Originally Posted by Car54
Do you know that your seat serves as the anchor points for your seat belt? Replicating that with aftermarket seats is not very easy and unproven. In addition, you have to be very mindful that the belts "ride" on your body properly, tight on your hips.
Do you also know that there's a device in the seatbelt receptacle that detonates under crash to tighten the belt (pre-tensioner) and if there's an aftermarket seat eyelet in the way, it will destroy the seat and/or damage the buckle.
All stuff to consider when you go messing around with years and millions of dollars of crash data collection and engineering.
Try a CG Lock and a volleyball knee pad on the door side knee to help brace yourself.
Most floor mounts will have an adaptor (extra cost) that you can bolt the tensioner so you can retain the 3 pt seats. Even in a sedan but you'll just need 2 of those adaptors. But, of course, not crash tested.
Again, agree and I personally wouldn't recommend fixed seats in car that is your only daily driver for safety and comfort concerns. My E46 will be a streetable track car that I will drive on the street occassionally that I will never take my family in again so fixed seats work.