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five point harness

Discussion in 'Gen 2 Prius Accessories & Modifications' started by theorist, Jun 30, 2006.

  1. theorist

    theorist Member

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    Has anyone installed a racing style drivers seat with a 5 point harness, especially in a 2004-2006 Prius?

    I'd love to hear about your experiences doing so. If you want to share your experiences with this modification to other cars or the fruits of your research into doing this with a Prius, I'd welcome these as well.
     
  2. GasGuzzler87

    GasGuzzler87 New Member

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    I bet it's been done. I don't know why, but I'm sure it's been done.
     
  3. jamesfchumbley

    jamesfchumbley New Member

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    <div class='quotetop'>QUOTE(theorist @ Jun 30 2006, 10:54 PM) [snapback]279509[/snapback]</div>
    The advantage, and it is a HUGE one, is that during a collision you are not twisted around the shoulder belt; your body is restrained in its normal orientation.

    I would pay $1,000 to have one installed in just my driver's seat.

    I have been disabled for 11 years because of being struck by a deputy sheriff, who ran a red light, hit my car on the left front quarter, and twisted me around my shoulder belt. It broke a lumbar vertebra and really hurt me.
     
  4. tnthub

    tnthub Member

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    The first problem is that the vast majority of 5-points are not street legal due to the lack of DOT approval. Although legal for the race track, the lack of a DOT approval means they are illegal for street use which could create a liability problem in the event of a catastophic accident.

    That said, they are certainly safer than the typical 3 point harness issued with a stock vehicle. Disadvantages are you cannot reach forward to pick something up off the floor if you drop your change going through a toll booth. The installation needs to be done by a professional who understands how to secure the harness appropriately to the frame/floor.

    Racing seats may be installed in any vehicle. They also need to be securely attached. Since racing certifications are not required for seat use is is likely that someone could attach new seats to the existing floor mounts and retain any power seat options. That is what I did in my Camaro.

    A major disadvantage to a racing seat are the high sides in the bucket area which require someone to lift themselves over the seat to get into it. Beyond that comfort is also an issue as racing seats are not comfortable for most people, although a good stitcher could create excellent covers that would take care of that problem.

    My Camaro utilizes Kirky brand aluminum lay back buckets and Kirky seat covers. I have absolutley no problem with comfort and have driven from maine to Ohio several times without incident or any stiffness. however my wife finds them extremely uncomfortable for even short trips. I do use a 5-point harness on the street as well since 99 times out of a hundred I am the only person in the car.
     
  5. Presto

    Presto Has his homepage set to PC

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    One of the other disadvantages which law enforcement keeps pointing out in rice capital of Western Hemisphere, Vancouver is the hinderance of other people's ability to pull you out in the event of an accident. There is a lack of knowledge by the general public to deal with 5-point harnesses.

    The Prius in it's stock form has a lot of body roll due to it's squishy tires/suspension, and chassis flex. Suspension upgrades will keep you more firmly planted in your seat and give you a better driving experience vs a 5-point harness.
     
  6. tnthub

    tnthub Member

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    A camlock is pretty self explanatory in the event of release... I can't imagine someone not knowing how to open it...
     
  7. naterprius

    naterprius Senior Member

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    Please consider when installing five-points: The uppers need to go on the ceiling, otherwise the belt will crush you down as you go forward. The celing may not be strong enough, and you may need a roll bar to attach to.

    Also, you will lose the side bolster airbag when you replace the seat. (Unless you bring it with you to the new seat).

    Nate
     
  8. derangedazn

    derangedazn New Member

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    As stated before, not many 5-Point are DOT approve. Also the shoulder straps needs to be no less than 70 degrees from the floor, or else it will induce a crushing effect which mean it can increase load to spinal/vertebral column....resulting in severe injury. Next is that most 5-point harnesses are attached to a roll cage. I doubt you will rip apart the interior just to get it installed.
     
  9. theorist

    theorist Member

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    Thank you for all of your very well informed and helpful replies. I truly didn't know what all was involved in properly installing a 5 point harness. It looks like I'll be staying with the OEM 3 point seatbelts.
     
  10. tnthub

    tnthub Member

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    Yea, I have a six point welded roll bar in my ride. No bars beside the head (dangerous on the street), and plenty of clearance between the seatback and the hoop bar (NHRA spec). The bar stiffens the car significantly but the welding needed to be done just right. Interior had to completely be removed. The bar then had to be painted and padding needed to be installed. Interior then had to be replaced. It was a lot of work.
     
  11. GasGuzzler87

    GasGuzzler87 New Member

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    <div class='quotetop'>QUOTE(James F. Chumbley @ Jul 1 2006, 08:07 AM) [snapback]279638[/snapback]</div>
    That's an oxymoron because bolting to the frame or floor is improper in itself unless you enjoy spinal collapsation.

    Rules for installation.

    The harness must be bolted to a roll cage, belt bar, or other locartion DIRECTLY BEHIND the seat so that angle of belts leaving the seatback must be no more than 95 degrees and no less than 70 degrees (floor/ frame is about 10 degrees or less and will compress your spine in a collision). Belts must be able to rest on a flat surface parralell to the floor, such as an area inbetween headrest and seatback or in speacial belt, cut-out holes but NEVER wrap around the sides of the seat (doing so may result in dislocated shoulders). Brackets must be bolted in a way that the bolts goin ginto the bar, or mounting place, are parallel to the direction that the belt exits the bracket location and NEVER at 90 degrees of the belt exit location. Angles within in 8 degrees of either direction are acceptable. Belts should be replaced once a year and brackets once every 3 years.

    With aproper 4 or 5 point harness, you cannot move at all from the seatback and it is highly improbably for street use. Things like agjusting the radio become a chore and are more distracting. If you plan on driving daily with the harness it is not reccomended. DOT approvals may also be an issue and in a vehicle with a full SRS system installed with air bag and all, the harness may change effects of the system and collision could prove to be more harmful (example is your back held in place with a curtain air bag knocking your head to the side and breaking your neck or causing whiplash). You SRS is designed to take appropriate measures depending on the accident. Air bags will not always deploy if the system feels the situation doesn't need it. Often people say they "wrap around" the shoulder belt and hurt their back or shoulder. This, in most cases, is result of having the seat too far reclined or slid back on it's rails. Or improper use of the belt. Other cases are if the driver is too small or too large to fit the specifications of the SRS system (160 pound male is what it is designed for but works for most people). I have a freidn who works on installing and engineering the SRS system in th eMazda6 and this topic has already been brought up on th eMazdaforum. I reccomend you use the stock belt.
     
  12. tnthub

    tnthub Member

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    To clarify... My seat has slots for the harness to come through on each side, and for both shoulder harness'. The bar came from Wolfe Racecraft and the top belts are secured to the horizontal. The two bottom side belts utilize the stock belt locations. The front belt had a Wolfe provided attachment bar.

    The actual roll bar needed to be installed to NHRA specifications and additionally required plates for insuring the bar was rigidly mounted to the frame (can't have the unibody floor ripping out).

    It is correct that a person is securely in the seat when the belts are latched. To have movement would be dangerous. I cannot reach the ashtray but there is no ashtray to reach, nor does the radio still inhabit the dashboard, and the shifter (manual valve body) is mounted specifically for my seating position. The pushbutton start is within reach as are the basics such as lights, turn signals, defroster, and wipers.

    I can reach stuff in the passenger seat (also a 5-point), so that is where I keep stuff I need to access while on the road. There is no more center console or back seat. There is no sound deadener under the carpet and there is no underbody coating any more. It is a loud, obnoxious, and rough ride with 28" x 7 1/2" x 15" front tires and 28" x 12 1/2" x 15" rears with 90/10 shocks up front and no sway bar. But the ABS works flawlessly and I drive slow so it is fine for what it is. Plus, 28mpg from a 383 stroker engine coupled to a TCI 700R4 manual valve body with manual lockup, and 3.73 gears in the Moser 12 bolt isn't too bad all things considered.
     
  13. GasGuzzler87

    GasGuzzler87 New Member

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    <div class='quotetop'>QUOTE(tnthub @ Jul 8 2006, 06:23 PM) [snapback]283112[/snapback]</div>
    Yep, that sounds about right. Must be a fun car. What kind of car is it. (threadjacking but the owner came to a conclusion)
     
  14. tnthub

    tnthub Member

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    Shhhhhhhh. It's a 1994 Camaro.........