Eight things you might not know about about the R129 Mercedes SL

The original SL was a bit of a world-beater when it debuted, what with being the fastest road car ever at that point. Being based on a race car meant the handling wasn’t exactly shabby, as evidenced by a win at the 1952 Carrera Panamericana, despite – and we’re not joking – a vulture going through the windscreen at one point.

The Pagoda SL that followed could keep a Ferrari 250 GTO honest around a tight track, and the R107 that followed the Pagoda went rallying with remarkable success.

So it stood to reason that the new SL had to offer up the goods in that regard. Helpfully, a 32-valve, 5.0-litre dual-cam V8 with 322bhp meant it could run the quarter mile in the 14s and do 0-60 in less than six seconds, and even the six-cylinder version was quicker than the previous V8 SL.

And yet, as far as we can tell, Mercedes never took it racing. And that might be down to the next point...

As you likely already know, the SL designation comes from ‘Super Light’, due to the fact that the original 300SL racing car weighed just 870kg. The road car was heavier, of course, but the R129 started making a bit of a mockery of the SL name, especially with the V12s.

Contemporary 0-60 and quarter mile tests of the 500 and 600 SL found that the 600 was no faster than the 5.0-litre V8, despite another litre of displacement and four extra cylinders. That’s likely down to the fact that the V12 model sat on the wrong side of two tonnes, a hefty jump from the already hefty lump that was the (comfortably) 1.8-tonne V8. So, a bit of a Top Gear top tip, then – as desirable as the V12 model might be, you’re really not missing out on anything in the performance stakes by going for the V8s. And neither’s going to be a proper sports car by any stretch of the imagination. Grand tourer, though? Whoo, just try to find one grander.

And this is from the man who designed the Mercedes C111-III concept. Yet it’s the R129 SL, along with the W201 190E (due to how important it was to the company) that gets Bruno Sacco’s vote.

Sacco said that “the R129 just has the perfect profile”, and that it was “the most perfect car of my career".

And it’s not like he’s given to flowery assessments of his own work, either – he bluntly called the W140 S-Class that he designed “four inches too tall”.

Well, like he said, he’s “not a fan of elaborate language”.

The seats alone had 20 patented parts including an inbuilt seatbelt that automatically raised or lowered to match the height of the headrest. They also had magnesium frames and five separate electric motors apiece, and won actual awards for how good they were. How much did you want to be at that awards ceremony?

But back to the SL – It was the first Super Leicht with brake assist, stability control, and active damping, the latter of which was teamed with self levelling suspension. Add in rain-sensing wipers, occupant detection for the passenger seat that disengaged the airbag if the seat was carrying less than 10kg and central locking that worked on the storage cubbies as well as the doors, and you have... well, a bit of a tubby car, to be honest. But one that’s as tech-heavy as it is, y’know, regular heavy.

Yeah, we just said it was full of tech, but this one deserves to be singled out.

So, you’ll notice the super sleek lines, and recognise that they may have been marred just a touch by the presence of a permanent rollover bar. You might also recognise that rollover bars in drop top cars are something of an essential safety feature. So, a pop-up rollover bar fits the bill perfectly.

But it’s the way Mercedes did it that enraptures our inner engineer – it’s hydraulic, yes, but the hydraulics actually hold it down. Hydraulic pressure acts against springs, keeping them compressed and full of potential energy. So, when the sensors and computers detect a rollover, the hydraulics have to do nothing more than unleash the beast, as it were. It takes about three tenths of a second for the rollover bar to fully extend – crucial fractions of a second before you can expect to be tyre-side-up. And even in the event of complete hydraulic failure, it’ll still work. You’ll probably get the fright of your life if the hydraulics fail while you’re just cruising down the road, but you won’t get left between a very non-metaphorical rock and a hard place if you roll.

For people in our generation, the idea of a Mercedes SL without a drop-top and without a V12 would be like a tweet without a mindless hashtag in it. And yet it took four generations of SL before the vaunted engine configuration squeezed its way under the bonnet.

Well, when we say ‘squeezed’, it was more of a... gentle letting out of the seams of the R129 SL, which had to be lengthened in the engine bay to accept the sheer size of the V12.

So, this might take some explaining. Imagine if a storm in a teacup somehow managed to flood your house, and you might have some idea of the ridiculousness of the situation.

While Princess Diana was still alive and still a favoured tabloid punching bag, she made the apparently traitorous decision to trade in her Jaguar XJS for a new 500 SL, likely due to the fact that the Mercedes did things like ‘work’ and ‘keep the rain out’. And that just wasn’t done, apparently – British royalty supported British car manufacturing, regardless of the flimsiness and postbox-sized panel gaps.

And, be it due to tradition, protectionism, nationalism or good old-fashioned tall poppy syndrome, the People’s Princess and the royals were harangued until she returned the car to Mercedes and promised to use cars from the royal fleet. And she did, arriving at her next public engagement in a Vauxhall Senator. Which was built in Germany.

Mercedes held onto her old SL in its museum in Stuttgart, displaying it among the most important cars from its history and right next to the G-Wagen Popemobile. Says a little something about the kind of woman she was, no?

… And boy, did that pan out. AMG had already done hopped-up versions of the R129 SL (and R107) before it was bought up by Mercedes, but the R129 was the first time they made it official. Mercedes bought a majority share in AMG in 1999, after years of motorsports and development partnership – running the 190E touring car and co-developing the C36 AMG, to name a couple.

Newly nested, AMG wasted no time in bringing out what has to be the ne plus ultra of the R129 SL: the SL73 AMG, with a 525bhp, 7.3-litre V12 that eventually made its way into the Pagani Zonda. In the SL, it meant 0-60mph in 4.8 seconds and a top speed of 186mph, making it the fastest and most powerful SL ever. Y’know, until the SL65 AMG that replaced it...