8 replies to this topic

[Ianm11]

Hi just wondering if both rear arches have to be cut aswell as the fronts when fitting 12x6 mambas. Or is it just the fronts. Also do reinforcements need to be used? I presume if i use the minispares cutout diagram ill be ok? Ill be using group 5 race arches.
Thanks again

[nicklouse]

It all depends on the set up of your car. Generally the rears are left alone as they don’t need cutting but Tubbing.

 

if your car is standard ride height there may be no cutting needed. But when lowered cutting is often needed with any wheel size at the front.

[Ianm11]

It will probably be lowered just wondering if i follow the minispares template from there website? Thanks again

[mab01uk]

The Minispares Templates in link below are for Sportpack Arches and 13" wheels:-

http://www.minispare...itting-template

 

6 x 10" and 6 x 12" wheels usually need much less of the front arch cut away (when compared to 13" wheels) depending on the alloy wheels offset and even then only towards the front edge to clear the tyre on full steering lock.

The best way is to fit your wheels and then see what the clearances look like on full lock and with your planned ride height, then mark the front wings with a cut line to suit, while allowing some extra metal to bend up and reform the small arch flange to avoid having a sharp metal edge facing the tyre and to add back strength to the wing and front panel. Towards the end of the front bumper is the maximum area that can be cut away and there must be the space to fit and attach your chosen wheel arch extension plus you need to keep checking where the arch extension will fit and attach, perhaps with a little flex to the arch extensions profile in some cases.

Remember it is always best to measure twice and cut once as it is very hard to put metal back!

 

The rear arches do not need modifying on a road going Mini unless you intend to lower the car to an extreme or intend to build a race spec Mini which won't need to get over speed humps or avoid all the potholes in our roads!

'Tubbing' the rear wheel arches as mentioned above is also much more involved than just cutting back a single skin front wing panel and involves welding in new metal to the bodyshell and is not easily reversible....even the Sportpack MPi Minis with 6 x 13" alloy wheels and 175/50 x 13" tyres had standard rear arches with no bodyshell mods at the rear.

Edited by mab01uk, 17 November 2024 - 09:43 AM.

[Ianm11]

Thanks for that info. I dont have wheels at the moment. Car is going to the bodyshop this week so wanted to give him an idea of what i need cut

[coopertaz]

you only need to cut the front of the front arch, unless going really low. if you cut just inside the mounting holes for the original arches at the front edge then reform the lip that will give you clearance and enough left to attach the gp5 arches

[Midas Mk1]

I'll be honest, wait till you have arches and wheels -  ill fitting arches on a Mini can look bad.

Edited by Midas Mk1, 19 November 2024 - 12:27 PM.

[nicklouse]

Thanks for that info. I dont have wheels at the moment. Car is going to the bodyshop this week so wanted to give him an idea of what i need cut

Untill the car is fully assembled and suspension set and metal cut I would not send to paint.

 

or be prepared to cut the painted metal where needed.

[Cooperman]

When the arches are cut, the flange is removed and the wing loses some rigidity.

I have just replaced original flanges back onto a 1992 car which had had the arches removed and was surprised at how weak the un-flanged arches were after removal of the fibreglass extensions.

The rebuilding was done by getting some old wings, which had been removed due to rust in the usual places, cutting the flanges off with around 75 mm of wing and welding the flanged pieces back in place, using one of my other cars to establish the correct flange position. The wings now feel solid again.