Fixed Back Seats + Stock Belts?

So I’ve been saving up for the last couple of months for a fixed back bucket seat for the Genesis Coupe. With the kid and all, a reclinable seat is just way too expensive and the car is a weekend car so it doesn’t see that much road time.

So my question for you guys is what should I do about the belts? With the stock belts, the lap belts aren’t really snug around me it somewhat hangs on the frame of the seat to the point where I think I might submarine in a frontal crash

Should I just get a 4 point harness? I remember reading something a decade ago that you shouldn’t get a harness unless you have a roll bar. Am I suppose to get a roll bar now or was that some sort of internet myth that someone made up.

How are you guys approaching this?

I wouldn't wear a harness without a HANS. You risk neck injury due to your upper body being immobilized but your head being free to flop around. A harness is a component of a whole system and isn't compatible with street driving. 

Is there a reason you can't run the stock belts through the harness holes? Usually you have to unbolt a leg of the three point and thread it through, but generally it's possible to make it work. 

You can get run lap belt through the left side of the seat just fine. The problem comes with the buckle side because of the high bolstering. It doesn't really make contact with my pelvis once buckled and leaves a little gap which doesn't feel all that safe to me. 

Been searching the forum it looks like people are running a lot of harnesses, I just get paranoid with these things.

I hate to say it but can you get a seat with less bolstering. It really sounds like you have to much.  After years of building street cars and race cars and trying to make one do both I came to realize you really can't.  To do both you always have to compermize things. It sounds like you may have run in to that conundrum.  

Can you fit a Seat belt extender thru the seat?

In reply to dculberson :

I believe that with a HANS is vastly preferable, but we considered a harness to be an improvement over not-a-harness for a long time before it was invented. My intent here is to raise a question, not state an opinion. Dual purpose car safety is of interest to me.

That of course doesn't address the issue of whether it makes sense without a roll structure.

Schroth belts are the only ones that are approved for road use. One side is designed to extend a little in an impact, so your body turns a little. They have a video on their website.

In reply to Ransom :

Time yields more research and experience, and in my opinion time has shown that a tight 4+ point harness without head restraint is worse, safety wise, than a 3-point belt with engineered in give. Spinal damage up to and including internal decapitation are very real risks when your upper body can't move but your head can. With a 3-point your body moves enough to mitigate that risk.

"We" considered smoking to not be harmful for decades, and asbestos was a miracle material - both positions that turned out to be very, very wrong.

We've had members of our own community seriously injured driving their challenge or race cars on the street. The safety systems that help when fully utilized on track can seriously hurt when only partially used on the street. (Meaning, no HANS, no fire suit, no helmet, when wearing a harness in a caged race car is much worse than riding in a fully street-safety equipped modern street car.)

In reply to Hal :

I never thought of that...

Thanks!

Ransom said:

In reply to dculberson :

I believe that with a HANS is vastly preferable, but we considered a harness to be an improvement over not-a-harness for a long time before it was invented. My intent here is to raise a question, not state an opinion. Dual purpose car safety is of interest to me.

That of course doesn't address the issue of whether it makes sense without a roll structure.

Yeah, the idea that a 5-point harness without a HANS is less safe than a 3-point harness I find somewhat mind-boggling.  Don't get me wrong, I own a HANS and use it every time I go on track, but if 3-point belts are safer, does that mean F1 drivers should have been using 3-point belts in the 90s?  That's nuts.

That said, 5/6-point harnesses for the street are a terrible idea.  They're annoying to put on, they don't self-tighten, they're uncomfortable to wear for long periods of time, you can't get your phone or wallet out of your pocket without taking the belts off -- hell, in some cars you can't even reach the volume knob on the stereo without taking the belts off.  Maybe for a car you drive once a month in the summer, but not for anything approaching a daily driver car.

I have fixed back seats in my Miata (Recaro Pole Positions) and they have a low enough corner to work with factory belts for me.  YMMV.

codrus said:

Yeah, the idea that a 5-point harness without a HANS is less safe than a 3-point harness I find somewhat mind-boggling.  Don't get me wrong, I own a HANS and use it every time I go on track, but if 3-point belts are safer, does that mean F1 drivers should have been using 3-point belts in the 90s?  That's nuts.

A 4/5 point being worse than a 3-point is mostly applicable in a "normal" car.  A 4/5 point racing harness is designed to have zero give, so that when you crash you stay attached to the seat.  The HANS extends that by keeping your head attached to you (and attached to the seat).  With 3-point belt on a street car, there's quite a bit of give designed in to the belt, ratchet mechanism, and seat.  Remember that the belt mostly exists to slow you down enough and aim you at the airbag.

In a racecar, you're also much much less likely to have a straight on, front end impact as in a car.  There isn't very much to hit straight on at a track.  A 5 point is far superior in a rollover/tumble than a 3 point, but only when in combination with a cage and helmet (the HANS does very little for you in this case).

tl;dr: The safety equipment in a car (cage, seat, belts, HANS, helmet) have to all work together to keep the driver safe.  A mismatch in equipment is worse than "worse" equipment.

This topic seems like a tough one to me because there's no extensive data about track safety equipment on the street.  There is plenty of dataless inference drawn by Internet observers, which isn't the same thing.  I shouldn't do the same thing but here I go.

3-points don't do much more than keep you (1) in the car instead of out the window and (2) lined up more or less in position to meet the airbag kinda square-on and stay lined up to the containment cell made by the seat and the lower dash panel.  The belts stretch something like 2-4 inches in a hard crash and supposedly break in a 60 mph collision with an immovable object. 

I don't use a 4-point in a street car with interior, but if I did, I would use a Schroth ASM unit and I wouldn't worry about a submarine.  It's designed to let the torso flip forward a bit so it folds over the lap belt instead of sliding through. And in a street car it's the lower dash panel design that keeps your legs from going downward, not the lap belt. 

If I buy into the wisdom I must always have a 5th strap, then really I must buy into the theory that I must also have a 6th strap lest I get my junk overloaded.  Guy's gotta have his priorities.

Simpson has some published material out discussing a panel of auto passenger safety experts at some industry conference agreeing that the whole no-harness-without-a-roll-cage thing was Internet wisdom too. 

IIRC they said a rollover accident tosses the body around at 30-something Gs.  Their point being, if the roof gets crushed in enough to eliminate the gap, you're going to pound the crap out of your head and neck on the roof with a 3-point too, not "lean over" or be saved by the breaking of your flip-back seat, and a helmet is just going to add weight/momentum and spin your neck worse than it would with a harness. 

They and Simpson advocated getting a stout harness bar, seat with proper holes, and a well-aligned 6-point harness for an HPDE car over just sticking to 3 point belts because the owner doesn't want to put in a roll bar.  They were even opposed to putting a roll bar in a street-driven HPDE car at all because inevitably somebody won't be belted in tight enough on the street and their unhelmeted head will smack a roll bar tube.

I like the HANS concept and I wear a Simpson Hybrid now, but it only protects against one fairly narrow angle of force at relatively higher speeds and a seat halo is what does most of the work at any other angle. 

Plus I have to worry about fire.  Or driving only automatics in the future because I didn't have a window net and my arm flew out.  Or getting fatally speared by a tree spar that pokes into the car between the cage bars (happened at Carolina Motorsports Park once that I know of).

Further research indicates that the Schroth video I was referring to is in reference to the ASM anti-submarining system.

https://www.youtube.com/watch?v=8nsg_ze-CG8