docwyte

Ok, I've got a set of Schroth Profi 2 harnesses that I'm currently running as a 4 point, just the lap and shoulder belts. They have the ability to add a sub strap, either a 5 point or 6 point.

I need to get a set of seats for the car anyways, and I'm debating between a "normal" seat and one that has a hole cut out for a sub strap, which I'd then add.

I do auto-x and DE's with the car, no "real" racing or wheel to wheel stuff. Do you guys think a sub strap is a good thing to get, or am I good with my current 4 point setup? (I do have a rollbar in the car...)

-josh

jerome951

Hey Josh,

Rule #1 for track driving: Do not skimp on safety...
For track driving, most PCA regions will not allow 4 point belts.

The sub will keep the lap belt from riding up on the soft tissue of your abdomen in an impact. Not something you want to have happen.

Funny how people don't think that the magnitude of a crash in a DE or a 'real' race are different. You will be carrying the same speed in a DE, just (typically) less chance of an accident.

From recent research, apparently 6-point belts are better than 5-pt at controlling hip & torso movement in side impacts.

docwyte

OK, next question is, what routing choices are there for the sub strap? Ie, is the hole in the seat the only way to go, or can you loop the sub strap over the bottom cushion, etc?

special tool

They shouldn't even sell 4 point belts.

ninefiveone

Don't loop any sub strap over the front of a bottom cushion. That positioning will allow for too much body movement down and under the lap belt

If you don't have a sub hole in the seat, this is another reason to go with a 6 point setup. The sub belt ends can mount to the same point as the lap belts but run under your thighs and up to the buckle. There was another thread recently about this on the racing forum, I believe.

jerome951

I had the 6-pt sub strap setup that Hugh mentioned on my car for a couple years. Seemed to work fine though there were some 'uncomfortable' moments when tightening the belts.. This is better than nothing, but not as good as having the sub strap routed directly downward.

FYI, many instructors will refuse to use the 6-pt setup where the strap runs under the thighs. If you're required to have equal restraints for both driver and passenger, you may be running with your factory shoulder belts sometimes...

ninefiveone

Some instructors refuse becuase they're under the mistaken impression that the sub should run over the front of the seat bottom.

Obviously it's too complex to try and explain to an instructor who's debating whether to go out with you in the pit lane... but what can you do?

mroberts

Aren't there issues with having too much harness without a roll bar / cage ?

If you have a sub belt, but no cage, the belt will stop you sliding down as the roof pushes on your head.

Bob Rouleau

1) I am not aware of PCA regions who refuse the use of 4 point belts. Certainly ours, (Rennsport) does not refuse them. On the other hand we feel that personal safety is the responsibility of the driver not the region. Fact is a 4 point is useful for controlling body motions undeer the stress of braking and hard cornering. It is not useful for safety purposes. In fact it may be a hazard.

2) Without a sub-belt the harness itself is rendered nearly useless.
John (redlineman) is an expert and will probably chime in).

3) The sub belt must be close to the body so as to minimize acceleration forward. Those that allow your lower body to move forward 6-10 inches are useless.

4) Get the seat with a hole in it. Get one for the passenger side too (equal restraint rule).

5) Do not assume that because it is DE that the risk of injury in a crash is less. I agree that the risk of a crash is lower in DE but if it happens, (tire or brake failure - I have seen both) don't try and convince me that the laws of physics know the difference between a racing crash at 100 MPH and a DE crash at 100 MPH.

6) I personally refuse to wear a full harness in a car without a roll bar or cage. John H feels different and his opinion is NOT wrong. We are allowed to have different feelings on the subject.

Regards,

eniac

The shoulder harness is also an issue in non-cage cars. Stock shoulder belts are designed so as the roof panel crunches in, as in the case of a rollover, the belts will allow the occupants upper body to move inward also. Without a cage the roof can still callapse yet a shoulder harness would keep you upright in your seat.

We have a local junk yard that I often walk through on part hunts. I've seen more then a few cars that had survivors yet the back of the seat would be completely bent. If the occupants were straped into the seat, I can just imagine their back suffering the safe fate as the seat. Not pretty.

Roof + head contact = lucky if you walk away without a broken neck

Bob Rouleau

eniac - I am with you on this. Others do make a valid case that roll over resulting in collapse of the roof is a rare thing and that the benefits of a harness in the majority of incidents outweighs the risk.

For myself, I have GT3 seats, Schroth harnesses with anti submarine straps coming out of the seat (slot provided) and the Porsche Tequipment roll bar. Not as good as a cage but I drive my car on the street too.

docwyte

I have John H's rollbar in the car. I'm trying to get my order in for the Recaro Speed seats with the sub strap hole and the 6 point Schroth sub strap for my profi 2 harnesses, but I can't seem to get a return call from my vendor. Very frustrating!