Sorry I’ve missed this thread until now. Sorry also for my long reply. Going back to the OP’s question…..
Although I’m a landscape photographer primarily, I’m a huge motorsport fan. I compete in local motorsports (supersprints), and am a F1 junkie. I’ve gone to just about everyone of the F1 Aus Grand Prix since the mid-80s (Adelaide and Melbourne) and have photographed at Monza, Monte Carlo, Shanghai and Singapore. Have not done Sepang though, although I’ve driven past it a few times.
My thoughts are:
1. Preparation is key, and you’ll get your best motor racing images on the Fri/Sat rather than race day. Study the map of the circuit and determine which is the best corner for images. If you can walk around the circuit on the Thursday so you can plan where to shoot when the F1s do the practice sessions on Fri and Sat. For example side on to a straight is generally useless, but head on can provide for some dramatic action. For panning, I like to find a slow corner, where the cars can accelerate from an initial relatively slow speed. This allows your AI servo /AF tracking to lock on easier than trying to lock on at 300km/hr.
2. Race day is a day to enjoy the race. Take your images during Fri and Sat practice or qualifying. If you can get a multistand ticket (diff stand Fri/Sat/Sun) that is great so all your photos don’t look the same. However, a lot of venues allow you to go to any stand or any part of the circuit on a Friday. Also check out the entry criteria for photography. At the Aus GP max 300mm lens can be used, and they police white lens bigger than this (although you can mostly sweet talk your way around this). At Monza/MonteCarlo/Singapore – they don’t care. Not sure about Malaysia.
The ideal corner has a tight entry, opens out onto a long enough straight for you to get a smooth panning action going.
3. A lot of the grand prix tracks, and I suppose Malaysia is no different, are surrounded by wire cage. It is often impossible to get above the wire to shoot in the corner you want, so I get as close to the wire as possible and shoot through it.
Shoot with the lens wide open, get as close to the wire as possible, and avoid direct sunlight on the wire. The depth of field will render the wire virtually invisible. All my best images have been shot through the wire.
4. Regarding focusing through the wire – I use the 1dx so the AF tracking (option 1 or 2) is exceptional. During panning, once the AF locks on, it just doesn’t let go. My keeper rate is a lot higher than when I was using the 5d2 and even the 1d4. Yes you can manual focus to a predetermine part of the track, and this works if you want to freeze the car at 1/2000 etc. However I find static motorsports images fairly boring and prefer to pan. Once you pan, manual prefocusing is obviously problematic. Much better to use AI servo.
5. If panning, shutter speeds will be in the order of 1/30 – 1/100, depending on the corner and the speed of the car. If you are shooting wide open to use DOF to render the wire invisible, your shot will be overexposed on bright days even at ISO 50-100. I therefore always carry some ND filters, Generally a 3 stop is enough. As my primary lens are the 300 f2.8 or the 400 f2.8, I carry drop in NDs. If using the 70-200, a front screw in 2-3 stop will be more than adequate.
6. Although I have a 400 f2.8IS, and can shoot it hand held, or with a monopod, I find the 300 f2.8IS more versatile and more than enough at most tracks. You can shoot all day with it, don’t need a monopod, can move quickly from corner to corner. Add a 1.4III extender if you need more reach. Also don't forget a wide angle for colour and atmosphere.
Some of my images from G+:
As I can’t sell F1 images without permission, I don’t have many on my website: