Roll Cage tied to Front Subframe Mounts
Turbo Mini Forums

Hi all, I have welded in a full cage, and as I'll be rallying this mini I'd quite like to tie the cage into the front subby mounts to stiffen it up a bit. Only real question is where exactly do people generally weld the front of the tubes to? The bulkhead has a gap between it and the tower bolts where they are boxed in through the front cross member, or with a spreader plate is that good enough?

If that makes sense?

Thanks,
TC

www.topcatcustom.co.uk

Nobody know anything about this?

www.topcatcustom.co.uk

I'd just tag it to the cross member where the subframe tower bolts go to.

Also run a bar along the bottom of the bulkhead/floor to pick up the loads tranferred to there too.

Only my opinion though.

Just look through photos of how others have done it. Jimsters cage looks just the ticket.

Cheers, I guess with a spreader plate against the cross member it will be pretty good. I've wondered if those small tubes that run horizontally to pick up the lower mounts actually do anything at all, its about an inch tube over a metre long with pick ups on it's side, which doesn't seem to me like there would be any strength in it..?

www.topcatcustom.co.uk

Mine goes through what was the air vent hole and next to the tower bolt

Rich

Avon 2010 class c 3rd
Avon 2011 class c 2nd 13.8 @ 98mph

I've been lurking here long enough so I thought I'd finally join and answer this question. I asked the gentleman who installed my rollcage to do the same thing and here is what he came up with:






Notice in this photo the small plate of steel welded in as additional support for the coilover mounting brackets.





I don't know that that is the absolute best way but it might give you some ideas. Also, if you take a look at the book 'The Last Works Minis' you'll see they did something similar.

Thought I'd just update this, I actually cut through the cross member right beside the tower bolts, passed the tubes right through and made them act as my front subframe tie bars too, should all be very stiff when finished, I will also tie in front shock mounts for if I use coilovers. Got to weld them all up yet but here's the basic idea.







p.s. it's easier now I forked out for a roll cage tubing bender!!

www.topcatcustom.co.uk

Nice but where is your rear seat/bulkhead?
A lot of rigidity in that panel!

On 5th Sep, 2011 Vegard said:
I stand corrected. You should know

All been chopped out and cage is tied fully into rear turrets, shell etc, I think I'm going to replace it with ally bonded all the way round, it's so easy to work in the shell with no rear bulkhead!!

www.topcatcustom.co.uk

Looks like a nice tidy job.

It'll be interesting to see how much it weighs in at.

https://www.facebook.com/pages/Fusion-Fabri..._homepage_panel

www.fusionfabs.co.uk



1/4mile in 13.2sec @ 111 terminal on 15psi

Why not? SO long as the fuel tank is located out of the driver/passenger compartment (MSA words), it is fine, was originally going to fabricate a flat tank to sit inside/above the rear subframe and have the boot floor tubbed upwards to house it, keep the weight right down low and still legal, however I know it's not the original design, but I'm not intending on doing historic rallying with it.

www.topcatcustom.co.uk

Need to read the blue book and section on taking out structural panels! Definitely in eligible for any sprinting - not sure about rallying. Certainly no go for racing.

On 5th Sep, 2011 Vegard said:
I stand corrected. You should know

Is it classed as structural? I know it does provide a lot of stiffness but I have put in a hell of a lot more strength than I have taken out, and most other cars I see that come through the workshop have got aluminium rear bulkheads riveted and bonded in. It's not a big issue as can put it back in if need be, but would rather do it in ally or carbon.

www.topcatcustom.co.uk

As soon as you start replacing structural parts with rollcage as opposed to simply uprating the shell you are into spaceframe territory and thus into sports libre. Fast Carl's best buddies the Deppers even have a shorter fibreglass front and part of the original wings. Some say this is so they can protest people with conventional removable front ends. But yes you need the original rear seat/bulkhead back in. I should add I sprinted Scruffy from 1989 to 2008 before I left the UK so have seen most things people have tried and failed at MSA wise.

Edited by Scruffy on 1st Apr, 2012.

On 5th Sep, 2011 Vegard said:
I stand corrected. You should know

Thanks for the reply, most of the cars I looked in at the last rally I went to had carbon or ally main rear bulkhead panels, so can I assume this is ok so long as it is still sealed all the way round? I'd ideally like to put a steel edge in and rivet/bond carbon to it as a main panel.

www.topcatcustom.co.uk

Best thing to do is phone a scrutineer who does MSA log booking - you'll need one of these anyway and that way you'll know either way.

On 5th Sep, 2011 Vegard said:
I stand corrected. You should know