Yet another seat belt/harness Q!

[shmoov69]

Ok, I would like some honest and real world answers if I could. I know that there is a difference between "ideal" and "real world".
My car has stock seats and belts. I just put in a 6 point bar with a cross bar behind the seats.
I want to get some real belts for the events and just general safety because, well frankly the car is just too friggin fast to not have them! I do not want to have to get "custom" seats because I like the (1) cost, (2) style and (3) look of the stock seats in my car.
So, all that being said, what is going to be my best "real world" option? I have looked into the Scroth (or whatever it is called) 4 point belts and also the G Force Pro H 5 point harness, which has a sternum belt to connect the shoulders together.
1) Can the 5 point be used without the crotch belt?
2) Would that belt be better than the standard 4 point since it has the sternum connector?
3) how does it compare to the Scroth belts? Other than less $$
4) how bad will the belts "possibly" slide without the locating holes in the seat and would it "work" by going under the headrest?
5) how could it be worse than just a lap belt or the oem style 2 piece belts? Real world here, not "ideal". Mainly IMO because if I'm in a wreck hard enough to "fall out" of a seatbelt, then I prolly will have a LOT more issues to deal with.

I will only use the lap belts except when racing because I will have the cross bar removed and the shoulders will be attached to it.

Anything else? I just need to get this done ASAP since the MMCC is coming up in a few weeks and the car is FINALLY going again!!

Thanks guys.

[parsonsj]

Hey Jimmy,

These two sentences are inconsistent:


I want to get some real belts for the events and just general safety because, well frankly the car is just too friggin fast to not have them!

I do not want to have to get "custom" seats because I like the (1) cost, (2) style and (3) look of the stock seats in my car.

The seats, restraint system, and harness bar need to work together. If you want to participate in motorsports events, you owe it to yourself and your family to do it right. AutoX at less than 40 mph is one thing... road racing and drag racing in excess of 100mph is another. Be careful out there whatever you do!

jp

[Gitter Dun]

Hey Jimmy,

These two sentences are inconsistent:




The seats, restraint system, and harness bar need to work together. If you want to participate in motorsports events, you owe it to yourself and your family to do it right. AutoX at less than 40 mph is one thing... road racing and drag racing in excess of 100mph is another. Be careful out there whatever you do!

jp

X2, what he said. If your looking to save some money on seats I Think Corbeau's are the way to go. Looking at close to $1000 with brackets for a pair and possibly with harness's.

[CarlC]

I too did not want to change the seat, but in the end there was no good choice. The stocks seats do not lend themselves well to either a comfort or safety requirement. They are like sitting on a block of ice. I had a very hard time making the switch, but have zero regrets.

We'll spend thousands on pistons, transmissions, tires, etc. but are reluctant to break out the wallet for the most important interface our body has with the vehicle.

Keep an eye out in your local area for used seats. I picked up two Sparco seats in the correct color with brackets for $500 but it took six months of scouring the classifieds.

[sik68]

+1 to everything said here! Once you site in a truly supportive seat, you will never look at your stockers the same way again. And you're only 4 bolts away from swapping them in-out if you really want to. You already put a cage in, that's the hard part...might as well finish it off.

[shmoov69]

I just like the look of the stocker houndstooth and style. But cost is an issue also, but I see you guy's point. Like always, I want my cake and to eat it too!! So, there is no good way to "make it work" without new seats? What is the thoughts on the G Force belt with the sternum strap? Will that work like I'm thinking or is it for something else?
Thanks again guys! I respect the heck out of your opinions, that is why I wanted to know the real world thoughts, not just the sales pitch thoughts!

[JohnUlaszek]

AutoX at less than 40 mph is one thing... road racing and drag racing in excess of 100mph is another. Be careful out there whatever you do!


Loads at relatively low speeds can be surprisingly high. The following is from Schroth's testing (http://www.schroth.com/installation-instructions/en/03_anchorage_locations_and_geometries.htm) at 31mph and they increase exponentially with speed:

What happens during a frontal impact:

This data is based on an optimised installation with an upright seating position during dynamic testing. It simulates a 90° head on collision, utilising a 75 kg [165 lb] mass dummy, an impact velocity of 50 kph [31 mph] and a stopping distance of approximately 400 mm [16”] with a maximum deceleration of 30 g [FIA Standard 8854/98 dynamic test requirements]:

· The pelvic load, expected to surpass 14 kN [3,100 lb] at each side, will elongate the lap belt and compress the tissue on the pelvis. The pelvis will slide forward by 80 to 100 mm [3”-4”]

· The upper torso load is expected to surpass 7 kN [1,550 lb] on each strap, will elongate the shoulder belts, the upper body will roll in, the adjusters will move up the chest by approximately 200 mm [8”] and forward head trajectory will be up to 400 mm [16”]

· The pelvic movement combined with the shoulder belt forces will load the anti-sub straps to more than 6 kN [1,320 lb] each in a 5- or 6-point racing harness and can be intentionally higher in a F‑type model where the anti-sub straps are routed rearwards.

In more reclined seating positions, the pelvic load will be reduced to approx. 9 kN [2,000 lb] since the seat pan, designed as a ramp, will take some of the load. Therefore it is essential the seat or chassis manufacturer ensure the seat pan is strong enough not to bend or even collapse under extreme loads.

In any case, seats are a significant component of the safety system!

[shmoov69]

So, is using the 4 point belts with stock seats more "unsafe" than the 40 year old stock belts? Because at this point belts are about all I can afford to spend on the car, with all the other problems I had this year with it. And I want to be as "safe as possible" with what resources I have right now. I guess the next "upgrade" after this will be seats.
So, stock old belts with stock seats OR one of the belt styles I mentioned with stock seats until I can get good seats?

Sorry to beat a dead horse, but just trying to figure all this out.
Thanks again guys.

[parsonsj]

Jimmy,

Your question is impossible to answer. Nobody knows. Check out these documents, and see if they give you some answers you can live with:

http://www.hmsmotorsport.com/docs/How_To_Choose_A_Seat.pdf

http://www.hmsmotorsport.com/docs/Competition_Instructions.pdf

Be safe!

[shmoov69]

Thanks John, now I want to go and put airbags in the car and wrap it with bubble wrap!! LOL!

Seriously tho, on that second link, on page 22 it shows acceptable and non acceptable seats and the two on the left look like the 69 Camaro seat design. What is the scoop on them?

Thanks again!

[shmoov69]

Ok, after doing a lot of looking and searching, it looks like Scroth has a 4 point that works for factory seat cars and the inner shoulder belt "tears" at a different rate than the outer and acts like a 3 point in a crash. Or there is a 6 point that you can "sit on" under your butt/legs and up thru your crotch and serves as an anti submarine belt.

I know different seats are ideal and may come later, but for now.......thoughts?

[The WidowMaker]

remember that a lot of guys dont like a 4/5/6/7 pt harness without a cage or roll bar. some say that in the event of a roll over the harness will keep you upright while the roof collapses. im still debating whether to run a 4 pt without a roll bar on anything but a lower speed autocross. although a roll over is still possible, the roof compression will obviously less during low speeds.

[thunderzy]

I'm no expert but I just went through this same dilemma. I wanted sport seats with a harness type belt for safety, as I intend to do track days. I learned that there are 2 schools of thought on the matter. It's split between absorption and rigidity. That is there are seat/ harness combinations designed to absorb and deflect the energy of an impact and setups that are designed to keep the body contained as much as possible during impact. A rigid setup always involves a cage or roll over protection of some kind. Since you already have that you are 1/3 the way to completing a rigid containment system. The other 2 pieces are usually a fixed back seat and harness.

I chose to run a roll bar, with fixed back aluminum seats and 6 point harness. Which ever way you choose to go make sure you put the pieces together properly the first time around. It'll be cheaper in the long run. I made this mistake and it has cost me. Again I'm not an expert, but that's what I've learned.

[shmoov69]

Thanks for the info! What was the "1st" go around mistake?

[thunderzy]

Sport seats, 6 point harness, and no roll bar. They were not ASM belts and were meant for a bar. I didnt do my research and bought these items on a whim. Stupid thing to do. I got schooled when I posted a how to install thread on a different forum. I decided to rethink the entire set up. I sold off the parts I rushed into buying at a considerable loss. Now I'm running a autopower 4 point roll bar, ultrashield fixed back aluminum road race seats, and schroth clubman 6 point harness. All of these are in my 79 firebird road course track car. I'm not fast at all, nor am I anywhere near going wheel to wheel racing. But the added safety makes me feel a bit more confident. Good luck with your project.

[parsonsj]

Hey Jimmy

I don't want to offer advice, because I'm not an expert. But I do think you're on the right track with the Schroth 4 pt setup... as you've found they offer asymmetrical shoulder belts that induce a torso twist in case of an accident, and that can really reduce submarining, which is a big problem with 4 pt harnesses (since the tighter the shoulder harness, the higher the lap belt lifts).

Here's an article I wrote for Super Chevy a few months back... it's got some safety stuff in it:

http://www.superchevy.com/technical/interior/upholstery_seats/sucp_1108_drivers_seat_ergonomics_unfair_takes_a_s eat/index.html

[shmoov69]

I appreciate it JP. I understand where you are coming from on the advice, I just hate that it has to be that way. That we (America) have to stay "gray" for fear of legal action. But, it is what it is!

Anyway, what is your thought (off the record! LOL) on the 6 point that you "sit on" and goes up to the latch between your legs for the anti sub part?
Thanks! I owe you a soda one of these days....heck I'll even make it one of those expensive race track sodas!! LOL

[parsonsj]

Anyway, what is your thought (off the record! LOL) on the 6 point that you "sit on" and goes up to the latch between your legs for the anti sub part?That's what we're running in Unfair. That 6 pt system is probably the best setup there is. Now... you've got your body securely lashed into place, and you get in a crash at 120 mph. What happens to your head, and its 4 lb. helmet? That's where a HANS device comes in. You should investigate that too.

My reluctance has nothing to do with liability and civil court actions. My reluctance is because I'd feel awful if something bad happened! You really need to talk with an expert... not just us guys here on PT.com. Read my article I posted above; I mention the right fellow in the article: Joe Marko at HMS Motorsports. He consults with NASCAR, and attends nearly every race to inspect/consult/advise the race teams.

[shmoov69]

Thanks John. I will prolly go with a 6 point for now, it may make me fell safer.
I tried to call both Scroth and G-Force and talked to the tech lines and they were REALLY vague with suggestions. They both told me to call a local race shop for suggestions, if there was one available. So that is why I assumed (yes I know! LOL) that the grayness was for legalities.

[parsonsj]

Good luck with on your quest! Let us know what you end up with.

[JohnUlaszek]

I've posted this link up in other threads as well, but I had a lot of the same questions and covered how I approached the problem in an article as well http://www.gmhightechperformance.com/tech/miscellaneous/1009gmhtp_sparco_seats_s_w_rollbar_install/viewall.html

[shmoov69]

Thanks John. So what did you end up with?

[wmhjr]

FWIW, I was in the same circumstances. Here's what I chose to do.

1) Built a removable 4 point rollover system. Bolt in. Not necessarily "within spec" but far better than anything else I could do. Designed and fabricated not just based on my own crazy thoughts, but with the help of a chassis fabricator.

2) Bought a set of pretty inexpensive racing seats. I bought (based on advice from somebody here) a set of Arizen seats.

3) 6 point G-Force camlock harness.

During track days, the roll bar, racing seats, and full harnesses are used.

It takes me approximately 1 hour to remove the roll bar, racing seats, and swap back in the factory seats for normal "street" use. I use the "lap" portion of the G-Force harness, tuck the anti-sub belts under the seat and keep the shoulder belts on the roll bar when removed.

Without a convertible, you'll probably find a "removable roll bar" pretty difficult, but you DO have the option of a removable shoulder bar and it would likely be far easier. I do NOT like using my car on the street without helmets, and with the roll bar. If I have to for limited use, I will. However, it's not recommended.

[shmoov69]

My rear crossbar and door bars are removable. They are the bolt in kind that fit super tight, not the pin/pull type. I was thinking using the lap belts only when not racing and having only the hoop in the car.
Thanks!

[shmoov69]

Well, I got a 6 point G-Force harness for both seats. Not the most comfortable thing in the world with stock seats, but I think it'll definitely keep my arss planted!
Thanks for the input guys!