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Author Topic: SCCA rule proposal to require seat back braces - even for FIA seats
dtfastbear Verified Driver Made Donation to Website
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Looks like there is a rules change going to the board for approval to require seat back braces for FIA approved seats. WTF??

Please help me in my campaign to stop this. I feel strongly that this is a terrible idea. I've included below the text of the letter I wrote. If you agree with the reasoning, please write your own letter, too.

Cheers,

Dean


http://www.scca.org/documents/Fastrack/10/10-fastrack-june-club.pdf

SUGGESTED RULES FOR NEXT YEAR

The following subjects will be referred to the Board of Directors for approval. Address

all comments, both for and against, to the Club Racing Board. It is the BoD’s policy to

withhold voting on a rules change until there has been input from the membership on

the presented rules. Member input is suggested and encouraged. Please send your

comments via the form at http://www.crbscca.com/

gcr

2. #855 (CRB) Mandatory seat back braces for all seats

In 9.3.41, delete: “Seats homologated to and mounted in accordance with FIA standard 8855-1999 or FIA Standard 8862-2009 or higher need not have the seat back attached to the roll structure. The homologation labels must be visible.” [The CRB has been made aware of deficiencies in mounting of FIA homologated seats that would be mitigated by the additionof a seat back brace.]

----------------------

My letter:

I noticed in the latest Fastrak that there is a proposed rule for requiring seat back braces for ALL seats, including FIA approved seats.

I am strongly opposed to requiring seat back braces for FIA approved seats. The FIA seat homologation and testing is not performed with back braces in place, so therefore there is NO TESTING DATA to show that these seats are safer (or even safe) with a back brace in place. FIA testing methods are performed on a "free" seat that is either side or bottom mounted, as recommended by the manufacturer. The seats are therefore free to flex and absorb energy as they flex on their mountings. To mandate that seats be installed in a manner inconsistent with the manufacturer's recommendation and certification testing is not a move towards improved safety.

Crash safety testing often shows that what *really* happens in a crash is often surprising and quite different from what one might expect to happen by just eye-balling a design. Making the assumption that back braces will increase the safety of an FIA seat without test data to prove it is inappropriate in my opinon.

Thanks for your consideration.

Dean Thomas

--------------------
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d mathias Verified Driver Made Donation to Website
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"Oww, that was my spine dude!"

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I'll try to get around to a letter this weekend. It's a really bad idea to require a back brace on FIA seats for 2 fundamental reasons:

1) It can significantly redistribute and potentially cause significant increases to resulting loads on various parts of the human body.

2) It will significantly change the load paths through the seat and can compromise the overall structural integrity.

Testing is the only way to know if a change like that will improve or decrease the occupant safety.

--------------------
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Uhmm... seat back braces will VOID the FIA rating on composite seats...

Zauskycop Verified Driver
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I smell a lawsuit on the first "seat related" injury involving an FIA seat, and an imposed back brace.

--------------------
Tracy Ramsey
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Letter sent.

B Wilson Verified Driver Series Champ
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FYI, It's my understanding that form letters are sometimes disregarded by the CRB/BOD, so make sure and give your letter a personal touch if you choose to copy Dean's letter.

-Bruce

--------------------
Bruce Wilson
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dtfastbear Verified Driver Made Donation to Website
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Very good point, Bruce!

Make sure you let them know why YOU are for/against the change.

BTW - if anyone wants to include a link to the FIA testing standards (as I forgot to), here they are:

http://argent.fia.com/web/fia-public.nsf/6CC535...FILE/Competition_seat.pdf

You might point them to section 1.1 and 1.2 the very first sentences, that say all testing is to be performed only with mounting as foreseen by the manufacturer...

Cheers,

Dean

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Connie 62 Verified Driver Made Donation to Website
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Did the SCCA get approval from FIA to mandate this change? A seat back brace is not a solution for an improperly installed FIA seat. Properly installing the seat is the solution.

--------------------
Jim Thill
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I have FIA seats in my cars and can't wait to hear the argument for seat braces on a plastic seat that was not designed not to use them. Has there been a problem in the past? I certainly want the safest installation as possible but I think we would need specific guidance from the seat manufacture before we start drilling.

--------------------
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dtfastbear Verified Driver Made Donation to Website
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Jim and Jamie - I hope you guys are writing letters to make those points!! [Smile] [Smile]

Unless we convince the board otherwise now, you won't get an argument for it, you'll just get a rule that says you have to do it...

NASA has this rule for FIA seats more than 5 years old, which I don't like but can appreciate, since the FIA rating IS only good for 5 years. I spend the money to get a new seat every 5. No way, no how I'm drilling holes in my brand new $1900 Recaro to make it into an untested contraption.

Dean

(edited for grammar)

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Chris Haldeman
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quote:
Originally posted by Connie 62:
Did the SCCA get approval from FIA to mandate this change? A seat back brace is not a solution for an improperly installed FIA seat. Properly installing the seat is the solution.

+1

mtm68 Verified Driver
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letter sent....
on improvedtouring.com, there is a great letter Greg Amy wrote in 01 on this topic as well.

--------------------
-
Marcus Miller
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kevin 22 Verified Driver
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I have a FIA Race tech and would not drive without the seat back brace.

At the time I wanted to install it read all about how I would do more harm by installing it so I contacted Racetech themselves and this is the answer I received.
Notice the President of racetech said in his response he also says He would not drive without the seat back brace.

Kevin, Your 4009 seat does not need a back brace. Our crash testing shows that you can increase the seat and driver survivability by adding a back brace. The standard 4009 is a FIA 20G tested spec. Our back mounted Viper seat is a 45G tested seat. The 45G test was gained by back mounting the seat. Your sanctioning body should have a rule on this. Racetech does have a retrofit kit that can be installed correctly to gain the back mounting system. The kit includes high tensile attachment plates the must be mounted inside the back of the seat. We do not recommend using any other attachment system. The plates are similar to the ones we use for the lower bracket attachment points. I personally will not drive a race car without a back mounted head restraint seat. I hope this helps this confusing situation.
Please feel free to contact us if you have any other questions. Regards.
Pete Morley. President

--------------------
Kevin Anderson

Sean Allen Verified Driver Made Donation to Website
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Yes, but that is NOT a simple back brace install. That involves mounting backing plates within the seat etc. etc.

Brian Ghidinelli Verified Driver
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Kevin - your situation does not sound like a 'seat back brace' but rather an integrated-to-the-seat mounting system for mounting to the back of the seat. I can see how back mounting the seat would be as effective as bottom or side mounting but a seat back brace in conjunction with side/bottom mounts is not the same thing.

I'm writing my letter...

--------------------
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I will just call OMP and see if my seat is going to be safer if I install a seat brace. If it is then I will install the seat brace with or without a rule change; if its not then I won't.

--------------------
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Juan Pineda Verified Driver Made Donation to Website
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What is the schedule for a decision? The timing is really bad for me, as my seat expires in June, so I was in the process of ordering a replacement. This obviously throws a monkey wrench into that plan.

-Juan

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TillerTech
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Juan,

Does the GCR require FIA seats to be up to date?
You might not have to replace it.

J

--------------------
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Juan Pineda Verified Driver Made Donation to Website
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quote:
Originally posted by TillerTech:
Does the GCR require FIA seats to be up to date? You might not have to replace it.

Unfortunately, yes.

-Juan

--------------------
www.ArtOfRoadRacing.com Race Craft Clinic - Thunderhill - 30 Jan 2011

TillerTech
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must have been a change lately, wasn't a few years ago.

J

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Keith in WA Verified Driver Made Donation to Website
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The GCR says that if the seat is homologated and mounted to the standard, it doesn't need a back brace. The FIA standard gives a service life to a homologated seat so beyond that it isn't homologated any more.

The info from Racetech applies only to their seat and hardware. It's a far cry from drilling a couple holes in any seat and bolting on an I/O Port back brace. It's tested with known equipment and known results.

I've been mulling this over for much of the afternoon. Does anyone have any advice for how much detail to put in my letter? This is right up my alley from a professional expertise standpoint but a technical paper wouln't be appropriate. Provide some key points and offer to provide more information if requested? If there are people on the board who have a background in the subjects involved, I'd be more than happy to pick up the phone and discuss. I can't share anything proprietary but there is a lot that is general knowledge if you're close to the subject.

--------------------
Keith Novak
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1. FIA 8862-2009 standards will be hard to meet without a back brace.
2. The floor structures of most production cars are not strong enough to resist the torsional loads generated by a seat mounted solely to the floor. The seat creates quite a lever with the mass of the torso under G loads. There is experience with this issue.

--------------------
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dtfastbear Verified Driver Made Donation to Website
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When the seats are designed for and tested with backbraces, then this will be a great idea. Sounds like Kevin's seat is, and the manufacturer provides a kit specifically designed and TESTED for that seat.

I still have yet to see any test data or results that show that *any* legal backbrace installed with *every* FIA approved seat is safer than a properly mounted FIA seat sans brace. But that is what the rule, as written, will result in.

I'm happy with the rule as written that allows for using back braces with any seat, so that Kevin can run his setup. But I haven't seen data that suggests let alone proves that my brand new Recaro Hans seat would be safer with two holes in it and an IO-Port brace on the back of it.

I'd also be all for additional rules or guidelines for seat installation that address the problems mentioned. I just don't believe this blanket rule is the right solution.

Cheers,

Dean

--------------------
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Kent Carter Verified Driver Made Donation to Website
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quote:
Originally posted by dtfastbear:
When the seats are designed for and tested with backbraces, then this will be a great idea. Sounds like Kevin's seat is, and the manufacturer provides a kit specifically designed and TESTED for that seat.

I still have yet to see any test data or results that show that *any* legal backbrace installed with *every* FIA approved seat is safer than a properly mounted FIA seat sans brace. But that is what the rule, as written, will result in.

I'm happy with the rule as written that allows for using back braces with any seat, so that Kevin can run his setup. But I haven't seen data that suggests let alone proves that my brand new Recaro Hans seat would be safer with two holes in it and an IO-Port brace on the back of it.

I'd also be all for additional rules or guidelines for seat installation that address the problems mentioned. I just don't believe this blanket rule is the right solution.

Cheers,

Dean

1000% agree

--------------------
Do I turn my 99 Hard S into a killerfast SM or seek a donor?

Keith in WA Verified Driver Made Donation to Website
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Kent,
You and I are both stress guys so we could compare notes. There's obviously more behind your comments than 2 bullets worth of info. There's more behind me disagreeing right now offhand than I could put in 2 bullets too, especially not knowing your reasons. Too much info to bat around in sound bites. Most of it wouldn't be intelligible to people who haven't dealt with both the mechanical and biomechanical sides.

For now, my position stands. If you make a generic, untested change to a whole variety of seats with entirely different designs, all bets are off with regard to the safety of the person sitting in that seat.

--------------------
Keith Novak
(Will work for tires)

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RE: expiration of FIA seats:

quote:
Originally posted by TillerTech:
must have been a change lately, wasn't a few years ago.

To clarify, the expiration date matters if you don't have a back brace. If you do brace it, then they don't care about the date.

-Juan

--------------------
www.ArtOfRoadRacing.com Race Craft Clinic - Thunderhill - 30 Jan 2011

dtfastbear Verified Driver Made Donation to Website
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To clarify Juan's point, the NASA CCR explicitly makes the point that an FIA seat more than 5 years old is no longer "certified" and therefore must have a backbrace.

The SCCA GCR simply says that seats "homologated and mounted in accordance with the FIA standard 8855-1999 or higher [don't need a back brace]" As someone already pointed out, the homologation is only good for 5 years, so technically the SCCA also requires a >5 year old FIA seat have a back brace. I haven't heard a story of the rules being interpreted and enforced in that manner, however.

Cheers,

Dean

--------------------
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TillerTech
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Yes correct, however an extension to the expiration date can be attained. It is very simular to the fuel cell regs.

How does SCCA and NASA deal with non certified seats? The alum ones are not FIA nor SFI recognized. There is no design criteria for strength or padding.

Personally, I would stay with an FIA seat, if it will fit correctly into the car. Seat slider assemblies scare the hell out of me, but allowed.

The 8862-2009 specs are a very good move, it increases rearward/back of seat criteria and increases component life to 10 years.

J

--------------------
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dtfastbear Verified Driver Made Donation to Website
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It's a big hole in the rules, IMHO. I just re-read the SCCA regs. It just says "one piece bucket seat." No requirements beyond that, so the fiberglass bucket out of your late 60's dune buggy will be just fine, as long as it has a back brace, of course!! [Wink]

I tried to get an extension on a Recaro seat once - the Recaro US folks said it would have to be sent back to the factory in Germany.

I'm not in touch with the 8862-2009 specs - when will seats that meet them be coming on the market? Should we expect a big price increase?

Dean

--------------------
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TillerTech
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Yes, correct, must be re-certified by mfg.
Yes, I would imagine the new regs will require much more testing and better construction.

Are there any US made seats that are FIA certified?

The fuel cells are the same, return for inspection and extension.

J

--------------------
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Greg Bush Verified Driver
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I'm going to bet this started as an idea on how to extend the life of FIA seats so we don't have to throw them away, and somewhere the option turned into a must-do for all FIA seats.

Maybe this rule should read that after they expire they need a brace, but not required before?

Then everyone gets to keep doing what they do and the risk takers can take a new one (if you see it that way).

Rules are rules, and safety is personal.

FWIW I think its a bad idea to brace a seat not made for it...

Jonathan Christian Verified Driver
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Back brace is a bad idea. We had a Miata in our region equipped with a back brace that slid sideways into a tire wall. Instead of the seat flexing and returning to its normal state, the back brace bent and tweaked the seat, holding in its awkward position. Luckily the driver was ok, but was taken to the emergency room cause he had back pain.

Brian Cates
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What, let me guess, after the FIA certified seat gets to a pre-determined age the carbon fiber construction is no longer structurally able to resist the impact forces it was originally designed for?

Sounds like an excuse to make everyone buy a new seat.

I can understand seat belts, somewhat, if they are left exposed to the sun, but now seats have a life expectancy?

Unless the sanctioning body rules require an updated and more stringent FIA performance spec, the seat should be good forever.

Adding a back brace is a very bad idea. It will just transmit the forces from a rear end collision right into your spine, no thanks.

As a structural engineer, this back brace concept has not been very well thought out and could potentially cause more serious back injuries.

I'd rather see the rules pay more attention to how the seat is mounted to the floorpan, which is really where a safty problem is likely to occur.

Would you put a band-aid on your neck for a cut on your leg? [Smash]

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I know that I'm being hypocritical by posting this after stating that only testing and data should be considered, not just eye-balling, but...

This is the only brace design that I've seen that makes sense to me. Would love to see some sled runs on it.

http://www.ogracing.com/catalog/2-Car/36-Roll-Bar...MPETITION-SEAT-BACK-BRACE

Other designs seem to concentrate the force too much in a small area right in the middle of the back. Again, this is purely conjecture, not testing or analysis.

I don't think this one is designed to be bolted through the seat - it is meant to be located directly behind the seat to provide support for a rear impact where the belts would go slack instead of holding the seat in place (line a frontal impact).

This wouldn't be legal for the proposed rule, however, as the SCCA requires a brace to be bolted through the seat back for lateral support.

Cheers,

Dean

--------------------
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I would think you would need 2 braces 45* out from each back corner of the seat, or one big one.

The current back brace works for frontal and back impact, but side impact such as what Jonathan mentioned about??

So 45* covers both?
J~

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quote:
Originally posted by Brian Cates:
What, let me guess, after the FIA certified seat gets to a pre-determined age the carbon fiber construction is no longer structurally able to resist the impact forces it was originally designed for?

Sort of true actually. Carbon fiber composites are prone to generating tiny little cracks in the cured resin called microfractures from even pretty minor abuse. Those little cracks can quickly grow into big cracks. 5 years is probably where they figure the seat has seen enough abuse that the material is questionable.

--------------------
Keith Novak
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I contacted Recaro about this issue a few years ago. They put me on the phone with one of their engineers.

I asked specifically if it okay to add a seatback brace to their seat (at the time a Pole Position). He said they are not allowed to recommend or not recommend one, only that their seats are tested and FIA approved without one.

I prodded him several times, but he stuck to his answer. However, by the way he was saying things it was clear to me that if he could make a recommendation, he would say not to add one.

Just my $0.02...

--------------------
Kim

91 BRG SMT RIP
06 MX-5 Cup

"Life's journey is not to arrive at the grave safely in a well preserved body, but rather to skid in sideways, totally worn out, shouting 'Holy sh*t...what a ride!'" - Unknown

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Back when the seat back brace was initiated wasn't the purpose to prevent the driver from winding up in the back seat compartment of a sedan or coupe if the seat mounts failed?

I'm rather large and my Miata seat can go no further back as it rests on the rear transverse bar of my cage. I would have to move the seat forward to install a brace and buy a smaller diameter steering wheel to even drive the car uncomfortably! Have these guys ever even tried to enter and exit one of our cars?

Watching some of the rule changes over the years has convinced me that regardless of what the workplace guru's say, Dumb ideas not only exist but tend to gather momentum!

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Den

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quote:
Originally posted by sirois737:
Back when the seat back brace was initiated wasn't the purpose to prevent the driver from winding up in the back seat compartment of a sedan or coupe if the seat mounts failed?

I'm rather large and my Miata seat can go no further back as it rests on the rear transverse bar of my cage. I would have to move the seat forward to install a brace and buy a smaller diameter steering wheel to even drive the car uncomfortably! Have these guys ever even tried to enter and exit one of our cars?

Watching some of the rule changes over the years has convinced me that regardless of what the workplace guru's say, Dumb ideas not only exist but tend to gather momentum!

A proper back brace serves to increase rigidity in every plane. Attach your seat to the bulkhead and you have the best possible mount.

A half inch of bending at the floor is at least couple of inches movement at your shoulders and it potentially enough to let you out of your harnesses.

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Do I turn my 99 Hard S into a killerfast SM or seek a donor?

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quote:
Originally posted by Kent Carter:
[A half inch of bending at the floor is at least couple of inches movement at your shoulders and it potentially enough to let you out of your harnesses.[/QB]

Hi Kent, I would agree if you were well over 12 feet tall (which you weren't last time we raced), other wise its well under an inch lateral movement. I am questioning your math here, not whether an unsupported seat could move several inches in a sideways impact.

Craig J

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keep in mind, these are the same people that polled all the IT racer's about allowing engine mount's with alternate material's... the vast majority of the driver's were in favor of this.... so what did the board ultimately decide? to do nothing!

hoop

--------------------
hoop
'91 Spec Miata
'90 NA Beater/Track Day car
'06 RSX Type S

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Craig: Each 1 degree of rotation = 1/2 inch of deflection 30 inches away. It adds up quickly. It doesn't take a lot of bending at the mounting points to make a big difference at shoulder level.

The most rigidity isn't always the best answer though. Concrete is more rigid than a trampoline. Which would you rather land on?

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Keith Novak
(Will work for tires)

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Goody, a math debate!

Actually I agree with YOUR math, just not my buddy Kents. I am not sure however why you choose 30". Thats a really, really tall guy.

Anyway back to my original critique, 12mm deflection on a 430mm spacing (approximate width of rails) extended vertically to say 550mm does not translate to over 50mm lateral deflection. Its under 3/4 inch. Whew, I need to go find some TV to watch - must be bored to go online stirring up a math debate....

I defer to your professional training on the issue on seat rigidity. What you say makes sense.

Craig J

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I just use those numbers since that was an actual problem I found at work years ago and they stuck in my head. They're handy for back of the envelope stuff. 30" is ballparkish hips to shoulders too.

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Keith Novak
(Will work for tires)

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Craig,

You are right! I did the calculations on my seat mount and realized that it is the very top of the seat that moves over 2 inches when I moved the front mounting point up or down by 0.5". The top of the shoulder belt hole (which is at 27") moves about 1.7". A few months ago, I reset the position of my seat by 0.5" at the front mount and had to shorten my belts by about 2", which is why I spouted off that number.

I was doing fore-aft movement 'math' instead of lateral. I'm not sure that my belts would loosen in purely lateral movement of the seat.
::: shudder :::

I still hold that the Miata floor is weak enough (without the factory seat mounts) to allow the weight of the driver to bend the floor enough to let the driver out of the belts... at least in fore-aft movement. The forces involved are bigger than most people think.

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Do I turn my 99 Hard S into a killerfast SM or seek a donor?

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Kent, we can't just start agreeing with each other. I think its against forum rules....

I have been thinking a lot this week about the safety issues relating to our seats. As some of you might know, a week ago there was an accident at TMS that claimed the life of a passenger and has the driver (a fellow South African) in critical condition after hitting the wall in a Corvette. My prayers are with both families and my brain is engaged with how we might make our hobby/sport safer. There is no indication that seats were a contributing factor in this accident, safety is simply on my mind and seats are part of that.

Over the last 3 years I have searched the web for good info on safety and have found little other than the occasional educational paper. I have a family member who had the opportunity to test for a Nascar team and who also toured the safety research center that Nascar runs. From his description and the info I have read, it seems that Nascar is the most advanced in the world in data collection of impact versus injury. This research, applied into driver containment design, has resulted in dramatically fewer injuries in Nascar in the last few years.

I wonder why this info does not seem to have trickled down into club racing. As an engineer I am bemused at the degree of guess work which seems to go on with our safety issues. Case in point the suggestion to arbitrarily brace all seats without manufacturer testing or approval. Furthermore the limitations on floor pan bracing and the prevalence of left side roll cage bars immediately next to drivers heads in SM's. When I think about it I get chills, and only feel much better when I wander over and take a look at the safety of the guys driving Formula Vees.

Craig J

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Craig

SCCA/NASA/PCA/PBOC pick your flavor....do not have R&D centers or even engineers on staff to develop safety rules. They depend on SFI or FIA to do the testing and establish the standards. The people who make the rules are not safety professionals....they are just people trying to do the right thing. NASCAR got into this big after they lost their star. This is one of the guys who has done a lot of testing on seats. http://ispseats.com/ Here is another good article http://www.circletrack.com/safety/ctrp_0712_seat_harness_mount/index.html

If you look at most of the seat manufacturers installation instructions they recommend attaching the seat to the cage so the driver and cage move together with an impact. Do you realize what an uproar there would be if SCCA mandated that all seats be mounted to the cage?

--------------------
Paul McLester

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Paul... this back brace proposal is just that. There is no more important connection to the cage, in my opinion, than the ones that occur at at the upper torso/shoulder level as this is where the primary forces are applied and also where significant roll cage structures are universally available in all cars to adequately attach the seats. The relationship between the seat and the cage and belts is obviously of critical importance for the survival of the driver in a wreck. Mounting the seats to the floor alone simply can't be enough.

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I wonder if it would be acceptable to attach the seat to the roll cage more from the sides than directly in the middle. That would provide the aft and lateral support, transmit the forces more into the shoulderblades than the spine and allow the spine area to still flex a bit.
[scratchchin]

--------------------
Keith Novak
(Will work for tires)

 
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