If, like us, you’re a big fan of BBC’s Top Gear, then we suspect setting a lap time in the "reasonably priced car" is quite high on your wish list of things to do. Well, come October and the release of Forza Motorsport 4, you’ll be able to do just that.

Because not only does Top Gear’s test track (Dunsfold Aerodrome in Surrey) feature in the game’s extensive array of race circuits you can drive on, but you can select that reasonably priced Kia Cee’d (pronounced cee-apostrophe-dee in Clarkson speak) to race in.

But just how good is the game at emulating reality? To give us a better idea, Microsoft, Turn 10 (Forza’s developers) and BBC Worldwide arranged a day at the Top Gear track to compare real world with Xbox world. (I know, I know, tough job - but someone had to do it…)

Let’s get one thing straight first. Even hardened racing gamers will admit that driving a racing game’s never going to provide quite the same visceral hit as ringing a car’s neck around a race track. Even in a feebly-powered unit like the Kia Cee’d, your body’s subject to forces that you’d struggle to recreate even in the most advanced simulator. But given that one of the Turn 10 team’s aims with Forza 4 is to turn “car lovers into gamers”, and as Pocket-lint’s resident petrolhead, I have high hopes. So how do the game and the real thing compare?

First off, a few words on the real lap. If you’d like to see my somewhat embarrassing effort, you’ll have to check out the video. They weren’t allowing proper timing due to the way the day was set up, but let’s just say that it’s harder than it looks in real life and I’m sure I could have gone faster… and that when you’ve watched the TV show a thousand times (on repeat, on Dave), it’s frustrating that you can’t remember the proper line.

So, what don’t you get the sense of on TV? Well, sharper viewers will have noted that the track’s effectively a figure of eight, so you’re retracing steps at certain points which is slightly different from the race track norm. You don’t get the sense that there’s actually a bit of a hill up to the first corner, or quite how tight Hammerhead is. You're effectively turning right at followthrough - which, when you’re doing 80mph, is a little unnerving (as you’ll see in the vid, I didn’t quite turn enough…) - and clipping the curb through Chicago sends a coxis-bashing jolt up your spine that, at first, makes you think you’ve broken the car. And while it looks slow from the outside - and the Cee’d’s no Ferrari - inside the car you’re working and concentrating quite hard.

Out of the sweaty race helmet, and into the cooler confines of the Top Gear studio, which today is playing host to a bank of 50-inch Samsung plasma’s hooked up to Xbox 360s, and the first thing that strikes you about Forza 4 is how crisp and photo-realistic the graphics are. A new multi-source light generation engine means that reflections, shadows and the fall of light across the cars is ultra realistic. It’s most impressive in "AutoVista" - a kind of garage where you can walk around, get into, and fire up the cars. Not only that, but AutoVista allows you to pore over the engine bay of, say, a Ferrari 458 Italia - if that’s your thing - and none other than Jeremy Clarkson, himself, has done the voice over to tell you about the car.

It would have been easy for Forza to go all corporate here and get him to say nice things about every car, but that wouldn’t have felt like the real Clarkson. So, in an inspired move, they gave him free reign and you get Clarkson at his opinionated, analogy-filled best. PRs from certain car makers may want to skip over that bit.

Into the Forza Kia Cee’d and onto the track, and the first thing that strikes you is that everything feels right, with even the smallest details nailed down - you’ll see the 747 in the background and the tyres at Chicago are perfectly placed. Forza allows you to customize the level of driving assistance it’ll give you and, according to Brian Ekberg, developer at Turn 10, you’ll struggle to put in a decent lap with any of the assists on.

So, after a few familiarisation laps, we switch all of the assists off and go for a few hot ones. The remarkable thing about Forza, is just how real it feels. The same sense of torpid acceleration in the real Cee’d’s there, and turn too hard or while accelerating and it’ll understeer - just like the real car. Using the new Xbox 360 wireless wheel - which will be released around the same time as Forza 4 - you get terrific feedback, and it’s really easy to modulate your inputs. Forza’s worked hard with tyre maker Pirelli for the fourth generation of the game, in an attempt to create really authentic feel and response with each car, and it shows. Only the brakes let the side down, grabbing and pulling the car up much more effectively than they did in the real world!

After a good hour of practice, the best laptime I could manage was a 1.47 - some way off the top of the real world Top Gear board. But the key is that the lap felt real, the car felt right and it’s truly addictive. Just as you’d want to keep going round in the real Cee’d to post a better lap time, so Forza keeps egging you on to improve your best lap.

The best news for Top Gear fans is that, not only does the game feature Jeremy and the track, but some of the fun stunts from the show, such as "car bowling" where you knock down cones, and the infamous "car football", played with Toyota Aygos (season eight for those interested). That’s just a small selection of what looks to be a truly brilliant racing game, and we suspect that, come the autumn, house parties and forums will be full of reasonably priced car Top Gear lap time competitions. Be warned, it’s addictive stuff, and the next best thing to going round the track in the real world.