Niva Resource: Wheel-arch trim

Trimming the Wheel Arches (for greater tyre clearance).

trimmed wheel arches trimmed guards

Fitting tyres much larger than about 28" to a Niva may necessitate some wheel-arch (mud-guard/fender) alterations (or a lift). Basically there's 3 types of trims: a basic beating of the lower guard, a whole arch tim, and extreme trims.

Click on images for a larger view.

1 Lower guard beating/cut

The problem areas are usually the bottom rear of the rear wheel-arch, and the bottom front of the front wheel-arch (or sometimes the bottom rear of the front arch if you run a lot of castor). These can be addressed by a bit of panel beating and re-working these areas back a few cm. It can be done without even needing to cut anything. This is what I have done. It's easy, and should happily accommodate 28" tyres. If you do decide to cut, fold the edges back or use some edging to stop it cutting your tyres if they do ever make contact.

Lower guard beaten

See more examples below.

2 Cutting around the arch

If you need more clearance you'll have to start cutting. You can follow the factory line around the arches, and fold a new lip in, which will give you around an extra inch.

Before

After

See more examples below.

Note the rear arches of the Niva is double skinned so will require some welding because this will separate the 2 skins.

Inside rear guard (untrimmed)

Rear skins separated

Welding the skins together after rear trim

Some people have done versions of this trim without separating the rear skins (ie no welding needed), as in the below image, but as the body is monocoque I'm imagine this risks weakening the structure.

Here's a guideline, in Russian sorry, but it's obvious enough (top is the front, bottom is the rear):

Here is a DIY arch-trim guide; it's for a Range Rover but same theory applies to the Niva (just be aware of the problem above if you separate the rear skins).

Alternately the guards can be skillfully rolled up under the guard with a hammer instead of being cut:

Here's how

Big arch trims
You can trim past the arch line on the front to get a big arch trim, but there is a limit before you need to start cutting into the inner arches, sill, and floor. Typically these cut around the front valence under the headlight.

3 Extreme

Simply cut as much as you need out (ideally avoiding things you don't want cut) and weld in plates to fill the gaps, reinforcing any structures you weaken by cutting. Clearly you'll need decent welding/fabricating skills.

See more examples below.

WARNING If your Niva is ever to be used on the road, don't forget to check local legislation before cutting into parts of your car's body, especially anything that's more than a simple trim.

And remember to paint any bent or cut steel (both inside and outside the arch) asap to stop it rusting.