Thanks for the kind words, Stephen. We try to make seating better for tall and short racers alike.
I finally cropped the pictures from his install and figured I would share. Pictures from his install
starts here.
Here are the weights. Stock passenger seat shown at 60.8 lbs. The Recaro SPD with the Sparco slider was 33.3 lbs and our brackets were 2.8... so weight saved looks to be about 49 and a half pounds. Not bad - and he can finally sit upright with a helmet on, which is a huge plus.
The brackets we made don't look like much work, but that's deceptive. These incorporate integral long nuts welded into and through the tubes for the sliders to mount to, and access holes to bolt these brackets to the stock mounting holes in the floor. They bolt in and out easily - without having to disassemble the seat from the slider. Super short stack up height for the entire set-up. We also beefed up the washer area for the hardware from the Sparco sliders to the Recaro SPD mounting holes (the SPDs are made with M6 thread inserts, so we made a long washer to spread the load out against the slider, for use with the M6 SHCS hardware it came with).
The stock 135i front seat belt receptacles have an explosive charge in them to pretension the belts during a crash ("crazy Germans"), and are wired into the same plug as the power motors and other systems, so the front belt receptacles cannot be removed for re-used with an aftermarket seat. Instead we used a pair of
rear 135i seat belt receptacles (they use the same male buckle style) and made a solid mounting tab on our steel brackets for those to bolt to.
The Sparco sliders have a huge range of travel (18") and allow you to still access the rear seat, fit tall or short drivers, and are the safest and shortest (height of slider) slider option we've found. I'm 6'3" and fit in Stephen's 135i with a helmet on and room to spare.
These came out pretty nice. Making custom brackets for a car like this is usually a "one off", and takes much more time than you can imagine. There are very few off the shelf seat bracket/slider solutions that work for taller folks wearing a race helmet. If you are in the north Dallas area and have a "seat situation" like Stephen, we can possibly help.
Cheers,