Rollbar Brace

[gbob]

I was competing at the weekend at a local hillclimb and was having a look at some of the seven based cars that were there.   Because they were in a road going class they didn't need a full cage but all had a rear roll-bar behind the drivers head.

There were a few interesting extras that people had added though and one in particular that I liked the idea of.

They had added a removable bracing bar that had a collar to fit round the rollbar and then bolted to the floor on the passenger side.

I was just wondering if anyone had done something similar on an exocet?

[gbob]

I think it was something similar to this:

[kiwicanfly]

If the bar was bolted just to the the standard floor I doubt it would add any extra strength to the roll bar, which I presume is what you were thinking of, as the aluminium floor held on by rivets would just rip out if loaded in that way. Note I only mean if loaded through the extra bar due to an incident.

You would need to attach the brace to something more substantial like a chassis member, preferably an intersection of two or more chassis members in which the bracing direction is correct for the load direction of the brace.

However what is it that makes you think you need this extra brace? The Exocet bar is diagonally braced at the rear already.

[gbob]

It was a chassis member I was thinking about connecting it to.

I'm not sure what makes me think I need it, but adding extra safety is never a bad thing while racing. I'm not sure what the"MSA Spec Rollbar" is and how it differs from the normal one? (thicker tubing maybe?)

[kiwicanfly]

Dont know what bar you have but the MSA spec, for a start, will have to be straight across the top tube, not M shaped.

I am not familiar with the full regs in the UK but there is a lot of crossover with NZ.

The tube material, diameter, thickness and method of manufacture will all be specified along with the method of attachment to the car and the number, and location, of braces.

The list goes on but is actually quite easy to achieve when starting from scratch.

Can be tricky, but not impossible, to retrofit without using welding.

My suggestion is to determine the level you wish to compete at and find the minimum regs for that level then see what else you wish to add for personal peace of mind.

Minimum on my Rocket was a MSA roll bar which I could have fitted instead of the M however I liked the M for road use.

In the end I created a bolt in cage that can be easily removed.

One big reason for going cage was the comment made to me about going through wire fences and losing my head - literally!

[gbob]

I’m just about to order my kit so haven’t made any decision as yet. I’m just waiting on hearing back from the local MSA and championship people regarding requirements around rollbar and safety constraints before I order. Depending on what class an Exocet falls into will depend on the requirements involved. If it's a road going class like I currently compete in with my MX5 then the requirements will be less.
I’ve been looking at some images online and like you I much prefer the M shaped bar to the straight bar. If only there was a half way house with a thicker, more supported M shaped bar.

[kiwicanfly]

The problem with the M is that it is not as strong along the top axis.