289 fia rollbar height with hardtop

[peterpjb]

as far i can recognize every car has a different rollbar height,

it differs approximately between 28 cm (11") and 38 cm (15") on my car, (body to top in the middle)
to fit the rollbar under a lemans hardtop the maximum is around 30 cm 11"-12",

some lemans hardtop are equipped with a bubble to give space for the higher rollbar,

so i have two possibilitys:

- shorten the rollbar (easier, looking better)

- add a bubble to the hardtop (not so easy, safer(?), looking(?))

what do you think are pros and cons ?

[Blas]

If the roll bar (hoop) is to be functional it must project above the drivers head or helmet. (Something like 2" I believe) if it is too short, your head becomes the safety hoop. Modifying the bar height also requires modifying the forward brace length and angle. I believe the "Gurney Bubble" in your photo is more related to the helmet of the driver not limited by the roof height. There is another design for the rollbar. If I can find my photo I'll send it to you if you email me. I think there is a hardtop in in design for your car.
Blas

[peterpjb]

Originally Posted by Blas

If the roll bar (hoop) is to be functional it must project above the drivers head or helmet. (Something like 2" I believe) if it is too short, your head becomes the safety hoop. Modifying the bar height also requires modifying the forward brace length and angle. I believe the "Gurney Bubble" in your photo is more related to the helmet of the driver not limited by the roof height. There is another design for the rollbar. If I can find my photo I'll send it to you if you email me. I think there is a hardtop in in design for your car.
Blas

the hardtop has its highest point above the driver,
depends also if riding on normal street seats or racing seats, the racing seats maybe 3 or 4 " lower...

[G-Pete]

3 inches more or less make NO significant difference in case of a roll.

[G-Pete]

You hit the head - so or so - without a full cage.

The funny part is, that the guys with these high (ugly) roll bar hoops do NOT strap them in the car.
What I mean strap down, not just have the harness lay on you. As long you can move forward, the same movement will be vertical in a roll accident.

BTW, this is how it looks like when you roll and land upside down off-road. Yep, the 3 inches made a big difference.>>>>

[Blas]

"...Do you want to live forever?" - Conan The Barbarian

[peterpjb]

for sure not!

another question: rollbar chrome or black?

[CompClassics]

That would depend on what you are trying to do with the Cobra, 1964 1965 FIA team cars are black, depending on which USRRC Cobra it could have been chrome or black.

[DanEC]

Originally Posted by G-Pete

You hit the head - so or so - without a full cage.

The funny part is, that the guys with these high (ugly) roll bar hoops do NOT strap them in the car.
What I mean strap down, not just have the harness lay on you. As long you can move forward, the same movement will be vertical in a roll accident.

BTW, this is how it looks like when you roll and land upside down off-road. Yep, the 3 inches made a big difference.>>>>

What's the story on this? Looks to be a CSX car or Kirkham from what I see.

[G-Pete]

Back in 2010, a rally over 5 days from Brooklands UK to Monte Carlo FR. It was an 2008 Kirkham.

[G-Pete]

Here is a good example (actually BAD) for too lose harness and roll bar mount attachment points.

In the slowmo you clearly see how far the pilot get 'ejected'. Thank god he got only his ego bruised.


[ame="https://www.youtube.com/watch?v=CQkqkOwuqac"]https://www.youtube.com/watch?v=CQkqkOwuqac[/ame]

[db replicas]

Originally Posted by G-Pete

Back in 2010, a rally over 5 days from Brooklands UK to Monte Carlo FR. It was an 2008 Kirkham.

I heard it was an AC Mk4.
Tie down hoops under the rear end and the front outrigger is not as Mk3.