covered BMW spec racing since its inception, and we even campaigned our own SpecE30 project car a number of years ago with NASA. SpecE30 has been a huge success, but it’s hard to ignore the feeling that there’s a tectonic shifting of the plates beneath the world of BMW spec racing. Those ’80s-era, E30-chassis BMWs aren’t getting any younger, and as newer 3 Series have depreciated, more BMW spec classes have joined the fold.

Each 3 Series generation has an interior that was appropriate for its time, but a funny thing happens when you tear out all the bits and pieces to transform one of these into a race car: With nothing but a steering wheel, three pedals, a shifter and a race seat, the differences between the E30, E36 and E46 models of BMW’s 3 Series become far less pronounced.

They’re all fantastic track machines, but history tells us that only one of these classes will rise to the top. Will SpecE30 continue its reign despite its age? Can the Spec3 class for the E36-chassis cars find its footing? Is it too soon for Spec E46?

To reacquaint ourselves with what’s out there, we invited representatives from each type of 3 Series spec racer BMW to Summit Point Raceway in West Virginia for a bit of back-to-back investigation. Our hosts for the weekend were American Endurance Racing, and they were more than accommodating during their Friday test-and-tune session before qualifying. In fact, the entire morning was a continuous open-track event that afforded us hassle-free access to the track in a terrific, stress-free format.

AER racers are required to run on today’s crop of super-sticky street tires, and two of our spec racers were wearing non-spec rubber, but we’ve found that they’re not far off from the spec-standard race tires of just a few years ago. Our only regret was that a scheduling conflict that prevented us from participating in AER’s awesome weekend race.


Hitting the track in a SpecE30 is like meeting up with an old high school buddy after a long stretch apart and instantly resuming a comfortable conversational rhythm. It’s the absolute baseline for a racing sedan, with the tall-box advantage of great visibility in all directions thanks to the big windows and upright stance.

Power delivery from the tried-and-true M20-spec straight-six is satisfying and smooth, but far from crazy. It’s not slow, but you’d be hard pressed to declare a SpecE30 “fast” these days. The engine runs out of steam right near redline, and the gearing seems fairly tall with ratios that are widely spaced by modern standards. The linear torque delivery means it’s super-easy to keep slip angles in check through the turns. All SpecE30s run the mandatory, and inexpensive (about $200 shipped), exhaust system from Poore Sports.

In the corners it’s very easy to put a SpecE30 exactly where you want. The rules mandate Bilstein Sport dampers and H&R Race Springs that enhance the car’s athleticism without making it overly stiff. The series also permits 22mm front and 19mm rear antiroll bars of the non-adjustable variety, so body roll is plenty controlled with just 2700 pounds to manage. There’s a playful amount of squirm and slip at the limit, but no surprises.

The SpecE30 is a very mechanical feeling car. Its computerized systems, like the engine management and ABS, are vintage enough that you can almost sense the extra time it takes them to think out their next step. Cars have come a long way since the 1980s, so while the E30 was once the class of the world, the bar edges ever upward.

The brakes on our test car felt a little soft, but the pedal still had enough force to lock up the calipers if needed. The rules dictate OEM-style brake discs and calipers, so pads and fluid are the only avenues to get more bite. The smallish 10.24-inch front discs mean that cooling can be an issue at certain tracks, too. It’s not a dire problem, however, and the rules allow for 3-inch ducts from the openings in the front valence below the bumper.

Thanks to its light weight, excellent dynamics, reliable drivetrain and rugged chassis, the SpecE30 makes a fun race car. Age and abundance make it super affordable, too, with turnkey racers available in the neighborhood of $10K, and plenty of cheaper project cars out there waiting to find a motivated builder to turn them into a track beast. At 30 years and counting, however, how long will it be before this model makes more sense as a vintage racer than a contemporary spec series?

Final thought: There’s no doubt that SpecE30 set the standard for BMW spec racing in our scene, enjoying large fields and great competition for more than a decade. These cars have been carrying the torch for a long time, though, so it seems like a handoff in the coming years is inevitable.



If the SpecE30 is the perfect baseline for this type of racing, then the Spec3 is a baseline with every dial turned up just a tick or two. The slightly more powerful M50B25 inline six has the same sewing machine feel as its predecessor, with willing revs and a wonderfully flat torque curve. The E36 weighs a bit more than the E30, so the power-to-weight ratios are similar (16.07 lbs./hp for the E30, 15.19 lbs./hp for the E36). Our maximum speed into Turn 1 wasn’t dramatically higher in the Spec3, but the handling– bolstered by a set of series-correct R-compound tires– was a definite step up. Current lap records show the Spec3 a few ticks quicker than the SpecE30 around VIR Full, but the E30 still has a slight edge around Summit Point.

Spec3 rules call for a suspension setup with Vorshlag Motorsports camber plates, BMW M3 control arms and bushings, Koni dampers, Vogtland Race Springs and Eibach anti-roll bars. If you feel that mandated parts are a limitation on your creativity, this series might not be for you, but keep in mind that such rules are the heart of spec racing. The fewer choices the competitors have, the fewer money-sapping arms races that develop in the search for parts yielding faster lap times. With everyone on the same page modification- wise, it’s up to the driver to find those extra tenths on track.

To keep costs down, Spec3 organizers decided to stick with a smallish 15×7-inch wheel for the class. This allows racers to run the mandated Toyo Proxes race tires in the readily available and inexpensive 225/50R15 size. The extra 20mm of tread width over the SpecE30 tire gives the car a noticeable bump in grip through the corners, but again, it’s just a few ticks, nothing too dramatic.

Unlike SpecE30, where the brake pad rules are open, all Spec3 cars must run one of two specific compounds of Hawk pads. The discs must also remain stock in size, with 11.26-inchers up front, though fancier rotors with cross-drilling or slots are permitted. The Spec3’s slightly larger rotors do offer a touch more confidence at the end of the straights.

The gear ratios in the Spec3 meant we were able to get out of fourth and into fifth partway down the main straight. Fourth gear ran out of steam just a bit before we wanted it to, but the power drop-off at high revs is as good a shift reminder as any.

Like SpecE30, Spec3 rules permit the factory limited-slip differential. Compliance is tested with a torque wrench and a 30mm socket, and the diff must breakaway at or before 70 lb.-ft. to be ruled legal.

Final thought: Visibility out of the Spec3 is absolutely panoramic, and the confidence gained by superb situational awareness of the car’s surroundings should not be underemphasized. When you can see, you feel more comfortable pushing the limits. This is generally true for sedan racers, but we really noticed it in the E36, even more than in the E30.


Spec E46

What a difference a millennium makes. Going from the E36 to the E46, there’s a much bigger jump in overall performance feel than there was between the E36 and the E30. The E46’s basic platform is a nice evolution of the species, but the 330i’s M54B30 straight-six offers considerably more verve than its ancestors, with smoother revs up high, a tight-ratio gearbox, and much less of the out-of-steam feel the earlier cars displayed at the top of their tach range. The extra half-liter of displacement is part of the improvement, but this 3-liter actually feels like a smaller performance engine thanks to its zippy throttle response and willingness to wind all the way out.

This Spec E46 was expertly prepared by BimmerWorld as a test mule and promotional tool for the series, but it actually started out as a $2500 beat-up 330i. There’s no denying that Spec E46 is currently the more expensive option among the three series, however, with really nice fully prepared cars going in the $30K-$40K range. A capable do-it-yourselfer could probably build a highly competitive car for around $25K, though, and those costs are likely to come down a bit as used 330i models continue to depreciate.

Spec E46 rules mandate the stickier Toyo RR, but this car was equipped with AER-legal street tires for our test weekend; despite the larger 17-inch wheels with wider 255mm tires, we were surprised to find that the controls were all a bit lighter in the E46 than in the older BMWs. Steering, brakes and throttle give their all with less physical input from the driver. The shifter is a big improvement, with snick-snick engagement and rapid throws.

We assumed this car was going to be heavier than the others by at least a couple hundred pounds, but it turns out the Spec E46 actually undercuts the Spec3’s race weight by 20 pounds, and it’s just 150 pounds heavier than the decades-older E30 in race trim. As a result, all the positives from the larger brakes, more powerful engine and wider tires don’t really suffer any mass-related downsides.

The E46’s horsepower advantage was impossible to deny, and it pulled hard out of the corners all the way to the braking zones. The engine sounds pretty racy at full song through the BimmerWorld exhaust system ($900) and Y-pipe ($250), and there was no mistaking the fact that we were passing other cars in the test session much more regularly and with relative ease.

The 330i’s more advanced ABS system and much larger 12.8-inch front discs are ready to cover any overzealous braking attempts. After just a couple of hot laps, this car almost dares you to push your braking zones to the limit.

There’s no denying that Spec E46 is aimed at a higher budget target for the mandatory parts, including a fairly advanced $2650 Motion Control Suspension coil-over system. Expect to spend money on a proper differential, too, as the American-market 330i did not come with a limited-slip diff. The rules allow any performance unit that maintains the factory housing and 3.46:1 gear ratio. The springs are mandatory Hyperco 2.25-in. units ($300 for the set). Bushings can be upgraded, and any standard antiroll bars with non-metallic bushings that use the stock mounting points are allowed.

Rather than using dyno pulls to verify legality, the Spec E46 organizers are taking a more high-tech approach using data acquisition and sealed, reflashed ECUs featuring an Epic Motorsports tune ($599). The plan is still coming together, but expect this series to use post-race data downloads from a (probably) mandatory data acquisition system to see if any cars are generating acceleration, braking, top speed or lateral g load figures outside the norm. As a result there’s not a wealth of dyno information available, but one of the for-sale examples posted 221 wheel horsepower, and another had runs in the 217- 223 whp range.

Final thought: NASA Mid- Atlantic’s lap records show that the Spec E46 is 3.6 seconds quicker than the fastest Spec3 around Summit Point, and a whopping 5 seconds faster around the Virginia International Raceway Full Course. These figures are more impressive considering there haven’t been many Spec E46s on track yet. Performance-wise, this car is a big leap ahead of the other two.


A day spent with three fine track machines is always a joy, but inevitably we came away with some preferences, conclusions and conjectures about the future.

The BMW 3 Series, from any generation and in any state of trim, makes an excellent track machine. Right now, simply based on entries and interest, SpecE30 is the king, but this monarch is aging, and there is no heir apparent. Spec3 and Spec E46 are the most likely candidates to inherit the throne, but which will it be?

That said, hail to the king, baby: SpecE30 is an amazing bang-for- the-buck race series boasting terrific fields from one coast to the other. Drivers like it because the racing is close, the costs are super cheap, and the E30 BMW 325 is a lot of fun at the limit. It makes a ton of sense for a beginning racer, as the car’s limits lie well within the performance envelope of a capable rookie, and there are so many of them out there that finding a rental seat or a used machine is an easy option.

As inevitably happens with a 30-year-old car, however, the well is going to run dry. Certain components are going to become difficult to find on the cheap, and what was once a reasonably powerful platform with good brakes and fine dynamics is starting to lose its edge to the relentless evolution of performance. Racing a SpecE30 isn’t going to be as inexpensive in the future as it was in its heyday, and drivers will find that their lap times can only improve so much with the E30 as a foundation.

The next logical step would be Spec3, but this series has been rolling for a number of years and hasn’t really caught on anywhere. NASA Mid-Atlantic has a handful of racers, but the other regions don’t really have a pack of Spec3s in the mix. The car is totally enjoyable on track, it’s old enough that used platforms are dirt cheap and spare parts abound, but our concern is that it’s just not quick enough compared to the SpecE30 to justify the change. If you’ve got the budget for an E36, but you want to go race where people are racing, it makes more sense to compete in SpecE30.

The older brother’s success might be stunting the growth of the middle child in this case, but that’s what the market has dictated. The durability of the E30 has kept so many of them racing that the window of opportunity for Spec3 will likely have closed by the time E30 ceases to be viable. There’s not that much difference between a 25-year-old race car and a 35-year-old race car, particularly when they offer such a similar driving experience.

The Spec E46 strikes us as the most obvious candidate for a future coup. It costs more now, but it also offers a significantly higher level of performance than Spec E30, Spec3 or even Spec Miata– and there are plenty of folks with money who run those spec series because they’re out there, but who are also keen on going more than just a little faster on track. Like its siblings, the E46 seems to have the kind of built-in durability that has made E30 such a long-lived success. And at full clip, a Spec E46 sails by many more targets on track without being any harder to drive. Speed is seriously addictive.

Time will tell if Spec E46 is the future, or if some as-yet-unrealized series will rise up to snatch the crown once SpecE30 relinquishes it. We don’t expect an overnight shift, but Spec E46 has a lot of buzz and, more important, quite a few cars being built for competition.

The next five years should give us a better picture of the future of BMW spec racing in the country. Fortunately, there are no wrong answers: The racing world is a better place with the BMW 3 Series out in force, regardless of generation.