Picture a wealthy and discriminating U.S. car enthusiast’s garage circa 1983. There are a few cars you’d imagine being parked there, maybe a federalized Porsche 930 Turbo or even a more exotic Ferrari 512BBi or Lamborghini Countach at the ready. This wasn’t exactly a great period for U.S. sports car enthusiasts, and all three of those cars were only available as grey market cars. Also not available for general U.S. consumption were most of the BMWs built by European tuning firms such as Alpina and Hartge. That didn’t stop determined buyers from importing and federalizing a variety of these machines anyway.
The Hartge H7S pictured here was one of the examples that was shipped from Germany to the States by an enthusiast of fast European cars. The H7S also happens to be an incredibly rare car. It’s all but impossible to know just how many in particular were made, but the general consensus among those familiar with such minutiae is that there are a mere three of these big, luxury performance sedans still in existence today. Which makes 930 Turbos and 512 Boxers seem downright common by comparison.
The E23 that the Hartge H7S was based on was introduced in 1977 as the replacement for the big E3 sedan, more commonly known as the Bavaria. The E23 was a blocky but four-door that was aimed squarely at executives and business people. With the exception of the South Africa only 745i, which was equipped with the same S38 fitted to the M1 supercar, all E23 used versions BMW’s venerable M30 straight six. From 1982 to 1986 the 735i was powered by a 34030cc, 218-horsepower version of the M30. While not the most popular basis for a tuner car, there were modified versions of the model produced over its production run. The rarity of the model makes more common ‘80s BMWs built by Alpina and the like seem downright common by comparison.
Willie Chin of Boca Raton, Florida is the owner of our featured 1984 H7S. Chin was born in Singapore but moved to New York City in 1983. He spent the next couple of decades traveling back and forth between North America and his native country and also lived abroad in a number of countries. Apparently the U.S. obsession with four-wheeled conveyances rubbed off on him. Over the years Chin has owned a number of German cars, including a 911 SC, a Mercedes 560 SEC and one of his favorite cars, a 1988 535is that he purchased in 1991.
Unfortunately the 535 was sold a few years later when Chin moved overseas once again. He acquired an E39 525i, but the allure of the E28 proved strong enough that he recently began looking for another one. “I like BMWs because they are performance based cars, but they are not too hard-core,” he says. Chin was a frequent visitor to Bring A Trailer, an increasingly essential website that posts interesting cars that are for sale across the U.S. as well as the rest of the world. Like many, Chin would read the daily email that BaT sends out to people on its mailing list. He was in search of another 535is, but an unusual E23 7 Series was delivered to his email inbox one morning. “I said to myself ‘what is that?’” Chin explains. “I knew the 735i, but wasn’t familiar with this model.” Reading further, he discovered that it was one of three Hartge H7Ss purported to exist.
This particular 735i left the factory painted Lapis Blue and fitted with a Getrag 5-speed manual. It also came with a host of options, including power windows, on-board computer, a limited slip differential and anti-lock brakes. Immediately after it left the factory, the BMW was shipped to the Hartge headquarters, where it was turned into an H7S. According to the car’s build sheet, it was equipped with same 245 horsepower Hartge motor that was used in the E28-based H5S. To reach the power figure, the 3.5-liter M30 was rebuilt with Hartge valves and springs and likely received a port and polishing job as well. A higher revving camshaft replaced the stock cam, moving the powerband up the rev-range. A performance computer chip ensured that the fuel and spark settings were recalibrated to compliment the rest of the parts installed. On the exhaust end a Hartge tubular header led into a larger diameter exhaust system.
To ensure that the big Bimmer remained a balanced package to drive, the stock springs were repaced with stiffer, lower springs while the Bilstiens were specially valved for use on the 735i. Larger 16x7 and 16x8-inch Hartge alloys were installed in place of the stock wheels and the exterior of the H7S was modified with a deeper front spoiler and a rear wing mounted on the trunk. And since all examples were based on European versions of the E23, it featured streamlined Euro bumpers instead of the battering ram-like U.S. bumpers and staggered headlights that featured 5-inch inner headlights and larger, 7-inch outer headlights. Hartge’s trademark side stripes completed the visuals. The performance transformation came at a price. The number at the bottom of this particular car’s U.S build sheet comes in at a staggering $75,038.
Chin was suitably intrigued by the car and before long the H7S was on its way to its new home in Florida. While registering and titling the Euro-spec Bimmer would have been a difficult process in many U.S. states, Florida does not have any emissions regulations, so registering it there was a relatively simple process for Chin. “It’s a big, heavy car for that era, but it moves,” he notes.
Despite the fact that the E23 was a large, executive class sedan when new, the ever increasing size of luxury cars makes the H7S appear surprisingly compact by comparison when seen in person. The European bumpers and lowered ride height also shrink the car further down. Inside are standard issue sport seats that you would find in other BMWs from the era. In this case they’re upholstered in attractive Pacific blue leather with comfortable cloth inserts. The similarities to an E28 stretch beyond the seats as well. Basically this feels like a slightly larger, more luxurious version of BMW’s ‘80s sport sedan. There are a few differences of course. The center console is wider, the dash is higher and the on-board computer is mounted to the left of the steering wheel rather than on the roof just in front of the windshield. On this particular car, there is a Hartge four-spoke wheel, just past which are the typically legible white on black gauges. Outward visibility is generous and the E23’s cabin feels remarkably airy. All that’s missing is a brick-sized, vintage cell phone.
A twist of the key brings the tuned M30 to life with a muted burble through the larger diameter exhaust. At slow speeds, the H7S is as easy as a modern 3 Series to drive and again overall feels like a bigger version of the E28. Despite the headers and larger diameter exhaust, the sound is far from obtrusive and even when engine RPMs head towards the top end of the power band the engine notes remains a distant but powerful sounding growl.
When we ramp up the speeds, the big Bimmer remains stable and predictable around corners. With more weight and larger dimensions than the smaller 5 Series, the H7S doesn’t quite have the agility of an E28, but despite noticeable body roll around corners, it more than makes up for any handling deficiencies with plenty of grip. The limited slip differential puts the power down very well, allowing the driver to get on the power sooner as the big sedan accelerates out of corners.
Backing up the confidence inspiring handling is that smooth, revvy M30. The motor makes consistent power throughout the rev-range but its happiest at higher RPMs. Cruising at 80 and 90-mph and even higher on straight sections of road seems to be the natural way to drive it. At speed its quiet and luxurious, but with a subtle performance feel on the road. The H7S feels happiest at these higher speeds and, despite its age, I wouldn’t hesitate to drive it from coast to coast. It may not be one of the most celebrated classic BMWs around and is a mystery to most who see it, but it is certainly a rare and fascinating footnote from the 1980s era of tuner BMWs.