Mounting harnesses to the floor/tunnel

[FredK]

I have Massive sidemounts that use the stock front studs and rear bolts to secure a race seat to the floor.

My question is, how and where do I secure the sub straps and lap belts? For the lap belts, can I use the rear bolt holes and thread eyelets into those bolt holes instead of bolts? And do I drill the floor for a couple eyelets/eyelet plates underneath the seat for the anti-sub straps?

Thanks!

[SlapDash]

Guten Tag!

Ax Murderer here.

I just lay my belts over my lap so it just looks like I'm wearing harnesses. That's what all the cool kids do.

My subs and laps go straight through the floor with a big eye bolt with a plate and a captive nut on the other side. That works for Rally America, not sure on other sanctioning bodies.

[FredK]

My normal method of using sisal rope to bind myself to an E30 sport seat won't be allowed this season, so I'm looking to upgrade a little. Maybe I'll consider some marine rope.

[Massive Lee]

All anchoring points shall be thru the floor. That's wha FIA and US racing organisations require. And don't forget thick washers behind the sheetmetal.

The outer lapbelt mounting point could be done with an eyelet bolted to the threaded hole where the original belt's slider bolted.

The inner lapbelt mounting point could be done thru the tranny tunnel. Don't forget a washer.

Both crotchbelt mounting point should be at the vertical of the seat's slot between your legs, or no more than one each rearward.

[SlapDash]

My normal method of using sisal rope to bind myself to an E30 sport seat won't be allowed this season, so I'm looking to upgrade a little. Maybe I'll consider some marine rope.

Or you could try some crepe paper, for the vintage look. With some hand-lettered 'Scroth' logos in Crayola and Sharpie. The techs will never know the difference...

I had some pics somewhere, but can't seem to locate at the moment. I know one thing that prevented a smooth scrutineering pass was not having cotter pins in the little clips that go on the eye bolts.

[JRKOUPE]

Lee has it gooood....altho Im not 100% what he means by "vertical of seats slot?.."

Yup..u gots to drill thru floor, for sub belts....BUT!...VAC has a sub belt thang now that eliminates the need to drill thru floor.

do a search for harness installs...Schroth and others have good write ups.

http://www.schroth.com/installation-instructions/en/03_anchorage_locations_and_geometries.htm

[Massive Lee]

[FredK]

Thanks, this is great information! Do you guys have a preference for bracket vs. Snap in and eyelet?

[Massive Lee]

I suggest to use eyelets (#700050/60) on the floor for crotchbelts and lapbelts, and snaphooks (#700030) at the ends of crotchbelts and lapbelts. Be carefull with the angle of the shoulder belts. 0° (horizontal) down to 10/15° maximum. Lower than that and your risk spinal compression under impact.

[FredK]

Great, thanks for replying, Lee! Hopefully I can get all of this stuff installed for a track day in May!

[Massive Lee]

The reason why I like eyelets and snaphooks is because if you want to work inside the car, you just need to unhook the harness and it is out of the way... If you want to readjust the straps, you can unhook them, adjust outside of the car and refit. That's very practical...

[JRKOUPE]

yup......Lee is spot on...

youll love such a set up.

[matthugie]

Seat and harness are one of the best investments I ever made. Such a huge difference in driving feel. As usual Lee is spot on, and pretty much exactly how mine were done.

[TobyB]

The down side to the eye bolts is that they add 1- 1.5" to the height of the mount.
Sometimes it matters, sometimes it doesn't.

t

[FredK]

Right, I am not super tall so my bet is that I'm going to have a decent amount of space under the seat.