Rear subframe strengthening

[Mini-geek]

Any advice on strengthening a new genuine rear subframe?

I was thinking of just seam welding it, but I wonder if it's worth adding some gussets and maybe make the inner section thicker where the arm pin bolts through


It's on a track focused car I've currently got a non genuine one on and I want to replace it with a better one..

[Polarsilver]

assuming it is a dry car rear subframe with a "side exit" exhaust .. i first put in captive nuts to take the Exhaust cotton reel rubber mounts .. then box in the rearmost cross member on the rear subframe so it is no longer an open channel .. ..add only small gussets each end as clearance for Battery Box & Silencer are needed .. with this area strengthened with the Tolley Jack placed in the middle of the rear subframe crossmember its so easy to lift the entire rear of the car as it is a balanced lift.
helps to also add a Trolley Jack contact pad in the centre underside of that boxed in area
Drill through the new box section on the off side to add a rear Tow Eye

[Peter Laidler]

On the other hand, if it's predominantly a track racer and lightness is the name of the game, does the rear sub frame need beefing up?

[Mini-geek]

I've always been told that the front subframe is way over engineered so needs lightening (and some amount of strength adding) but the rear should not be lightened. Just strengthening

[Spider]

The stock rear subframe really quite strong, much stronger than they look and keep in mind where and how it's bolted up to the body, further enhancing it's strength. When we go on Safari in our Mokes, we have just about the weigh of the empty car in the back and for the most part, we just run stock Moke rear subframes. These do have a small additional plate added to each side, but otherwise are the same as Mini items. Added to our subframes 'woes' is the longer trailing arms and a 40 litre aux fuel tank bolted in to them yet they stand up to all we dish out very very well.

For a track car, about all I'd be doing of it was mine is remove the rubber mounts and go to solids and possibly box in or add an angle to the rear rail ONLY so it can be used as a jacking point.

[Catmint]

Vizzards "how to modify your mini" has a page on this for rallying, basically seam weld and gusset the corners