Here is some guidance on how to properly install roll cage feet. The main purpose of the thread is to help our track car members who are unlikely to refer to the MSA Blue Book whilst installing a cage in a car which will not be seen by MSA scrutineers, at least not in the short term. But it will also help those preparing a race car, and draws on my experience as an eligibility scrutineer whilst liaising with the MSA scrutineers in the Mk2 Golf Race Series in 2007. So if your car is "just" a track car... you may not actually know if you'll later wish to use it in competition. BUT you can add value to it so that if you race it, the cage is done, and if you sell it, it is a car with an MSA-legal cage install, which helps with the value. So hopefully this should be useful, and add value to your car. Firstly, this is a guide mainly for bought manufactured cages, and is not designed to cover weld in kits or home brew cages (though the footplate information should still be close to right). What it doesn't cover is cage design, material thicknesses etc - please refer to the MSA Blue Book [STRIKETHROUGH]2008, page 152-184[/STRIKETHROUGH] 2009, page 156 - 189 here if a full comprehensive read is required. The thing to remember all the time is that a cage must fundamentally support the roof. So imagine when a car is dropped upside-down, straight onto the ground, and where the force goes. => straight to the cage feet. This is the main thing that occupies MSA scrutineers' minds as they inspect cars for safety before race meetings, and this applies to all Where do cage installs go wrong? People buy cages, FIA approved etc, some come with pre-formed "reinforcement plates" to weld to the bodyshell. The owner duly installs them whilst assuming all is well, and then finds a scrutineer breathing down his/her neck asking for more strengthening work to be carried out, despite the writing on the box saying everything was included. Do not rely on reinforcement plates supplied by cage manufacturers. Check the spec against this post before grabbing the MIG. Rightfully people often find the actual cage install is enough work, without having to modify the actual installation feet as they do it. Cue red faces at scrutineering, often after burning the midnight oil to be there in the first place. Shoddy welding eBay specials being acquired, made of non-current specification, sometimes minus door bars. Cue scaffold poles or other seamed tubes start getting used for door bars, instead of the required seamless tube Worth a mention that alloy cages are long since outlawed, and scrutineers arm themselves with magnets when suspicious MSA definitions: (ref: 2008 MSA Blue Book, page 152) So, the MSA blue book stipulates that all A and B-pillar cage "mounting feet" must have 120cm squared "reinforcement plates" (aka "spreader plates"), made of 3mm steel plate. That's squared - so that's 10.95cm x 10.95cm on a square plate, or another combination with a rectangular plate (with the same surface area) 10cm x 12 cm. So there's the bodyshell of the car, the 3mm steel "reinforcement plate", and then the "mounting feet" of the cage itself and the cage tube which is welded to those feet. So, three layers then - always - and this is where some track cars scrimp, and a main focus of this post. Trackcar cages without these footplates not only will never be allowed to compete where a cage is required, but could also be turned away from a sprint or hillclimb if a scrutineer didn't like the install, even if a cage isn't required in the sprint/hillclimb class. Such a cage isn't installed to do its job, and in my view a scrutineer would be negligent by allowing such a cage install to run at speed and risk injuring a driver.