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-   -   Harnesses and seats (https://www.rx7club.com/race-car-tech-103/harnesses-seats-786153/)

wvumtnbkr 09-11-08 08:09 AM

Harnesses and seats
 
Is it possible to run a harness with the stock s4 TII seats? Is it safe?

If not, what seats do people who road race run?

Thanks!

wrankin 09-11-08 09:10 AM

Well, that's a big question to answer, there are many facets.

0) By harness, I assume that you are talking about a full 5/6/7 point rig with a sub belt(s).

1) Stock seats are not really designed for proper harness use, and they certainly aren't designed for proper road racing (ie door-to-door). A proper race seat is a 1-piece shell design, either in aluminum, fiberglass, carbon fiber, etc. They do not recline. If it reclines, it is not a racing seat.

http://www.kirkeyracing.com/
http://www.racing-seats-usa.com/sparracseat.html

2) I seem to recall that the TII seats have a separate headrest, so you should be able to run the shoulder belts between the headrest and the seat. You can use a 6-point harness and anchor the sub straps to the rear seat base. Google or search the forum for examples.

3) None of this is good for "street use only". You are actually safer using the stock restraints on the street. The purpose of the stock restraint system is to minimize injury in moderate (<60mph) speed accidents. It allows your body to decelerate over a distance while keeping it in a good position within the car frame.

The purpose of race restraints is above all else to keep you firmly confined and positioned in the race seat in a high speed accident.. It does not stretch. It is designed with the concept that I am much more willing to accept minor injuries like crack ribs, collarbone, sprained neck, mild trauma, etc, rather than be crushed to death.

Hope this helps,

-bill

Gene 09-11-08 10:34 AM

Stock belts also allow you to move around so you can look at traffic at a cross street and the like. I have harnesses in my T2 for when I go to the track but I use my stock belts on the street. Driver seat is a Corbeau something or other 1-piece bucket with a sub belt slot. Note that it is unsafe to use a sub belt wrapped around the front of a stock seat, it needs to go through a hole in the seat to work correctly. The purpose of the sub belt is not to retain you by your groin, it is to hold the lap belt low on your hips so the large bones in your upper leg take the force instead of your guts.

wvumtnbkr 09-12-08 12:41 PM

Thank you both very much.

The car is quickly turning into a track car only! I had a bit of a moment on track two weeks ago that got me thinking less about speed and more about safety. The car is only used occasionally on the street, but often for autocross, time trials, and track days.

I am looking for safety item suggestions that won't break the bank! I have no problem spending money on safety items, but don't want to put $3,000 of safety equipment in a stock TII either.

Any other suggestions regarding harnesses and seats? What seats do you run, with what harnesses?

THanks!

wrankin 09-12-08 01:41 PM

Thinking about safety first is A Really Good Idea. It doesn't actually have to break the bank, either. For an HPDE/TT/Auto-X car thats still used on the road, here is the short list:

Roll bar - good protection in case of roll-over and gives you a proper place to mount harnesses. $300-$350. SFI padding is a must for all bars above your shoulder level. A cage is not a great idea until make the car track-only.

Harnesses - go with 6-point ones, that way you can use them if you still have stock seats. $135/set for G-Force FIA rated. Keep your stock belts for use on the street.

At this point some folks would recommend a driving suit for fire protection. Not a bad idea. You can put this purchase off for a little while.

A true racing seat can now be considered. They are not that comfortable on the street. Here you may want to look at Ebay - search under "race sear" in Ebay Motors. Pay attention to the price though, sometimes you see bids that end up higher than list price. Pay attention to shipping costs, they can be quite high. I got my first seat (a basic Kirkey) on sale at Summit Racing (free shipping, woo hoo!!). I later upgraded to a Kirkey Roadracing seat that I found used on a local forum.

Figure $200-$500 per seat (and you can spend much more).

Also pay attention to seat mounting requirements. Aluminum seats really need a back brace. Others shells (anything FIA certified) do not. So you must figure in the mounting costs.

A small, properly mounted fire extinguisher (that is within reach of the driver when belted in) is not a bad thought either.

Remember, if you have an instructor (or a student) in the car with you, you must provide equivalent protection for them.

That would be my initial cut at the topic. Good luck

wvumtnbkr 09-15-08 09:36 AM

How would a 6 point allow the use of the stock seats? Could you please explain in more detail? Also, I do not have adjustable head-rests. Does this make a difference?

Thanks!

Rob

RacerJason 09-15-08 10:16 AM

Do NOT use 4/5/6 point harnesses with stock seats... you have to have extra rollover protection first, and a proper seat to accept the harness second. Read this thread of identical query for more information:

https://www.rx7club.com/showthread.p...hlight=harness

99% of "Stock" seats will not accomodate 4/5/6 point harnesses safely. Remember these harnesses virtually eliminate longitudinal and latitudinal travel in the event of an impact. Therefore in the event of a rollover and catastrophic damage to the roof your head will have a bullseye on it. A simple four-point cage with little change to the stock interior combined with a proper seat is the only true way to safey run a multi-point harness.

Gene 09-15-08 01:04 PM

The kirkey aluminum seats are nice, I have those in a spec E30 I'm building and by buddy has them in his PTE Integra. You have to fabricate your own mountings for them. If you get any FIA bucket it will have hardware mount points built in and you can get brackets and sliders for your car.

Black91n/a 09-15-08 09:21 PM

If you're using a non-FIA rated seat it'll be best to follow the rulebook and install some seat back braces, even if the rules don't apply directly to you.

Zerkster 09-15-08 10:13 PM

Well look who it is.. Mr. "Lets drift the autoX track"

2 things: :, I have 2; 5 point harnesses if interested, but you should usually have a rear cross bar to secure them to, also im not sure of exact specs but all harnesses need to be a certain hight/ distance as to not crush your spine in a frontal crash( if the shoulder bars are connected to low to the floor they will pull down instead of back in a crash)

Secondly, as for my car, Boost controller malfunction + Stock ECU without FCD but has no fuel cut + happy right foot =:bigeyes:

Replaced TPS, past issue resolved. I didnt blow the motor but my tires told me to go kill myself.( so did the honda next to me :lol:


(BTW 20PSI)


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