why does the headrest manipulate the spine?

Pauly

if i push my head back on the headrest kinda hard, the seat bulges around the mid-back area. what the heck is the purpose for that? has anyone noticed this? cloth seats by the way

__________________
Gun Metallic 2012 370 Z 7AT

Corona370z

I have noticed it but have no Idea why it is. Could be just how the seats are made. Would like to know why but could also live without knowing

__________________
Stillen Intake, ARK Exhaust. Hopefully in the near future: Tanabe GF210 Lowering Springs, Hotchkis Sway Bars, Motordyne M370 Intake Manifold.

snake1212

Active head restraints, used to reduce whiplash in case of an accident.

Zoren 370

Gauge

Neat, I've wondered this since the first day I got my car lol.

__________________
I am a demon bolt slayer.

kenchan

yah, when we push our head againt the headrest it feels wierd on our upper backs, but that's just the exast opposite of how it's designed to work. your upper back would push back first during a rear impact which pushes forward the headrest to keep your head from whiplashing.

Lug

You must have the standard options package. With the Executive package, not only do the headrests massage your back, they make sure you get a happy ending too!

__________________
keep Chubbs in your pocket - Chubbs

bigdog1250

Yep. When I first test-drove the car I was like is there something wrong with the seats? Then I figured out why it was doing that and thought

__________________
350z / 40th 370z / C6 Z06 / BMW M4 / V10 R8 / C7 Grand Spot / 997.1 GT3 / S2K / Camaro ZL1 / 718 GTS / 991.2 GT3

Pauly

i knew they forgot the mechanical arm that does the "old fashioned". im off to the dealer!

__________________
Gun Metallic 2012 370 Z 7AT

Pelican170

I dont buy that. Ive heard its a flaw in the manufacturing...

__________________
Fast Intentions CF Exhaust - Fast Intentions HFC's - HPS Tubes w/ AFE Dry Flow Filter's

Augustus

No, I think that's exactly what it is.

I've owned Saabs and Volvos that made a big deal about having active head restraints, and those did exactly what the OP is describing. If you pushed back on the headrest, you could move the mechanism inside the seatback and feel it on your upper back.

The idea is to minimize whiplash. Someone rear-ends you, your torso is pushed into the seat like you're accelerating, but obviously much more suddenly & aggressively. Active headrests use the inertia of your upper torso to pivot the headrest forward to help cradle your head in this type of accident.

If the Z has active headrests (anyone?) this is what the OP is feeling.

A couple of quick images illustrate how they work..

Volvo:


Saab:

FairladyZ

Z® Coupe 370Z® Active Head Restraints Photo | Nissan USA

BAM, no design flaw. Its on purpose.

Augustus

Pelican170

Interesting, but I hate it lol. Everytime I put my head back, i feel like a bar is digging into my back...

__________________
Fast Intentions CF Exhaust - Fast Intentions HFC's - HPS Tubes w/ AFE Dry Flow Filter's

Huck

Actually, all of you are wrong. It's made so that when a girl is on top of you in the car she can slam your head against the headrest while in the throes of passion, and you automatically pump her harder. You don't even have to do any work!!


On a side note, only midgets will fit on top of you in the seat, and it's really hard to find DTF midgets.


Sent from my iPhizzle using magic and new fangled science stuff

__________________