The Tale of Two Killer $2000 BMWs

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story by alan cesar • photos by anthony neste and david s. wallens

Contenders at GRM’s annual $2K Challenge know that if there’s a way to make something fast, someone will likely try it. Whether it’s simply turning up the boost on a turbo Diamond Star, shoehorning a big engine into a tiny MGB, or magically merging a BMW Isetta and a Mazda RX-7, each crazy idea is someone’s potential claim to fame.

BMW’s E30-chassis 3 Series is a staple at the Challenge thanks to its low price and capable suspension, so we’re accustomed to seeing these cars every year. For the Kumho Tires Grassroots Motorsports $2010 Challenge, though, there were two very different box-flared takes on this hunk of 1980s metal.

Snails Taller Than Stonehenge

Carlos Mendez, James Hageman and his Condor Speed Shop team took the modern approach of bolting on the boost and turning it up to 11—and then past 21. The team’s 1988 BMW 325is, dubbed the DirtE30, has been Challenged before, with each successive iteration upping the ante over its predecessor. They started with the car’s stock 2.5-liter inline six and bolted on a turbo manifold from a diesel Bimmer.

They did well with the Volvo turbo they originally strapped to that manifold, but Carlos and James dumped the Swedish snail and tapped the exhaust side of an American truck for a replacement. “We purchased the Holset turbo off of a person who owns a Dodge turbo Cummins diesel truck,” James explains. “We went from running 11 psi with the Volvo turbo to 21 psi with the Holset.”

To keep the big truck turbo from hitting the valve cover, Carlos needed to raise it by 3 inches. A couple of T3 flanges and some scrap square tubing did the job. “Because the Holset was a twin scroll, I kept the exhaust gasses divided in the adapter piece using a steel plate welded inside,” Carlos adds. “That’s why it spools so quickly for such a big turbo.”

The team tried MegaSquirt engine management in the past, but it left them lost somewhere backstage for way too long. After learning that lesson, they chose to stick with their track-tested stock Motronic engine computer, augmented with a chip bought on eBay and bigger fuel injectors from a Jeep Cherokee. The only change to the engine itself was a bit of porting on the intake manifold.

When fully amped, the DTM-themed car blasted a 12.3-second quarter mile—but also blasted through its head gasket after just three runs up the strip.

Smell the Rubber

To keep the car glued down, the team needed some serious wheels to hold their super-wide Hoosier slicks. The box flares they fabricated a couple of years ago offered ample room for a big wheel-and-tire package—they just needed an inexpensive solution.

Enter a set of blemished 15x10-inch Bassett wheels originally intended for stock car racing. Custom adaptors formed from half-inch-thick aluminum mate the Bassett’s wide-five bolt pattern to the stock BMW hubs. The DirtE30 now claims front and rear track widths that are 8 and 9 inches wider than stock, respectively.

The suspension received some updates for 2010, too. Condor Speed Shop pulled their H&R springs—which were supposed to lower the car by 2 inches—in favor of a more customized setup. After the BMW lost a significant amount of weight, those H&R springs no longer provided a lowered ride height. Carlos’s solution was to adapt cheap coil-over sleeves from a Honda Civic and fit them with used racing springs.

“We picked up some 600 lbs./in. and 750 lbs./in. springs on eBay and set them on the rear trailing arms with some plywood spacers,” Carlos explains. “We kept the same Bilstein HD shocks we’ve had since 2007. Together these two things made the biggest improvement to our [autocross] times.”

Several years of Challenges and plenty of autocross testing between events did a number on the car’s original motor mounts. Both of them broke during a test session in January of 2010.

Carlos called in a family favor and had his dad make a pair of solid mounts out of high-strength polyethylene. He didn’t stop there, however. He also upgraded the transmission and rear subframe mounts with custom pieces of the same material to remove slop from the driveline. Carlos now sells these same mounts out of his eBay store,

Going Space Truckin’

Turbocharging isn’t the answer to every problem, however, and we all know the old adage: There’s no replacement for displacement. Terry Fair and his Vorshlag Motorsports team took faith in that mantra and ripped out their BMW’s six-chambered heart for want of something bigger, something with a bit more punch.

Terry toyed with several possible engines to swap into his 1986 325e, factoring each one’s cost, weight, size and transmission options. The shop had a 4.5-liter Nissan engine left over from an abandoned project, so the team mocked it up first. “This four-cam V8 was enormous and would have never fit this chassis without major strut tower and firewall surgery,” Terry explains.

He then came upon a 5.3-liter V8 from a Chevy truck. An iron-block variant of GM’s venerated LS engines, it would be a rock-solid and reliable choice. The Vorshlag team then got to work modifying a pair of exhaust headers to fit within the E30’s chassis. After that, they added power by fitting an intake manifold and camshaft from an LS1-powered Camaro.

The V8’s $500 price tag may seem low if you consider that the engine’s torque plateau is wider than the crowd area at Donington Park, but it’s significant when the total budget for the big show is just $2010. The list of affordable transmissions was narrowed down to a relatively weak T5 found in a V6 Camaro. However, Terry’s team played the right romantic music to get the two to mate. “We used the often-ignored ‘SFI bell housing’ $2K Challenge safety rule to be able to get an engine swap-friendly scatter shield into the budget for zero dollars,” Terry explains. “That saved us a lot of custom work and some budget money.”

To get torque to the ground, Vorshlag cut the rear subframe out of his E30 and fabricated a new one out of 2-inch square tubing. Next he upgraded the differential carrier by replacing the rear cover with one from an E36-chassis BMW, then installed limited-slip internals.

E36, the Number of the Beast

Vorshlag Motorsports’s E30, just like the Condor Speed Shop car, uses every inch of available space under its ample handmade box flares. But what Condor Speed Shop did with incredible wheel offsets, Vorshlag accomplished with incredible wheel offsets and serious suspension swaps.

Many of the components from the BMW E30’s sequel, the E36, are more or less interchangeable. When Terry’s team actually commenced the swapping, however, he discovered that it was like substituting Metallica for Motörhead: Sure, the former played a lot of songs written by the latter, but they’re just not the same band.

The team tried various BMW front lower control arms until he found an arrangement that would make Lemmy proud. However, the strut towers needed significant cutting before it would all work properly. He fitted used Koni struts up front and Bilstein shocks out back, then converted the springs to a coil-over setup with 750 lbs./in. Eibachs. To match the front’s bigger E36 brakes—a full inch larger in diameter—Terry added a pair of rear hubs from a BMW Z3.

An added advantage of this setup was that the BMW now had five-lug wheels on a 120mm pattern. Terry set out looking for 15x10-inch wheels that would fit the budget, and he came upon a set of steel Aero Race wheels with a GM 4.75-inch lug pattern for a mere $50 each. He wagered that at autocross speeds, the difference of less than 1mm from the BMW’s metric spacing was close enough to be safe. He slipped on the same-size Hoosier shoes worn by the DirtE30.

Final Countdown

When these automotive hair-metal heroes finally took to the track, Condor Speed Shop’s several years on the road proved they knew how to ride the tiger. Carlos and James had tweaked the suspension, making adjustments at autocross events between each year’s Challenge. The DirtE30 also had a fully stripped interior, sharper bodywork, and a phenomenal DTM paint job complete with a Warsteiner-inspired Condor Speed Shop logo.

Since the $2010 Challenge, Carlos has prepared a stroker engine and upgraded the inline six’s head gasket to compete in the Ultimate Track Car Challenge. Their DirtE30 is done with low-buck racing, however. “It’s no longer a Challenge car because we’ve exceeded the budget,” Carlos says.

On their first time out, the Vorshlag Motorsports team showed that they could build an impressive car under budget. Their none-more-black approach to a color palette was simple and well executed, but the mechanics still needed some tweaking. At the $2010 Challenge, a broken transmission kept them from laying down a good drag strip time, and a lack of time to fine-tune their suspension hampered their autocross performance.

Terry has since swapped spring rates and changed some settings, and he reports a significant improvement in the car’s handling. “A box of springs and a day of testing would’ve easily gained us six-tenths on the autocross course,” he says.

Though they’re two very different takes on the same underlying hardware, we loved seeing both cars in competition. Keep your electric eye focused on future GRM events to see these Teutonic track rats in action.

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