What I have-
Miata,
sparco evo 2 seat, mounted more or less to the floor
3/4 cage with lateral bar 4" behind my seat. Also has bosses to bolt belts to
G Force 6 point, bolt in at all points

PROBLEM-

The sub belts are super uncomfortable. I'm also not convinced that in a crash, they will be any more safe for my nuts, than a 5 point. They are super uncomfortable. The way they fit me from the T bar down through the seat, just sucks. I have tried mounting them wide and narrow on the floor. Not much difference since you are limited to the seat opening anyway. But the T Bar, it's only as wide as the webbing.

I like the sparco fia formula 6 point. The routing of the 6th point looks a whole lot more comfortable. It only comes in a eye bolt style. I have little room for this and already have bosses for bolt in. So now I look at the Sparco gp2/gp3 belt. Same as standard formula, but a bolt in style. Yes!


Talked to OG Racing today. The Guy says "that's not a good belt for a miata, it's meant for a layer back seat position". Ok, that's understandable I gues. What the hell do I know. But then he says " the crotch belts in a Miata are not really to prevent subbing, but to hold the lap belt in place". Ok, now this sounds wrong from what ltitle I know. Am I wrong???

Anyone else have an opinion as to why I should not run the Sparco gp2/gp3 style belt?

The later in life I get, the less trusting I am of some random person giving me advice.

 

Schroth Profi II-6H. The sub belts are stitched back on themselves so they ride against your inner thighs instead of directly on your man-bits.

 

HANS is an absolute must with this harness if I recall correctly.

 

HANS is an absolute must with any harness, IMO.

 

Every belt manufacturer says not to use formula seat belts in an upright seating position (read: normal GT-style) race seat, so I think that's pretty good advice to listen to.

When you crash wearing 4-points, the shoulder belts pull the lap belt up over your abdomen. An important role of sub straps is to resist this movement. I hate wearing 6-points on the street, and a clever aspect of an OEM 3-point is that the buckle allows tension on the shoulder belt to pull the lap belt tighter. I feel confident that my sub straps are unlikely to crush me in an accident, but they are a bit uncomfortable in normal clothes. On the track, the thickness of a race suit eliminates this annoyance for me.

 

Schroth also has the Hybrid, but the lap belt pull options are limited.

 

Right, that's why I currently use a 6 point. The thing is, if you don't have a vagina, and you slam head on with something, your nuts are going to disintegrate. At the least, they will be crushed.

Although I will have a HANS, what is the difference between a Hans specific belt, and my G Force 6 point?

 

It's not the HANS-specific bit. All Schroth Profi belts (even the non-HANS-specific variants) have folded sub straps to offer more "clearance."

 

HANS-specific belts have 2-inch straps over the HANS, then widen to 3" for the adjusters.

 

schroth profi 2-H user here with good results. 2x more expensive than the g-force I was using but worth every penny for the extra comfort and superior lap belt adjust ability.

 

Cost is not too much of a concern, when we are talking seat belts. IMO.

 

You'd think so but really they shouldn't.

My 6pt Schroth clubman is not comfortable in the crotch either but your lap belt should prevent you from sliding forward in a crash so you should get any further into your sub belt then when your strapped in tight.

I've had a tire wall stop me from 45mph with no sore parts the next day, tight lap and shoulder belts are critical (obv with a HANS)

 

As this thread nears a quick consensus and closure, I take away this:

2 inch lap belts are great (says Schroth )
3 inch shoulder belts are not compatible with a HANS device
T bar 6 points are good for some, uncomfortable for others
A hybrid 6 point is similar to a GP type crotch belt, but works with a GT seat(upright shell type seat) with single crotch belt opening.

A GP type 6 point is specifically for a GP seat, which has totally different crotch belt cutouts
A GP shoulder harness mount is not a standard bolt in, it uses a cross bolt in double shear

This is my takeaway. ...

I test textile products for a living. For a number of reasons I think that Polyester is a better material for a seat belt. Schroth is one of the few who use Polyester.

A Hybrid is good. Fits HANS, uses a 2" lap belt and is comfortable.

Still not totally understanding why a GP style couldn't just be mounted in a GT floor mount if I have the double shear upper....

 

The 2 inch lap belts really are great -- you can easily feel the difference in how tight you can get them.

3-inch shoulder belts ARE compatible with HANS devices. The 2/3 HANS-specific belts are just more comfortable than the straight 3" with an HNRS, but cannot be used without one.

 

Explain this further.

My take was that the 2-3 belt just didn't provide as good of load spread as the 3" belt, when not wearing a HANS. But for that matter, all factory belts are 2" so....... the necessity isn't crystal clear.

 

2/3 is more comfortable because it doesn't "spill over" the HNRS belt guides and possibly chafe.

The reason I say that the 2/3 belts must be used with a HNRS is that it is stated as a restriction by the belt manufacturers. Presumably it has to do with reduced load spread, but all my responses are just directly based off the belt makers' documentation. I like to follow their rules.

 

That's the problem. All of the manufacturers vary in their description of proper use. I do like what schroth has to say. Ilikeitalot.

 

Will you be at MRLS? You can sit in my Schroth Enduro belts if you're there.

- Ridiculously nice adjuster hardware that never interferes with the seat
- Folded sub straps (what Andrew brought up) are really nice and much more comfortable than G-Force non-folded straps

 

Are you running the seat cushion that came with a recently made Sparco? If so, it looks like this:

I have a Schroth profi-II 6H and this cushion ruins the awesome sub straps that avoid crunching your nuts when you seriously tug down on the lap belts. It essentially makes both sub straps run right into your crotch. Terrible design for 6 points. I don't run the bottom cushion.

The sub hole in the seat is much wider and allows the straps to separate and be more comfortable. I'm waiting for Sparco to sell 2 models of their more popular seats, one for a 5 point belt, another with separate holes and a special cushion that allows the sub belts to be spaced apart. It probably won't happen, but if it did, I would pay a little more for that feature.

 

I run the cushion, yes, I have no ***. It's a must. But I cut it up with a bread knife, to alow maximum ball space. I cut it like 4 inches each direction. I was completely surprised that they dont make a better one.
I sew stuff all the time at work, but was so pissed off before an autocross, that I had no choice but to start stabbing seat guts.