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View Full Version : Roll-over hoop, braced or unbraced?


aerosam
7th August 2009, 08:01 PM
Hi guys,

I recently installed the roll-over hoop onto my chassis (welded rather than bolted on) and I'm wondering if there is much benefit from bracing it to the rear. Just having a quick flick throught the classifieds it struck me that most of the major manufacturers don't use any. Dax, pilgrim, wesfield, tiger, sylva, vidicator, mk, none i saw had braced hoops.

It looks good without them and unless it would seriously compromise the strength of the chassis I'd like to leave them out.

Chris Gibbs
7th August 2009, 08:17 PM
It's personal choice really. If you were to have a roll over accident the back stays would help to prevent the roll bar folding but in the end it's your car.

Cheers

Chris :)

HandyAndy
7th August 2009, 08:29 PM
apart from as Chris has said, when i,ve been building my car, i have the back stays going all the way down to the bottom corners of the chassis which in my opinion looks like it would also give a bracing support to the tank area in the event of a rear end shunt,
tho that is my thoughts only but seems logical.

cheers
andy:)

aerosam
8th August 2009, 08:22 PM
Chris, sorry, I didn't mean to question your design, I'm sure the backstays make the car safer in an accident.

Andy, bracing all the way to the floor is also a great idea, but TBH the fuel tank area in mine is already very strong by vitue of the fact that it contains a honking great big chunk of BMW rear axle carrier in it.

As long as omitting the backstays does not make a hige difference to the overall strength of the chassis I think I'll go without.

davidimurray
8th August 2009, 08:44 PM
Personally, I wouldn't remove them. Think when your car is upside down sliding down the tarmac (or even worse a field) on the hoop. There will be a huge bending moment applied at the base of the hoop. There are 3 likely scenarios that could lead to failure, 1) the bolts shear - unlikely, 2) your weld to the plate fails - unlikely, 3) the suspension mount plate deforms - possible.

The brace basically allow the load into the hoop to be better distributed t other parts of the car - and that includes slidin forward and backwards as well as the triangulation providing stiffness.

raceral
13th August 2009, 03:01 AM
I took mine down to the outer lower corners for the same reason Andy mentioned, extra roll over support and fuel tank protection in case of a rear ender, or if I was foolish and spun the car around in a 360 and banged something.
Al

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