JCP911S

I suspect that what he HANS did was stop head rotation.... even in a dead square side hit, I would expect the head to want to rotate around the neck as well as go sideways... especially wiht a helmet on, my guess would be that there is enough mass in the front of the face to cause this.

this would tend to limit total side to side movement of the head as well as significantly restrict twisting.... which I would think is a bigger risk as far as neck injury..... even so, a head restraint seat is probably a good idea.

That said, the seat also needs more shoulder support... as pointed out in other threads, the body needs to be supported at the hips, shoulders and head to keep everything in alignment.... support at the ribs is probably not ideal... they are fragile.... if the hips and shoulders is aligned... the rest of the body should be too.

RedlineMan

Hey G;That's exactly how I felt when I read Bill's note. HANS = Good... even from the side hit. More fuel for my HANS fire.

JCP;Exactly what I have been gathering from my reading. The early onset of tension in the belts is key, and what the new Simpson (or similar) sub-setup offers.

My reading indicates that two things happen when you hit the belts. 1st, the legs pull forward and the hips rotate under the lap belt. How much is dependant on the type of sub and how low the lap belt is held. 2nd, the torso hits the shoulder belts creating some compression, and this also follows the hips rotation forward to allow the body to continue to move downward and to some extent under the lap belt.

What I gather the advantage of the Simpson Platinum Series to be is that it stops the hip rotation MUCH earlier in the event, and therefore the torso from moving downward, and thus tensions the whole belt system much earlier than without a 6-point "cradle" style sub. This quicker full retention of the body and loading of the belts REDUCES the KE whip that snaps body parts forward.

Interesting!

I myself have learned a lot from our continued discussions, and my understanding continues to evolve. The more we ask, the more we search. The more we search, the more we learn. Thanks, all!

924RACR

The crash videos that I've seen from pure lateral impacts, along with the data (this all presented at the previously mentioned Tom Gideon presentation) shows that the HANS does not show any improvement in the pure, 90-deg lateral hit (over unrestrained head). This from Tom Gideon, who is a proponent of the HANS device! The strap might have been stretched during a subsequent (rebound) portion of the impact, and I'd hesitate long and hard before coming to any conclusions that say it helped, in spite of lab test results (Delphi and Wayne State impact sleds). Straight up, according to him, the HANS device does nothing at all outside of a 45deg angle of impact.

Again from the presentation, I'd re-emphasize that the side impact net is stronger and capable of handling higher loads than most if not all of the seats tested, not to mention it's effectiveness at any angle of attack off of straight-ahead (whereas seats, even if they're strong enough, which most are not, face reduced effectiveness). Not to say you shouldn't get or build a good seat, but back it up with a net. You'd be amazed how these cantilevered seat sides can bend out of the way when not properly supported.

M758

I am planning on side net in my 944-spec car.

I currently have sparco pro 2000 seat that I was going to replace with head restraint type. The side NET seems to be much more effective AND cheaper. I can't argue with that so I will install that and keep my pro 2000.

My only concern is how to mount the side net. I have seen Vaughan's Pics, but don't know how I will be able to secure it from side loads on my cage. I am thinking that I will need to have some one weld on attachments to make this happen. I really need to buy the net and get in there to see it for myself on my cage in my car.

I am still torn on the HANS vs ISAAC issue. I do still prefer FIA composite seats.

No one has yet to answer what "Standard" are the Aluminum seats rated to?

In my view for the money....

There are Cheap Al seats then the Basic FIA composites. At the bottom level I know what the FIA seats are good for, but not the Al seats.


At the high end the Racetech Viper Comp Coupe seats are soild and seem quite good, but cost similar to the top FIA composite seats. So therefore the money is all about the same and we can ague about which one is more comfortabe, safer, etc.

SO Could the CHEAP (Sub $300 or Sub $500) ALUMINUM SEATS MEET FIA TEST STANDARDS?

924RACR

I doubt the sub-$200 seats could meet FIA standards, you're quite right. The price threshold might be as high as $500 or so. That's part of why I feel a need to upgrade my own seat.

As far as mounting the net in your car, you're correct, there's a need for lateral restraint of the net; the pics shown on my website do not show a completed installation, only the beginnings of one. I still need to do plenty of work to match it up and secure it completely. I suggest when you do order it to talk to Wes (at BSR) or even anyone else to request details on how best to secure it laterally; the feedback I got from Wes was to add loops of 1/2" round stock, shaped like a handle, welded onto the bars of the cage, just like some use to locate their shoulder harnesses laterally on the main hoop. He commented that hose clamps etc could also be used, but I'd be seriously concerned with that approach, naturally.

M758

Well that is my point.

So should we really be spending in the $500 range for a seat. There some that cheaper (mainly Al Seats), but are these worth the money or not. I hate to spend more money on safety that really is not any safer. Heck I may have done this on my Schroth harness $300 vs $109 FIA G-Force so I'd hate to do it on seat too.

That is why the Aluminum seats are temping, but that little voice inside my head says go with FIA composite. They are FIA certed and the "standard" of world wideroad racing. Al seat are for the "redneck" roundy round folks.

Well this discussion as well as a few other on this forum lead me to believe there are at least SOME good high quality Al seats are NOT just for Cheap AS* rednecks. Cleary some work quite well (arguable some even better), but were is the cut off? From price point I'd except two $800 seats to do pretty well in crash, be light and comfortable not mater what they are made of.

Not so clear...

Geo

DOH! You're RIGHT. I was speculating. Thanks for straightening me out.

robmug

A cheap FIA seat and an expensive FIA seat both meet the same criteria. All the extra money gets you is, in some cases, a more expensive material (such as carbon fibre) and, in the case of cobra seats, more expensive foam (such as Confor & comfortemp) which actually behave differently to other foams.

Summary - all FIA seats pass the test, no matter how cheap or expensive they are.

fatbillybob

"I currently have sparco pro 2000 seat that I was going to replace with head restraint type. The side NET seems to be much more effective AND cheaper. "

Yes but what about impacts on the driver's side. Is the window net enough or intended to do what a full containment seat can do?


My only concern is how to mount the side net. I have seen Vaughan's Pics, but don't know how I will be able to secure it from side loads on my cage.

Same problem...and I still have not seen any pictures of a correct mount of sucha a net.


As to the poyester vs nylon belt. the issue is also relative streatch as well as KE start-up . Less sretch seems to be better. Thus you don't bang around in your seat as now you have loose belts after the initial streatch and when yo come away from the seat your body compresses more and gets all out of shape causing injury. Polyester belts keep your body position more as intended. BTW the only one I know doing the poly is the platinums and scroth.

Rich Sandor

Does anyone know if Porsche's Recaro "sport seats" from the mid 90's or even the one that come in today's GT3's are FIA cert?

Dave E

What about if the seat "stretches" or bend out of the way like Bill's did, and then your head is caught by the net and your torso keeps going? This seems like a recipe for a broken neck. Are there specific guidelines used to determine the height and distance from the side of the seat to mount the net? Would it be feasable (or advisable) to catch the sideways movement of the seat with the net? Do sliders negate the FIA certification? the Sparco sliders under my seat seem well made, but convinience at the expense of safety is no bargain.

924RACR

That's why the net is intended to be mounted to catch the shoulder as well as the helmet. And yes, the intent, if the seat has side supports of any sort, the net will provide a backup to the seat; actually, it's far more effective than the seat, handles much higher loads, and when used with a good seat (which can help spread loads to the body if properly designed), it is extremely effective in supporting the body and protecting against injury.

Important words to emphasize here, but it really is that dramatic: protect against injury! The net is that effective.

robmug

The mid 90s had a different FIA standard, so even if they were, it would not be as tough. The previous FIA standard was a static test (a load was applied to the seat gradually, until it broke; this didn't place any strain in the mount points...) Then you have the age of the composite...

Not sure about current GT3 shells - if they are, they will have a sticker midway up one of the sides. My guess is that it's not FIA certified, but has probably been tested to that standard by Recaro.

Then again, the GT3 must have gone through the European crash test regulations for seats, where the seat must be homologated in the car.

Geo

It's my understanding that the Sparco sliders are FIA approved.

M758

With respect to the driver's side window net.

Yes I would expect that to prevent too much head movement in that direction. I know that mine is mounted so that it is very close to my head. In fact I believe it brushes the shoulder bolster on my seat.


Rob... Understand that all FIA seat meet the FIA Standard no matter the price. What I DON'T know is if any EXCEED the standard and by how much. Of course the FIA testing was not designed to determine this, but does provide a minimum.

My point on Al seats is that it appears SOME meet and can exceed the FIA standard. I am not certain however on the other lower budget ones. Cleary from the responses here nobody else know about and minimum standards Al seats must meet.

Great discussion. Guys!