We drive Derek Bell's Porsche 962

"Now remember. You're on slicks and they're stone cold. No heat or grip whatsoever. The boost also comes on really suddenly so watch out for that, especially with the lack of grip you've got at the moment."

So says Derek Bell directly into my ear. I'm hooked up to him via a pit-to-car radio in my helmet, and I'm about to step into a Porsche 962 at the Top Gear test track. Derek Bell - Le Mans legend, works Porsche driver, and my personal hero for as long as I can remember - is telling me to be careful, then things are about to get very hairy indeed.

He then follows up all the scary-sounding advice with a simple shrug, a thumbs-up, and a "but don't worry. It's quite a relaxing car to drive." Which promptly makes me worry even more.

See more pics of us driving Derek Bell's Porsche 962

This 962's reputation is formidable. Together with the closely-related 956, both cars won 232 races across 12 years, including seven victories at Le Mans. And because of that, you approach it with respect - you do not mess with a 962, or treat it lightly. This very car finished ninth overall in the 1988 Le Mans, racing in the same livery it wears today. It's got full ground-effect aerodynamics, a 2.8-litre twin turbo engine producing something in the region of 700bhp with a 235mph top speed, and it's worth about £600,000. It's an original car, in that it has the matching engine and chassis numbers from when it raced in period. In other words, if I crash it badly, a significant chunk of the value disappears. To top it all off, I'm driving it in front of the car's owner, and just one week before it disappears off to Le Mans for Derek to compete in the Group C race. It's also started to rain. Oh dear...

Time to clamber in, and even getting yourself into the driving seat is difficult. Left leg extended over the wide right-hand sill and past a bank of radiators, then both feet onto the seat, grab the roof and slide, threading both legs past loads of tubes and wires, at some point reaching what you hope is the set of three pedals. How they ever did a quick driver change in Le Mans is a mystery.

And then something seemingly incongruous - just turn a key to start the engine. This is weird. I'm in one of the most successful cars in the history of sports car racing and all I've done to fire it up is turn an innocuous-looking key in the dash. There's no pumping the throttle to bring the fuel up, no complicated starting procedure. Which just feels slightly anticlimactic.

You then have to select second gear before shifting it into first - it's a full-synchro manual gearbox, but a quirk of the ‘box means that if you go straight into bottom it graunches. Build the revs up, drop the clutch and we're away. So far, this 962 is belying its reputation - the clutch isn't brutal, the throttle feels progressive and smooth, I don't get anywhere near stalling it. It's definitely starting to feel like Derek was right about it being easy.

Pull out onto the runway at the track, and suddenly it all sinks in with a rush. I'm driving a Porsche 962, I've got Derek Bell giving me live instruction, and in the process I'm ticking so many bucket-list boxes that if my heart failed now, then I'd probably just have to shrug and admit defeat.

"Build your speed up in first over about 150 yards, then snap it into second as soon as you can. Then really boot it."

Really? Already? I'm beginning to think Derek is a little more gung-ho than me. But this a direct order from Mr Bell, so do as you're told... and oh my god this thing is quick. The turbo comes on-line in one great dollop of torque - "it goes from something like 250bhp-700bhp in that instant" - and now I see where this car's rep came from. Derek is most definitely not right about it being easy.

See more pics of us driving Derek Bell's Porsche 962

The 962 fires up Dunsfold's runway, fighting and squirming all the way. What must this thing have been like on the Mulsanne at night? It's reacting to every bump, darting and moving this way and that while I try to keep it all pointing in the right direction, wrestling the wheel. A situation made more difficult because I'm sat way too far back (there's an actual bedroom-spec pillow behind my back to try and get me a little closer). Do I really dare go into third?

"Keep the power on and really rush that change into third, then fourth." Jeez, give me a break, Derek.

Keep the throttle planted, the revs building easily, the needle sprinting round to the 8,000rpm red line, and then snap the 962 into third, the turbo waste gates chirping.

And all of a sudden the car makes sense: it becomes easier to drive. The change from second to third is far snappier than the clunky, dog-leg first to second, so you're able to keep the revs up and the turbo spinning. Once it's up in the gears and moving there's no rush of torque - you're simply in that phenomenal power band all the time.

The aerodynamics also come into play. You can actually feel the 962 sucking itself into the tarmac. Unsurprisingly it's incredibly stable -but definitely not something I'm used to. Derek was right - in a strange, super-velocity way, this is relaxing. I no longer have to fight, and because this is such a stiff racing car, there's plenty of communication through all the controls to make it feel like I've got control. Even if I probably haven't.

Except for the brakes, because the feedback through the pedal is pretty nonexistent. Derek again - "tell me what you think of the brakes. Really stand on them" - and I try, I really do, but I never get anywhere near their potential. The discs and pads aren't warm - the tyres would be hotter if I breathed on them - and so when I try to lean on the brakes I'm wary of locking everything up. Discretion is the better part of valour today.

It's time to head back in, knowing full well that I'll never get anywhere near this sort of car again. But that's not the point.

Hero racing driver met, hero racing car driven. For me, this is something entirely special. A litte gem of a day. And not bad going for a wet Wednesday morning.

This feature appears in the December issue of Top Gear magazine - which is out now. 

Click here to see more pics of our drive in the Porsche 962 and hit the play button to watch a video below.