240 - REAR FENDER TIRE CLEARANCE
This article describes modifing the 'rear fender outer edge' to create wide wheel clearance. Click all pics to enlarge.
Most 140 & 240 owners have experienced tire / tyre rubbing on the inside of the rear fender when going up a driveway at an angle. The panhard rod doesn't help as it moves in an arc moving the chassis closer to the wheels at times. Combined with wider tires / tyres; wider rims (7, 7.5, 8" with different offsets) and shorter springs, the wheel will be very close to the outside fender. Low offset rims eg 0-20 mm can be correctly positioned with wheel spacers that attach to the brake hub / wheel mount face. When combining wide rims and motorsport you need all the clearance you can get. There's nothing you can do to the inside of the fender, but mods can be made to the outer lip.
240 rear wheel arch
at the photo, you'll probably notice the wheel is not
centred in the arch. There all like that. The wheel should
be further forward (or the arch further back), not the best
The fender folded edge is tough, with two layers of panel, each 1 mm thick, spot welded together at intervals.
The Pinch Point
The rear fender is good and wide at the top, and then it arcs down, closer and closer to the tire. This results in a pinch point and covers about 100 mm or 4". The Pinch Point area is what is being worked on in this article.
MODIFICATIONS - Aiming for a rear guard clearance of 315 mm
Click to enlarge. This photo was taken after the lip had been re-shaped using a jigsaw.
Mark out the curve profile to be cut so you know where your heading.
Read the section below on Stretching at the pinch point region. If you have issues where you need every bit of room, stretching will find you another 5 mm (200 thou) and best to do this step now as you have a big lip to assist you. It can be done later but more care is required.
the curve - After marking out the curve profile, use a
jigsaw (select a short length metal cutting blade for 1-3mm
thickness) or you can use a hacksaw blade (note your cutting
through 2 mm of steel). You cannot go too close to the
inside as the inner sheet metal has a different radius than
the outer sheet metal and the jigsaw blade will hit it. I
chose a minimum lip of 10 mm along the pinch point length
and later on the lip is folded back neatly, with the fold
adding to fender rigidity again. Note you will be cutting
through a spot weld or two, and as the weld is a hard-point
the jigsaw has trouble, so for a few mm I used a hacksaw
blade then continued on with the jigsaw.
Hint - On folding the fender over, paint will crack on the edges for sure. Knowing this will happen you can cut a line through the paint on the guard outer edge, so when it chips and cracks it will progress no further than the cut line. I used a Dremmel tool with a thin disc. (Diamond discs are ideal)
Stretching at the pinch point region
A scissor jack is ideal. Using this method can increase fender clearance by another 5 mm. The grey seam in the photo is what is stretched apart. Don't apply too much force when stretching or the fender will deform.
For pretty good rear guard clearance I aim for 315 mm including the stretch. This is measured from the chassis rail - (where the scissor jack base is located) to the inside edge of the guard at the pinch point. The minimum lip of 10 mm, after folding back, ends up about 5 mm, plus the remaining 5 mm being folded inside.
Continued - File, grind or Dremmel tool the cut edges smooth. Apply chassis seam sealant along the fender edge between the 2 panels idealy to waterproof. Fold the fender lip over as best you can, its tough going with 2 metal sheets, and I ended up folding gradually and neatly using a steel hammer.
On 240's they rust at the bottom of the rear fender, I believe its water getting in-between the two panels with no where for water to drain out, so between the two metal sheets, fill / treat properly with sealant.
Prepare surfaces & apply quality paint to inner resist corrosion, E.G. POR 15 - a resin type of paint is very suitable.