6 point harness - anyone using lap mounts for subs?
 

Is this acceptable in PCA events?

I've read several threads, but I've only found that SCCA allows it and some people have said PCA allows them too...but it appears it's speculation based on their best attempt on understanding the PCA rules. Anyone with first hand experience? Will the PCA allow you to mount the sub straps on the same location as the lap belts? Both lap/sub would feed through the same opening on the side of the seat. You would basically sit on the sub belts as they go up on the crotch area. Any help is much appreciated.

I believe the new rule the PCA is adopting for 2008 is that the seats must have anti-sub belt holes in the seats from the factory they were made. No rerouting belts and no making holes in seats that did not come that way.

So what this means is either stock belts with stock seats or racing harnesses with race seats. Do search on this forum and I think you will find one of the head guys from PCA posting this recently.

Interpretation of the rules aside if allowed on track it is quite workable in an '86 911 Carrera with stock power seats minus the seatback knobs.

A bracket was added to the inboard lapbelt which has a widened opening to hold the two belt clips.

Touring around streets, the 6 points stay buckled up behind the driver and passenger seat.

Workable. Roll cage recommended.

I run my six point Schroth lap belts and subs to the same mounting ring, and sit on the subs. It works pretty good. I don't really notice any difference from the previous five point that mounted under the seat. It passed tech with NASA.

i wouldn't consder it, but that's just me...I think multiple belts to a single mount (failure) point is a bad idea.

interesting, I hadn't considered it a problem. I did it to avoid drilling two more holes into the floor. I'll investigate further and change it if it presents a safety concern.

from the brey-krause site:

Some drivers choose to use a Y belt attached to the inside and outside lap belt mounts and sit on the belt. For recreational driving this type of installation works well with factory seats but it is no substitute for a race seat and traditional installation.

I wouldn't (and didn't) use it parachute style. It's just two holes in the pan. I even relocated my DME to get them in the right spot.

Don

I'll check it out, thanks.

From the Schroth website:

This would be in compliance with the manufacturer's instructions, yet against the PCA rule which requires that no two belts be attached at one mount. Quandry continues.

FWIW, I purchased new Schroth belts from IO Port Racing and they advised me regarding the installation. One of the guys there does tech for local NASA events.

This is from the Competition Manual:

PROFI 6-POINT AND HYBRID MODELS
• Anti-submarining strap routing shall be vertical down from the groin, preferably approximately 20° back.
• Anchor points shall be approximately 100 mm [4”] lateral apart from each other. In case of a a low seating position (e.g. in open wheel race
cars), this separation may be reduced since the anchor points are closer to the thighs.

Your Text seems to be for the Profi F model.

There's also a picture on page 28 that shows not running them Parachute style.

The original question here was about what the PCA allows.
Here is the new mandate.


New Harness Standard for PCA DE Events

Just posted by PCA National DE Committee Chairman Pete Tremper on Rennlist

February 5, 2007
Dear National Staff and Region Presidents,

The purpose of this email is to inform you of a change in the Driver’s Education National Standards regarding the use of safety harnesses which will become effective on Jan.1, 2008. The current “Equal Restraint” Standard states that both the student and instructor shall have the same restraint system.

The problem with this Standard is that it does not define the complete system, in terms of the type of seat to be used with a 5 or 6 point harness. The new “Harness” Standard (See below) is written to compliment the “Equal Restraint” Standard and will go into effect January 1, 2008, but a region may adopt the standard earlier.

The new standard states that if a harness system is installed, it must be used in conjunction with a seat with manufacturer supplied routing holes for the shoulder and anti-submarine belts. These routing holes insure that the belts will remain in place when needed. A one piece seat is recommended but not required for it may interfere with the operation of the OEM three piece belt required for street application.

Thank you for your help in implementing this new standard. If you have any questions, please feel free to contact me.

Pete Tremper
National DE Committee Chairman
Tremper9146@aol.com
(O)215.539.6379
(H)856.881.7049

Harness Standard
revised 1/22/07

Harness Systems:

If the participant chooses to install a 5/6 point driving harness (four point systems are not safe and therefore not allowed) several changes to the automobile must be made to create a safe occupant restraint system. Harnesses must include an antisubmarine strap and be mounted in an approved manner consistent with the manufacturer’s instructions. The Harness system must be used in conjunction with a seat which has the supplied routing holes for the shoulder and anti-submarine belts. All pieces of the restraint system must be installed in accordance with the manufacturer’s instructions.

This means that a seat is required to have the proper routing holes for the harness as supplied by the seat manufacturer for the shoulder, lap and anti-submarine straps. The shoulder straps should be mounted at 90 degrees to the axis of your spine or at most 40 degrees down from horizontal. Because the addition of the harness system means that the occupants are fastened upright in the vehicle, a properly padded roll bar or roll cage is strongly encouraged to complete the SYSTEM. The use of one without the other may result in an unsafe environment and is not a COMPLETE SYSTEM. Due to UV degradation and wear the harness webbing must be replaced every five years

I personally don't see a lot of room for interpretation. If the seat is required to have sub belt holes then this rules out sitting on the belts.
It seems pretty clear to me.
IMHO anti-submarine belts were never designed to be sat on.
It simply is compromising the system. That isn't to say that it isn't allowed in many cases.


Personally if I was going to the trouble of installing harnesses as safety equipment (which I am currently) I would install it properly.

Just my 0.3

These rules sound like they were written by lawyers, not safety experts.

Huh. Other than the single-point-of-failure issue I'm wondering if sitting on the sub-belts allows you enough downward tension to keep the lap-belts pulled down as low on your hips as possible?

I've got to believe they wouldn't because if you REALLY tighten your shoulder belts up, it would tend to pull the lap-belt/cam assembly up over your hips and onto your belly.

the physics is just wrong wrt sitting on them. The function is to keep the lap belt low. You want the force of the sub to be in as direct opposition as possible to the lap sliding up towards your midsection...that would be straight down, through a hole in the seat, and down to the pan.

If PCA states the following:

"Harnesses must include an antisubmarine strap and be mounted in an approved manner consistent with the manufacturer’s instructions. "

And the schrotch manufacturer says this:

"This is achieved by sitting on the anti-submarining straps, routing them rearwards and attaching them in the region near or on the lap belt anchorages."

What's a person to do? If we follow the manurfacturer's instructions than we should be in compliance with the PCA... right??

You should do whatever you feel comfortable with. No way I would sit on the sub and mount it back. But it's your car and your safetly, not mine.

You're right, I typically do whatever I want with my car. But that's not the issue, there's quite a few people, including myself, who are confused about the rules and manufacturer's instructions. Just trying to shed some light and hope to get some guidance that'll satisfy the PCA rules, manufuacturer's instructions and hopefully not kill yourself in the process.

Scroth seems to be an outlyer in their suggestion to mount to the lap belt mount points. Schroth also sells 4 point belts which I think are more dangerous than 3 points.

There is a reason that race seats have a slot in the bottom. I don't think it's for looks. I don't know of any sanctioning body that would dq your car for having a proper race seat and a sub properly bolted to the floor under the seat. It strikes me that the parachute style use is a workaround for a seat that isn't slotted. I used to have that issue and instead ran the sub up over the front of the seat. Not optimal, but better than nothing. But once I got more serious about racing, I went to a more appropriate setup.

In my albeit quick read of this, I did not think this was in reference to their competition line. They are very clear in the manual about how to mount the Profi harness through the substrap hole.

PCA is putting some of th liability onto the driver and the Seat belt manufacturer by making us follow the manufacturers instruction. As long as you keep your installation documentation for your belts you should pass if you mounted them by how they state.. But that does'nt mean it will be completely safe or the best way to do it ..

Thanks for the opinions. I will definitely continue to study this issue. For now, my harness is mounted per the instructions, and has passed annual tech inspection with the sanctioning body I'll be racing with. It also seems to me to be the most effective mounting method given the design of the harness, and the mounting points available. When I look closely at my setup, it seems like running the two sub belts through the sub hole in the seat would be a problem due to the 't-bar" connection at the buckle, which spreads the sub belts apart enough to make fitting them into the sub hole awkward.

http://www.schrothracing.com/ximg/1602/Profi_II_6H.jpg

Currently, the "t-bar" effectively aims the belts comfortably under my thighs, and out the lap belt holes, like the instructions suggest. I suppose the preferred method most here are suggesting would require me to discard the "t-bar" and replace it with a narrower mount point that allows the two sub belts to run close together as they go through the sub hole and then spread apart again to reach two more mounting eyes. Also, the buckle does not ride up onto my belly, because it is pulled downward by my body weight resting on top of the sub belts. The fit feels tighter and more comfortable than my five point belts did. I also don't see the difference between routing the subs through the seat or to the lap belt points. In the end, both methods keep the driver from submarining. Routing the subs under your thighs protects the jewels a little better as well.

Is there evidence or experience that shows a safety problem with sitting on the belts?

if you are in an "event" your body weight will be tossed around like it is nothing. Seems to me that the lap would then ride up if you bounce up, no?

I stick by my opinon. No sitting on subs...they go down through the seat and to the floor.

No riding up so far. The angle that the belts go through the lap belt holes to the mount point seems to be steep enough to prevent that. Is there some specific evidence of a known safety issue, or just conjecture? I'd like to know before I spend money on changing the sub straps so they'll go through the sub hole in my race seat.

Whoa, folks!!! Ten cuidado!

I have been using the internet to share p-car information since around '93 or '94. Even before Porschefans.. Porschelist... et cetera.

I remember at various times "internet folklore" about how belts could be mounted with stock seats... sitting on subs and the like. I even remember admonishing a well-know driving book author and former PCA region Chief Instructor after he convinced the region to adopt a set of mounting requirements based simply on something he read on the internet. Shameful.

There ae many great manufacturers of belt systems. These include, but are not limited to Sabelt, Simpson, Crow, G-Force and Schroth. I think most groups, like PCA, want you to follow the manufacturers guidelines. I think one should not be shy about asking them about how to deal with subs, not a bunch of people on the net. Some of them don't provide specifics for number of reasons. But it seems to me, they should be your first source.

I currently use the Schroth hybrid system for the driver and a set of FIA-rated G Force belts when I carry a passenger. The former provide detailed instructions. US Importer of Schroth is HMS Motorsports, and that is where I bought the belts. Joe Marko is the man there, and he works with SCCA, NASA, BMWCCA, PCA and even NASCAR. Yes they use Schroth in NASCAR. WHen I have questions, I just pick up the phone and call Joe, or I send him an e-mail. If you have questions about Schroth, that is a good approach. If you use something else, contact the manufacturer. If that route does not pan out, talk to professionals.. not a bunch of guys and gals on the internet.

- Mike

I think I said that in my earlier post Mike,, Follow the manufacturers instructions and you have the best source..

You did.. I was just reinforcing. Plus letting the folks know that if they use Schroth, they should access HMS/Joe if they need help. They/he are a great resource.

I once contacted Joe because the instructions for my hybrid set were a little ambigous due to poor German to English translation. The result was a set of subs that got damaged. I caught the issue when they subs were partway worn through. They would have failed in an accident.

- mm

ZOANAS

If you were to run the subs under the seat, will there be any clearance/mounting issues because of the DME brain that resides under the seat?

Parachute style is really formula style. This means cockpits where the seat is integral to the cockpit and drivers are reclined. Reclining changes the crash dynamic. People have tried to "dual use" streetcars with stock seats and avoid 5th point subs going over the front of the cushion by using 6pt parachute harness set-ups. While this works who know what that will really do in a crash. A car on the track means you mentally need to be able to write the car off. To me that means if you need extra holes to mount subs properly then do it or don't track it. Be careful to mount the subs with at least a large washer but remember that to some like me that is not adequate but many manufacterers think it is o.k.. Think for yourself...Try jacking your 3000lbs car up from the proposed sub point. If you get a big dent you need to reinforce this area. A 20g crash yields like 3000lbs on the subs. When belts come loose and slack during crashes you get hurt and can die.

No, ironically, I moved the DME behind the seat. I have the eye bolts that came in the package, and will most likely install them under the seat, and then I will have the option of either method.

Mike, I'll talk to you about it at the track Saturday for sure.

10-4. I have a bunch of extra mounting hardware if you want some.

Thanks Mike, I have all the hardware. It shouldn't take 20 minutes to drill the holes and run the belts through the sub hole.

ZOANAS,

If you don't mind, could you post some pictures and any additional info as to how/where you decided to drill/install the subs? Thanks in advance.

Sure thing. I'll be doing it all tomorrow, so I'll post pix then.

OK, removed the seat:

http://forums.pelicanparts.com/uploa...1178337851.jpg


Decided to simply replace the rear seat bracket mount bolts with eyes to mount the sub belts to:

Works like a charm, and I like the fit better. Thanks for the "push".
http://forums.pelicanparts.com/uploa...1178337924.jpg

It's a little aft, but better than to the sides. Don't forget to put cotter pins into the clips.

Thanks, Don. I agree, I'll likely add new holes further forward. I overlooked the 20 degree angle they ask for in the install instructions, so I'll fix that.