gkmccready

My race shop is recommending I go with a FIA certified seat (Recaro SPG HANS XL, or Racetech) and skip on the back brace. Then in 5 years when the FIA cert expires either get a new seat, or add a back brace. They feel that running without the back brace is a much safer alternative. I think I saw a thread here a while back suggesting that a back brace be used even with the FIA seats. The other thing these guys are saying is that the aluminum seats just aren't safe enough because unless you go to something high end -- they're just plain too thin and deform too easily.

Thoughts?

RedLS1GTO

What are you using the car for? Wheel to wheel? TT? Track days? What are the other variables so far as cage vs. harness bar, etc.

Falcon

Why would back braces not be a good idea, FIA or not?

gkmccready

It's my '87 RX7 and is a wheel-to-wheel car. Full cage, etc, etc. This site has a lot of car builders so I was just curious... my C6 is stuck with stock seats and a harness bar... for now...

gkmccready

The energy from an impact is transferred to the driver rather than having the seat deform/bend and absorb some of the energy?

ssdeuce

I like this seat back brace because it gives you more area to absorb any kind of impact. http://www.bkauto.com/corvette/seat_...t_corvette.php Lots of Saturday night stock car racers use Kirkey and Ultra shield aluminum seats. I’ve heard of them bending in a hard impact but never seen one. One of the beast seats on the market is aluminum and custom for your size that maybe something to look into. http://www.thejoieofseating.com

AU N EGL

ButlerBuilt aluminum seats.

http://www.butlerbuilt.net/products_construction.html

Aluminum Seat Manufacturer Forging Ahead as a Leader in Safety
http://www.butlerbuilt.net/09_Storie...e_crashes.html

Mike Skinner


"All of these crashes exhibited multidirectional, high-G multiple impacts that come with 180mph-plus racing and produced zero injuries.”

In May, Mike Skinner had a brutal crash during the NASCAR Camping World Series race at Lowe’s Motor Speedway (NC). Skinner’s truck went head-on into the wall. The horrific impact lifted the truck into the air and sent it sliding on its roof. Amazingly, Skinner climbed from his truck unscathed, crediting the great safety of his race-truck and his ButlerBuilt seat.

“That kind of impact a few years ago would have sent you off there in a helicopter with your head taped to a board," said Skinner in an interview after the race.

“Big thanks to ButlerBuilt for keeping up with the seat technology to keep us drivers safe in a race,” said Skinner, days after his crash. “They always work with us direct to customize our seats.'

'The 'experts' had predicted the demise of aluminum seats when referring to state-of-the-art seating systems used in superspeedway racing. There was an assertion that aluminum seats cannot withstand multiple impacts without producing potential injury. ButlerBuilt has again and again proven these claims to be reckless and misleading.

“With new SFI seat specifications to be applied in the near future, ButlerBuilt has already surpassed the testing standards with a safety factor of over 400%, as compared to much heavier and tremendously more expensive composite designs. "

gkmccready

Guys, I'm not arguing that the highend aluminum seats aren't super wonderful. But the question was how people felt about using FIA certified CF or fibreglass seats without a seat back brace. Specific experiences with the Racetech or Recaro seats would be appreciated.

trackboss

I would not suggest any seat without a back brace unless somehow the rules are re-written and seats are built to anchor the shoulder harnesses and here's why: Without a seat back brace the seat will move independantly of the upper shoulder harnesses that are solidly mounted to the roll cage structure. It is likely that the driver's shoulders could slip under the harnesses in a crash. One can never predict how severe of a crash may happen if it does. Any builder that suggests what yours did really needs to look into this. Just because FIA has the rule does not mean it is very safe.
If you do choose aluminum seat you really should avoid any of the cheap seats. They truly are flimsy.
The cushioning of the composite seats is nice, but the idea is to come away alive and deal with any injuries in the most severe of crashes. Cushioning may transmit less harm to the driver in very minor crashes, but in an extreme case its best to have a super stout seat along with harness/safety setup and deal with the injuries yet avoid any permanent ones or worse.
I'd bet money that if any of the drivers in the cup cars had bottom mounted seats with no back brace and super long shoulders harnesses (as are fia legal in the porsche GT3 cup cars) while in those crazy barrel rolling, hard impacting crashes, they would not walk away. I've sat in comopsite seats that deflect a whole lot just by me getting into them.
That all being said, race tech is the only composite seat that has provisions for seat back braces in some or maybe even all of their models. Certainly their best seat comes with one and is recommended to be installed as such.
FWIW, kirkey full containment seats are very reasonably priced and extremely safe. If you can fit one in your car it would be something to consider. The high end racetechs are very nice as well, but come with a big price tag.

fatbillybob

I agree with your shop. FIA seats are tested w/o a BB. So that is the only datapoint. For Clubs mandating BB on plastic seats I do not think there is any data to show that is a good idea but I beleive the idea comes from BB on metal seats. Your shop is being smart for follwoing FIA recs on a new seat and SCCA like clubracing rules on old seats, and manufactuers recs on metal seats. Metal seats deform and maintain the deformed shape. Even the best metal seats will do this. Even on my custom made nascar style head cage ultrashield roadrace super seat the company says mount them to the cage at 6 -8 places with back support. They recommend this because metal seats bend. A kirkey unsupported can be the worst seat on the planet. A kirkey with proper support can be better than a FIA carbon $2000 seat. All safety is a compromise. The best seat is mounted to the cage not the car. If you mount to the floor then using a BB is a compromise to gain extra seat support assuming nothing buckles. Plastic FIA seats are not tested with BB and no one knows what happens when your plastic seat bounces off the BB in a crash and where the energy goes and where you go. Those who mount the BB to the back of the FIA seat are also doing untested things because no one knows if the integrety of the seat will be maintained. An exception to this is the Viper and its cousin 4009hr seat IIRC from racetech. These seats have a molded back brace attachment point as part of the seat. OMP, Sparco etc do no have this. the racetech seat is designed for mounted BB and the seats are safer when a BB is used. Surface area of the BB is also untested and just a guess by different makers of such devices. I hate the idea of a pole at the back of my spine personally but there are clever ways to design a good BB to avoid that. The reason for a BB is to maintain the position of the seat so that your belts stay tight. Once your belts become loose you have lost the safety system because racecars don't have airbags. All I posted above is from my memory looking at different seats several years ago. Hope that helps.

kentz06

I have FIA approved Recaro Pole Position seats in my car with correctly installed 6-point harnesses but no bracing. There is a small amount of wiggle in the system, though I never notice it while driving. It would be possible in a hard rear impact for the body to flex the seat backwards and produce some slack in the harness. There might be an increased chance of the harness slipping out of position relative to the HANS device.

Fortunately I have not had a chance to test the system in 70+ track days.

Interesting thread as I have thought about adding bracing for the safety factor...

Dean

JaGsC5

Simple, Buy the best seat you can afford and whether the seat requires it or not, install a back brace. The extremely small cost of parts and labor that it takes to install a brace is minor in comparison to what you would pay if you were injured.

No matter how you look at it, the racing hobby is expensive. A $100.00 is nothing if it helps you return home to your friends and family.

gkmccready

The cost of the brace isn't the issue; it's hearing the guy I trust building my cage tell me that he feels a FIA seat -without- a back brace is the safest set up...

fatbillybob

He is right because 99% chance you are bolting seat to the floor. Ask him what he would do if instead you also made an integral seat framework welded to your cage. Then I bet it would be metal seat bolted to the cage and seat frame ala NASCAR. At this time NASCAR is the leader in racecar safety for "tintop" cars. Open wheel and its F1. Look at what NASCAR is doing and how much the NASCAR seat looks like an F1 monocoque built inside a tintop car. Full containment seats, sidenets, and HANS control body movement much like the F1 monocoque.

JaGsC5

Yeah, understand where you are at. I have been there with other issues myself. My guess is that you obviously have some doubt about your shops opinion or you would not have asks the question.

First why doesn't a composite FIA seat need a brace? Simply, when new, it is strong enough not to flex backward during an impact.

The very same FIA seat that is 5 years old is REQUIRED to have a brace because the structural integrity of the seat is not a strong as a new one and will flex backward during an impact.

You can buy a brand new seat that is 5 years old and you will need to put a brace on it even though it was never installed in a car.

So that in itself should tell you what the FIA is concern with. They don't want you and your seat to move.

So if the concern is the movement of the seat. Why not make an already strong seat stronger?

There was a comment above that stated putting a brace on a FIA seat is untested territory and the integrity of the seat might not be maintained. Not to offend BillyBob but this is not true. If a 5 year old seat is required to have a brace to maintain its integrity in a crash then a new FIA seat with a brace would not be compromising safety or somehow be in untested territory.

Are you safe with a FIA composite seat without a brace? Yes. But each lap that passes and each day that goes by; your seat is getting weaker and weaker from the fatigue of use and age.

I think if you get onto some SCCA or NASA club or pro racing sites and forums you will see similar information.

AU N EGL

I sure hope your seat is not bolted to the floor. But bolted to some part of the cars frame, or roll bar components cross bars / braces under the seat.

gkmccready

More just looking for opinions. I'm curious what DRM, Phoenix, LGM or BlackDog do when they're building cars, honestly.

0Randy@DRM

We always leave the seat up to the customer. The last car that we built had a LaJoy aluminum. I fell in love with the seat, super strong mounting, strong and tight fitting. A bit too tight, but that is what happens when you get married

We have installed just about everything out there. Find the seat that fits you the best and buy it. Then mount it well or kiss your butt goodbye.

Randy

fatbillybob

99% of seats in c5/C6 are bolted to the factory floor bolts on sliders or fixed rails.

fatbillybob

You should always question what I say! Two asprin are good 4 is better is not always true. You see if you have a new FIA seat tested by FIA for like 25g's in their sled that is what works period. When you bolt to the back of the seat with a BB or when you lay a BB anywhere on the seat and the seat hits that unreinforced area of the BB who tested that particular point to take that unknown impact? You could crack your seat or assist your seat in failure by drawing the conclusion that if a BB is good for an old seat it is good for a new seat. FIA would tell you to buy a new seat. The idea of the BB to support the seat first came because we knew metal seats bent. Then someone got the idea that we should BB plastic seats too. There is not a single sled test of such an arrangement to my knowledge. The idea of a BB only sounds like a good idea. I'm in the SCCA. SCCA says new FIA seat no BB. Old FIA seat must have a BB. SCCA is not perfect. In another vette forum thread we were discussing how SCCA allows unsupported nascar bars. SCCA trys really hard to be up to date and well intentioned but really SCCA is just a bunch of guys like us voting on decisions through its CRB. The CRB may or may not have all the data it needs or know how to evaluate the data. They are not scientists. IIRC At SCCA HANS is still not mandated in fact and we all know the value of HANS.