5 replies to this topic

[Tahiti Joe]

Hello all! Right then, so the time has finally come where i am able too start preparing a Mini for stage rallying. I have a very good donor vehicle, and its one that i know very well, being my old daily drive! The car is a 1993 Tahiti 1275, the shell is in very good condition, and as far as i know pretty rust free as i have looked after it meticulously for the last 2 years!

Anyway, the shell is almost completely stripped interior wise so im getting to the point where i'll soon be able too start preparing the shell. Obviously the shell will need the support plates for the roll cage and the like (Safety Devices 6 point bolt-in), but are there any places that the Mini shell is particularly weak and needs reinforcement? I've worked on several Escort shells before and these need practically everywhere seam welding and tacking! Wondering if the Mini shell requires the same?

Cheers in advance!
Joe.

[Sputnik]

With a decent roll cage, I think the shell is ok?

It is the subframes, especially the front one, that needs some work. Also look at the mounting points on the floor area.

Edited by Sputnik, 19 May 2012 - 01:38 AM.

[Cooperman]

The main places to re-inforce the shell on the later cars - the ones which originally had rubber-mounted front sub-frame - are as follows:

The floor area where the front sub-frame is fixed.
The transverse box-section cross member which should be double-skinned right across.
The rear sub-frame front mounts inside the sill/heel-board interface. Just plate the inside of the inner sill locally.
The front damper mountings onto the inner wing.
The tops of the rear damper mountings by adding webs down the inside faces and extra metal at the tops.
Inside the boot on the floor where the rear sub-frame rear mountings are bolted through.

The front sub-frame needs extra strength especially at the 'ears' where the front tie-bars are attached. Add triangular 4 mm steel plates as extra support.
The front sub-frame can be seam-welded around the cross structure to the towers and extra metal sheeting, say 2 mm thick, under the flat portion below where the lower arm is attached.

Weld the cage to the shell with plates at the top of the A-posts and with a large triangular plate betwen the B-post 'hoop' to the B post. In fact this plate can be bolted to the seat belt mountings on the B-post.

[bmcecosse]

Cross member under the seats kinks in the middle. Reinforced seat mount points. Rear damper mounting points need some attention - and pads on the boot floor where the Aeon bump stops will sit..... And of course you need to 'flameproof' the front and rear bulkheads. Skid plates under the front floors (rear of wheel arch) - and at the rear just in front of the rear subby. And likely you will want to raise the battery box - and protect it's leading edge...... And the rear arches should be raised to stop the tyres locking up inside the arches......

[icklemini]

Can you fit anything 'better' than a 6 point cage?

Although the 6 point bolt in cages work in protecting the driver... they dont really add a great deal of strength to the car - a lot of damage can be done to the car even with a 6 pointer fitted...

Carefull with what you reinforce... if you have a uber strong subframe, when you have an 'off' the energy will go into the shell... and a 6 point cage doesnt have any reinforcement 'up front'... Its easier ( and cheaper) to change a bent front sub frame than it is to straighten out the front bulkhead for example

[Cooperman]

Some people run standard front tie bars as they will bend, but can be replaced in about 5 minutes per side.
The basic Mini shell has proved itself to be very strong over years of rallying. it is best to weld the cage in if you can, but mine is bolted it in and when I rolled the car it held up very well and all I needed was a new roof panel. Mine is 6-point.