Trying to obtain the correct size of wheel and tyre for a buggy can be a nightmare! In the UK we have little choice without having to use wheel adaptors or redrilled hubs, particularly if you want something different from the norm. To have the correct looking wheels fitted can greatly transform it and increase the “wow” factor, especially if after a lot of research, trial and error, at the end of the day you’ve got it all aesthetically nice and correctly proportioned. Your buggy has to sit right to keep pulling the birds (or guys)! …keep dreaming!!
The style you choose is a matter of personal choice, so when it comes down to looks, checkout the wheel catalogues and just look at other buggies for inspiration.
When buying secondhand or aftermarket non-standard VW wheels for your buggy, you must check the pitch circle diameter (PCD). PCD is the measurement of the diameter of an imaginary line that passes through the centre of the four or five mounting holes.
On buggies with 5 bolt wheels (up to 1967) the PCD is 205mm. This is also shared with some Mercedes models.
On buggies with 4 bolt wheels (after 1967) the PCD is 130mm. This is also shared with some Skodas & Lancia models.
Never try to elongate mounting holes to change the PCD on wheels that almost fit onto the studs.
Interchangeability of wheels requires a lot more than just matching wheel bolt patterns.
The width of rim you can fit depends upon the distance from the wheel centre to the mating surface of the hub; called the inset or outset. Inset is where the mounting surface of the wheel is closer to the road side of the wheel than the centre line. Outset means the mounting surface of the wheel is closer to the hub side of the wheel than the centre line (see diagrams). The offset is the difference between the centreline of the wheel and the plane of the mounting face of the hub; standard VW wheels use a negative offset value, whereby the centreline of the wheel sits inboard of the mounting face. Fitting wider wheels can improve comfort & handling, but don’t go too far; looking at the diagram, you can see that when your VW was designed, they drew an imaginary line through the kingpin axis. The line meets the ground at the bottom centre of the tyre’s tread. It’s called centre point steering; the tyre rotates about the centre point. Move too far from this centre point and the steering becomes twitchy, heavy and is slow to self-centre out of a corner. You’ll also get some bump steer. You will get a positive benefit from fitting slightly wider wheels & tyres; the tyres will not deflect as much, inducing a lower slip angle and therefore more grip and better cornering. If you fit larger diameter wheels the rolling radius of the wheel will change, unless the tyre profile is lowered. This will affect the cars gearing and make the speedo reading inaccurate. Note that both the width and diameter of a wheel is measured from the tyre bead surface and not from the outer rim. Both these sizes are usually quoted in inches.
Standard fit VW wheel bolts are not the correct length to cope with wider wheels. Check the protrusion of the bolt through the wheel – you’re likely to need longer bolts (more expense). Don’t buy them too long – if the bolt protrudes too far inside the hub it may make contact with the internal brake components. Also make sure the shoulder of the bolt is the correct profile. You need to spend time examining the dimension of your current wheel & tyre combinations and accurately measure internal clearances etc to circumvent any interference problems that might arise when changing wheel sizes.
