morefun

Taking my DEs to the next level this coming season, I'm installing a 5pt. harnesses in conjunction with a pair of Recaro SRDs. While thumbing though one of the British Porsche magazines, I noticed a picture of a 968 Club Sport with the shoulder harness attached to the rear deck just forward the spare tire well. The angle to seat back looks good. It would appear to be a easy option, bolt in a D reciver with the appropriate backing plate. Any input? Is it doable?

Cheers

jerome951

Doable, yes.
Optimal, no.

That would be a really long belt so there would be a lot of stretch (assuming you could find a belt that long).

The mounting plates at this attachment point were likely welded in. This area (for the passenger side) is also over the gas tank. You'd likely want to drop it to safely weld there.

You also don't want the belts to be more than 20 degrees below horizontal from the tops of your shoulders. Not sure if this location is too low or not.

If you're serious about going to the next level, go all the way w/ a real racing seat and roll bar or cage. Or at least look at a good harness bar.

Just my opinion.

Jerry

Some rules say you must use existing seatbelt mounting locations. Stable Energies sells a harness bar that fits the c-pillar, above the top part of the rear seats. The belts must go over the bar and down to the rear searbelt locations.

keith

Don't do a harness bar - do a search for the safety issues there - at the least, do Hajiny's bolt in roll bar. Better, do a custom made weld in. You can cut the tubes off of the base plates a replace the carpet if you ever decide to sell the car.

dmoffitt

I actually have a spare harness bar in like-new condition, my new chassis has a cage so I have no need for it. $$ CHEAP to get it out of my already-cramped city apartment

smokey

The Weltmeister 944 harness bar is made of 1 1/2" roll bar stock, and mounts to the C-pillar with the flange in tension. I used that before I got the Redline roll bar. And I did not loop the belts down to the rear lap belt mounts.

Z-man

morefun: I used a Stable Energies harness bar before I got my redline racing rollbar.

My harness bar was attached to the C-pillars, and my shoulder harnesses were looped over the bar and attached to the rear seat belt mounting points. This setup has been debated here ad-nauseum, but most regions accept this as a valid setup. Check with your region / club to see what their requirements are. (Some state the shoulder harness must be looped over the bar, while others say it must be attached to the bar). Whatever you do, keep in mind that unless you start welding stuff to your car (which I don't think you want to do at this point), the safest attachment points are the seat belt anchor points. Also: make sure the bolts you use are all Grade 8.

IMHO, the harness bar setup worked for me in keeping my harnesses in place. Granted, it is not ideal, especially with stock (non-racing) seats, but it did serve it's purpose. Then again, I didn't crash, so I don't know what would happen in any sudden decelleration event.

HTH,
-Z-man.

RedlineMan

morefun -

Good stuff here. Pay close attention! Also spend the time to find some of the recent threads dealing with this. You will get more info than you think you need, perhaps, but you'll learn a lot!

The long belt length you talked about in your example does offer some problems in that the belts will stretch too far in a biff. You want a reasonably short belt length. 1-2' is optimal. Do the best you can here.

As for harness bars, c-pillar is best. Although this can lead to longer belts, b-pillar is not strong enough unless it is braced like a Brey-Krause. Unfortunately, this is only a "guide bar" and not for mounting. If you do get a c-pillar bar, make sure the mount flanges are in tension as Smokey suggested. Meaning, they place the bar directly in front of the mount bolts. NEVER use a bar of less than roll cage spec tubing!!!

This gets sticky, eh?

My good friends here have mentioned my roll bar, and it was designed to deal with these issues. A good option... and I DO say so myself.

morefun

Thanks guys,

I'd like to do it right. This will be my fourth year of DEs and I'm driving fast enough that I think its time to rachet up the safety margin. I had one big off in wet last year at speed (fortunately no contact) and it opened my eyes BIG time!

Cheers

Z-man

moerfun:
You are very wise in upgrading the safety devices first. Too often, too many people ignore that factor, and just focus on the 'go fast' goodies.

-Z.