A question we are often asked is, what’s the difference between the 500 SL R107 and the 300 SL R107? Which one should I choose and why? The 500 SL has the meaty V8 and can be more appealing to the collector community, but the six-cylinder is lighter and more economical. How do I decide and what are the key characteristics and issues to be aware of?
We’ve put together a brief guide to help you make that oh so important decision on whether to choose a 300 SL or a 500 SL. You might be surprised…
WHY CHOOSE THE R107 300 SL?
For years the 500 SL has been considered the crème de la crème of classic Mercedes convertible motoring: with celebrities and members of the public giving the model more airtime than its siblings since launching in 1980. However, the 300 SL surpassed the 500 SL in terms of global sales, with over 13,000 units produced in just four years. The result?
A LARGER AVAILABILITY OF 300 SLS
An abundance of good quality cars is more widely available here in the UK and abroad, all finished in a wide array of colours; some with the options customers paid handsomely for back in the eighties. In fact, SLSHOP saw a higher volume of 300 SLs sold over the course of the Pandemic, suggesting a shift in preference away from the 500 SL in favour of its nimbler sibling; possibly due to the limited availability of the 500SL.
CHARACTERISTICS OF THE 300 SL
A 300 SL is lighter and nimbler than the 500 SL – characteristics not widely associated with the R107 SL but drive a 300 SL and you’ll notice that the balance of the lighter engine offers sharper and slightly more responsive abilities when cornering. Couple this with the crisper exhaust note and you have a sportier feeling car with the guaranteed comfort and modern conveniences of a luxury Mercedes-Benz.
A 300 SL is quite frankly more economical in real-world conditions, achieving high twenties when cruising on motorways over long distances. This makes the 300 SL more suitable and affordable for someone with intentions to use their R107 more regularly for daily commuting as well as long-distance trips.
The 300 SL badge also carries a larger portion of the heritage of the SL lineage, adding a splash of provenance that connects this R107 SL variant to the original 300 SL that started it all. To some, ‘300 SL’ should be the only 5 digit alphanumeric insignia attributed to an SL.
300 SL MAINTENANCE REQUIREMENTS:
The 300 SL’s M103 engine is renowned for not carrying much stress and are often referred to as ‘bomb proof.’ However, as mileages rise and the lack of use plagues many of the available vehicles, the valve stem seals can wear, and the radiators can become blocked. Cars left standing with a tank that is not full to the brim are likely to have rusted, meaning the injection system will be flawed and engine operation dysfunctional.
In 1985 all R107 SLs were fitted with a modified electronically controlled mechanical injection system – the KE-Jetronic can sometimes cause the car to idle too high. This would be noticeable as soon as the ignition was started – you would also notice a higher consumption of fuel.
From experience with low-mileage 300SLs that have been static for long-periods of time, there is likely to a failure of the transmission drive when left unattended. This is particularly the case with low mileage examples. This would indicate a full gearbox refurbishment.
If choosing a 300 SL, the main thing to do is service your vehicle regularly and avoid leaving it exposed to the elements over long periods of time and without use. For a more comprehensive guide on the issues associated with the R107 model, read this article.
WHY CHOOSE THE FLAGSHIP 500 SL?
Introduced in 1980, the 500 SL is the R107 SL variant with all the accolades of an Oscar-winning actress. For years, the enthusiast has proclaimed this as the one to own, but why? What makes it better than the 420 SL or the 450 SL? These are questions that are hard to answer, particularly as the 500 SL is now over 40 years old and out of context with the popular culture of the time. But here’s a brief outline of what makes the 500 SL a strong contender…
A STRONG INVESTMENT OPPORTUNITY
The global appeal of the indestructible and raucous Mercedes-Benz M117 V8, as well as the low production numbers and availability of low mileage vehicles in premium colours, has resulted in a shortage of high calibre 500 SLs. If you see an opportunity to acquire one, this is undoubtedly a sensible investment opportunity. Prices are stable at a high level and unlikely to diminish considering the pervasive obsession with this R107 SL variant.
QUINTESSENTIAL CHARACTERISTICS OF THE 500 SL
With the larger engine displacement, the obvious difference to the 300 SL is the low-end torque, which is easily deployed from stationary. A 500 SL is a more consuming experience – the throaty bellow combined with the immediate rearing of the nose when accelerating is quite an engaging and exciting experience.
The 500 SL has some of the quirks of American Muscle Cars – a possible explanation as to why the Americans were so impressed by the R107. At motorway speeds, the gearing allows passengers to cruise effortlessly over long distances without too unreasonable fuel consumption. Of course, the 300 SL is much better in this category. On B Roads, a 500 SL is a tad heavy at the nose, making it more challenging when taking sharp corner but still a thoroughly enjoyable drive.
The 500 SL was often specified with an abundance of optional extras, including air conditioning. Standard options also included cruise control, making longer drives a lot more pleasurable and on par with modern vehicles. The 500 SL is an extremely competent and relaxing continent cruiser that will forever be in high demand.
THINGS TO BE MINDFUL OF:
A significant portion of the 500 SLs in existence are majority high-mileage examples. While the M117 engine is extremely dependable, it is common for hydraulic elements to become worn, resulting in a tapping noise emerging from the top of the engine. If choosing to purchase an R107 with 100k or more on the clock, have the timing chain inspected and renewed immediately.
The exhaust manifold is notorious for cracking and causing blows from the manifold and EGR system. Oil leaks from the sump can become common and are expensive to fix. Look out for trails of oil beneath the car and evidence within the engine bay itself. More expensive maintenance includes the drive chain, which can become sloppy and clunky over time, with excessive play when shifting gears.
A high-calibre 500 SL is less common for a reason. They were extremely admired when new and remain so in the 21st century. This means that you should be more astute when choosing to invest in one. Make sure you have a specialist lined up to support you to ensure you can make the most of your investment.
THE ALTERNATIVE FLAG
Those that are unwaveringly committed to the V8 setup have the alternative option of the 420 SL variant. Launched at the tail end of the R107 SL’s production, the 420 SL offers similar driving traits, luxury and lifestyle opportunities as the flagship 500SL. Due to low production numbers, the 420 SL is less common on our roads, but this doesn’t necessarily mean a higher asking price; it therefore could be a better alternative to the 500 SL. Find out more about the 420 SL by reading this dedicated article.
HOLDING UP YOUR FLAG
When buying a R107 SL we highly recommend you have the vehicle checked out by a specialist to ensure all mechanical components are intact. SLSHOP’s Vehicle Health Check service is the perfect way to inspect your newly acquired asset. We will carry out an indepth inspection of your car on the road and on our ramps, outlining any improvements you may or may not need to make.
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