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      04-02-2014, 12:26 AM   #23
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If you have a full cage, fixed seat, and no airbags then I'd advise using your 6pt harness and a helmet with a Hans when driving on the street. I'd love to see the look on people's faces seeing you drive on the street with a helmet and Hans.
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      04-02-2014, 07:15 AM   #24
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Yeah, driving on the street with a HANS device... good luck when switching lanes...you're aware you can barely turn your head with such a device?

I've just purchased a full cage. My shop recommended me to install the rear part only (clubsport version) as long as the car is still occasionnally driven on the street, unless I want to wear a helmet all the time.
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      04-02-2014, 09:29 AM   #25
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Quote:
Originally Posted by Autobahn335i View Post
Yeah, driving on the street with a HANS device... good luck when switching lanes...you're aware you can barely turn your head with such a device?

I've just purchased a full cage. My shop recommended me to install the rear part only (clubsport version) as long as the car is still occasionnally driven on the street, unless I want to wear a helmet all the time.
ya i think its pretty obvious doing a rear 4pt is the best option....
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      04-02-2014, 09:33 AM   #26
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i appreciate most of the responses i got and i think my orig question was pretty much self explanatory but needed to hear it from other members.....

some other responses not sure if serious but thank you anyhow....

im going to stick with the orig idea and go with a 4pt...
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      04-02-2014, 09:38 AM   #27
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I think what you also forgetting is how far your head can travel without hitting anything.
The cage takes up the space inside the car, making your overall "free area" smaller. That will make you more likely to hit the head against the cage during small impact than hitting car pillar if you did not have the cage.

I always heard, and personally believe that if you get a cage, you should wear a helmet.
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      04-02-2014, 09:39 AM   #28
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Quote:
Originally Posted by jbraslins View Post
I think what you also forgetting is how far your head can travel without hitting anything.
The cage takes up the space inside the car, making your overall "free area" smaller. That will make you more likely to hit the head against the cage during small impact than hitting car pillar if you did not have the cage.

I always heard, and personally believe that if you get a cage, you should wear a helmet.
ill say it again...



i appreciate most of the responses i got and i think my orig question was pretty much self explanatory but needed to hear it from other members.....

some other responses not sure if serious but thank you anyhow....

im going to stick with the orig idea and go with a 4pt...
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      04-02-2014, 04:59 PM   #29
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Quote:
Originally Posted by Sebringjetta View Post
ill say it again...



i appreciate most of the responses i got and i think my orig question was pretty much self explanatory but needed to hear it from other members.....

some other responses not sure if serious but thank you anyhow....

im going to stick with the orig idea and go with a 4pt...
Why a 4pt harness and not a 6pt harness?
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      04-02-2014, 07:02 PM   #30
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One main thing nobody has mentioned is the contact area of a bar versus standard inside car surfaces. If you head hits lets say the b-pillar, it is hitting a rather flat surface which allows the load of the impact to be spread over a rather large area of the head/face (also the surface deforms along with the head sliding on the surface, etc).

For a roll bar/cage bar, let's look at it unpadded for a moment. Think of the skull impacting the bar. The actual contact area is *very* small, a small piece of the outside radius of the bar times some small length of skull. The local stresses on the skull with be very high as little of the skull can "wrap" around the cylindrical surface to spread out the load area without significant damage. Hence one of the main concerns is that locally very high potential stress and the corresponding damage it causes.

Add the padding, and of course you increase the radius of the bar to some extent (slightly increasing contact area), but that might be negated by local compression of the padding upon impact. The basic nature of the problem that doesn't exist in normal car interiors still exists (very hard surface with very small contact area).
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      04-02-2014, 07:43 PM   #31
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You can clearly see the seat move. Not sure how fast this was but it also doesn't flop around.

As I've said...as long as the cage is designed with these things in mind then you MINIMIZE the chances...not eliminate...of smokin' your head off of a steel bar.

Also keep in mind that composite seats do flex.

At the track, a GT3 hit a wall rear end first. Both OEM seats broke which resulted in the driver's helmet shattering the window. Yes, the seats were fully reclined because the motor mechanism broke.
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      04-02-2014, 07:52 PM   #32
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How fast can you get out of your car in case of fire ? U do know that in race cars some racing organization time you and that dictates the size of you fire system
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      04-02-2014, 10:49 PM   #33
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Quote:
Originally Posted by USCTrojanMan29 View Post
Why a 4pt harness and not a 6pt harness?
4 pt cage....6pt harnesss
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      04-02-2014, 10:52 PM   #34
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Quote:
Originally Posted by bigjae1976 View Post


You can clearly see the seat move. Not sure how fast this was but it also doesn't flop around.

As I've said...as long as the cage is designed with these things in mind then you MINIMIZE the chances...not eliminate...of smokin' your head off of a steel bar.

Also keep in mind that composite seats do flex.

At the track, a GT3 hit a wall rear end first. Both OEM seats broke which resulted in the driver's helmet shattering the window. Yes, the seats were fully reclined because the motor mechanism broke.
I use recaro pp..not sure exactly how they hold up in that situation
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      04-02-2014, 10:54 PM   #35
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Quote:
Originally Posted by jrse92m3 View Post
How fast can you get out of your car in case of fire ? U do know that in race cars some racing organization time you and that dictates the size of you fire system
Yes depending on our run group we have to pass that test... except the door is closed and we have to go out the window...so not sure what you mean as far as having to do with the cage
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      04-03-2014, 02:20 AM   #36
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Quote:
Originally Posted by bigjae1976 View Post


You can clearly see the seat move. Not sure how fast this was but it also doesn't flop around.

As I've said...as long as the cage is designed with these things in mind then you MINIMIZE the chances...not eliminate...of smokin' your head off of a steel bar.

Also keep in mind that composite seats do flex.

At the track, a GT3 hit a wall rear end first. Both OEM seats broke which resulted in the driver's helmet shattering the window. Yes, the seats were fully reclined because the motor mechanism broke.
Which seats did it has? The comfy heavy ones or the lighter CF bucket seats?
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      04-03-2014, 09:11 AM   #37
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I thought you only had a back half cage? If you have a 4pt cage don't need to pad the bars unless its built wrong. My head would have to come off for it to hit my cage. Then I don't care.
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      04-03-2014, 09:30 AM   #38
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Quote:
Originally Posted by 1MOREMOD View Post
I thought you only had a back half cage? If you have a 4pt cage don't need to pad the bars unless its built wrong. My head would have to come off for it to hit my cage. Then I don't care.
we had thoughts of doing a clubsport style full cage... like what goes in the 997 gt3....
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      04-03-2014, 11:48 AM   #39
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Quote:
Originally Posted by Sebringjetta
Quote:
Originally Posted by bigjae1976 View Post


You can clearly see the seat move. Not sure how fast this was but it also doesn't flop around.

As I've said...as long as the cage is designed with these things in mind then you MINIMIZE the chances...not eliminate...of smokin' your head off of a steel bar.

Also keep in mind that composite seats do flex.

At the track, a GT3 hit a wall rear end first. Both OEM seats broke which resulted in the driver's helmet shattering the window. Yes, the seats were fully reclined because the motor mechanism broke.
I use recaro pp..not sure exactly how they hold up in that situation
So why are you worried about a cage for a street driven cars? No one really has any facts so far just like you don't know what exactly a recaro PP seat will do.
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