fatbillybob

You shoudn't. If you buy an in service date 5 yr. FIA seat you need no back brace and no FIA seat is tested with back brace. BB was a controversial good sounding idea to deal with expired 5yr seats until you think about the intelligence of a post sticking you in the spine at 20g's. The FIA 10 yr seat was born and is more expensive and has an integral back brace anchor point. Cages need to be outfitted for the brace. Then you can use aluminum seats which deform in a crash which need multiple anchor points and back support to not deform. Rule of thumb is 4 at seat base 2 up on the torso minimum. Back brace there is anywhere you want because aluminum seats can be drilled unlike FIA plastic seats. Still you want a back brace not a back post.