WARNING! If you use the following guide in any way, you do so at your own risk. Although we make every effort to make our guides as accurate as possible we cannot guarantee that they are 100% correct. TorqueVW™ cannot be held liable for faults or third party injury caused by using this guide. If you do not feel confident carrying out the following work get a professional to do it.

I've had an exhaust system sat in my garage for the last 6 months, so i thought it was about time i fitted it.

Saturday morning comes and me and my dad wake up early (6.30) so we can get out to his work to use a ramp to make the job easier. We get there at 7 and get the car straight onto the ramp and hoist the old girl up to have a look at the old standard system that she has on there. This is what it looked like:

All wasn't too bad, so we undid the clamp connecting the back box to the corner section and took the back box off, this was easy coz the backbox was only put on there a month ago due to the old box falling off while i drove along lol.

After loosening the clamp, unhook the three exhaust rubbers in the pictures below and slide the back box out (this may take some persuading with a hammer and moving from side to side, but i does come out in the end).

Next we decided how we were going to get the exhaust mani and down pipe out, as the hole between the bulk head and the subframe was too small to get the centre silencer or the exhaust mani itself through, so we cut through the down pipe where marked on the pic below.

once the down pipe was cut we removed the rest of the exhaust system by just unhooking the last rubber (pictured below) and gentley lowering the rest down.

Next we lowered the ramp to gain access to the engine bay and started to take off the top half of the inlet mani (16v) to gain better access to the exhaust mani.

The Inlet is held on by 5 bolts to the lower half of the mani, 7 bolt at the back that hold it to the head using two brackets, one wiring conector on the throttle body, an air pipe on the right hand rear, and the main boot on the throttle body. After all these are undone the top half og the mani will come right off and be placed out of the way for now.

This leaves loads of room to undo the fiddley exhaust mani bolts, this was easy for me as i put all new studs and bolt in when i put my newly reconned head in a month or so ago. one undone just left the exhaust mani and whats left of the down pipe up and out past the engine.

Heres the mani and down pipe after it was lifted out, you can see where we cut it here.

Here is what you are left with:

Next, because my 4branch is mild steel i couldn't heat wrap it because moisture would get inside the heat wrap and rust the mani out from inside, so i have to cover the steering wrack with a heat proof material (which can be bought from www.rallydesign.co.uk) which looks like this:

Next we slid the 4 branch in from the top, took a little bit of force and wiggling, but went in easier then i thought it was going to, the just put some new exhaust gaskets in and do up the 8 bolts connecting the mani to the head. should look like this:

Pic from under the car:

And then bolt the top half of the Inlet mani bacl on in the reverse you took it off.

Next we got the link pipe and tightened the clamp connecting the link pipe to the 4 branch.

Next we hung the back box using 3 new exhaust rubbers and joined up the corner section of the system (this will make sense in a sec) and hung the corner section using the 4th exhaust rubber so they were both in place (not tightened up).

Because i have used a flexi link pipe to connect the 4branch to the centre section the centre section is now too long, so we measured up the centre section with the rest of the system which was on the car and cut it to size. Then just clamped up the centre section to the flexi link pipe.

Next to get the right position of the back box you need to twist the corner section and the back box so the pipe that goes over the rear beam doesn't hit it, this takes some time and fiddling around, tightening and loosening, but we got there in the end.

Finally, to get the pipe of the back box to sit where i wanted in the bumper recess i needed to undo the bolt holding the bracket of the rear exhaust rubber and twist it round so it pulled the exhast across (this bracket).

Thats it, all on and not blowing (thank god), heres what it looks like now.

Stretched tyres have caused a bit of controversy of late but if you follow our 'stretched rubber' guide you can get that killer stance but safely. Stretching rubber is safe as long as you're not daft!

Most people consider stretching as quite a new trend but in fact, it all began in Japan where they call it 'Hapari'. Drifters used stretched tyres because less sidewall flex was generated, allowing to break traction easier. Also, because of the reduced sidewall flex a smoother transition from left drift to right drift can be created.

So if it is safe to run stretched rubber on a drift car doing over 100 mph on a track then it'll be fine on a modified Volkswagen. Please keep in mind that you are more likely to break traction so take extra care. Also, remember to up your tyre pressure all round usually by about 6 – 8 psi. use your common sense and you'll be safe.

To get more advise, if you are still unsure try www.wheel-whores.com and www.toyo.co.uk have some very helpful width guidelines. Even company's like www.rimstyle.com will supply your new rims with stretched tyres already fitted so you haven't got the headache of trying to find a garage that will do it for you.

We have also tracked down the famous 'Banden' tyre stretch calculator, it's been translated poorly but you'll get the idea. Download tyre Stretch Calculator.

The PCD defines the spacing of the bolts that attach the wheel to the hub of your car. You can get 3 stud, 4 stud, 5 stud and even 6 stud alloy wheels. The more powerful the car the more studs the wheels tend to have. Just because you have a car with a 4 stud hub doesn’t mean that any 4 stud alloy will fit. It’s never that easy. Different manufacturers use different PCD’s.

The diagram below shows how a circle can be drawn with its circumference passing through the centre of every bolt. The diameter of this circle is the Pitch Circle Diameter. As you can see it’s possible to have two 4 stud alloys with the bolts spaced differently to give a different PCD.

So how do you measure the PCD for your car? An example would be measurement (A) below is 100mm resulting in a Stud Pattern or P.C.D of 4x100 or measurement (B) below is 108mm resulting in a Stud Pattern or P.C.D of 4x108.

If the below were 5 stud the Stud Pattern or P.C.D would be 5x100 and 5x108

The Offset (ET) dimension of your wheel is the distance between the centerline of your rim and the surface where the alloy contacts the hub. If the offset is incorrect your wheel may protrude from the wheel arch (which can look cool, but is illegal) or on the other hand it may sit deep in the arch and look crap. Combine this with the wrong rim width and you could end up with a wheel that rubs the inside of your arch and reduces your turning circle.

Even if you buy new wheels that have the same PCD and offset as your old ones, it doesn’t necessarily mean that they will fit. The centre bore of the wheel and hub must match to ensure correct centralisation of the wheel and the spokes design has to allow enough clearance for your brake calipers.

Then once you have decided on a style of wheel a load of questions are thrown at you, “What size are you after? And what profile tyres would you like? Do you know what offset you need? What PCD do you require?”

Often the response will be, “Errrrm?” So what do you need to know?

Let’s start with wheel diameter and tyre profile. The car manufacture has designed and set up your car for the wheel and tyre combination supplied with it. Increasing or decreasing the overall wheel diameter (wheel with tyre on) will affect the following:

Speed reading

Acceleration and top speed

Gearing

Ground Clearance

For example, if you take a 1p piece and move it along a table for one complete revolution it won’t travel as far as a 2p piece doing the same thing. This is due to its smaller diameter and circumference compared to the 2p piece. If you imagine a car designed with wheels the size of 1p pieces and you drove it using the tachometer and held it at 1000rpm for one minute you would travel a distance of 1000 times the circumference of a 1p piece. If you did the same thing in the same car but instead had 2p pieces fitted, the car would travel 1000 times the larger circumference of the 2p piece (i.e. further), but in the same time. As speed is equal to distance travelled divided by the time taken, the car with 2p piece size wheels was travelling faster, however the cars tacho and speedo will have been telling the driver that he was driving at the same speed as with the 1p pieces fitted! This is obviously not true.

That rather long winded explanation is trying to say that if you buy larger diameter wheels then you need to fit lower profile tyres to them such that you maintain the overall tyre diameter that the speedo is calibrated for. If you don’t do this your car won’t be displaying the correct speed information. Any good retailer should be able to advise you on what wheel diameter and tyre combinations will work on your car to prevent any re-calibration being needed. However if you want to know how to do the calculations yourself then you need to understand the information displayed on the side of tyres. Tyre size is designated by three numbers as shown below. The other numbers and letters are used to describe other important characteristics of the tyre such as the maximum speed they are designed for and the max load for the tyre. See the tables at the bottom of this guide for details of what the different values mean.

If your wheel had this tyre fitted you could calculate the total diameter by doing the following:

1. Multiply the first number (tyre width) by the second number (tyre height expressed as a percentage of the tyre width), then multiply this figure by 0.01 to give you the height of the tyre wall in millimetres.

    

   205 x 40 x 0.01 = Tyre wall height in mm = 82mm

    

2. Take this number and multiply it by two (this is to take into account top and bottom tyre walls) and divide it by 25.4. This has now converted the dimension from millimetres to inches. Add this to the last of the three numbers and you have the total diameter (wheel plus tyre) in inches.

((82 x 2) ÷ 25.4) + 17 = Total diameter in inches = 20.2 inches

So if you get a wider tread alloy of the same diameter as the original wheel, you will need a lower profile tyre to maintain the same overall diameter.

e.g. You could change a 185/55R15 for a 195/50R15. The first would give an overall diameter of 23 inches and the second a diameter of 22.7 inches. This is a difference of less than 2%, meaning that your speedo reading still has reasonable accuracy. If the difference is greater than 3% then you need to consider re-calibrating.

If you want a larger diameter alloy then you may need to look at different wheel width and lower tyre profile. If you want to go from 15 inch wheels with 185/55R15 tyres fitted as standard to 17inch wheels then you could go for 205/40R17. This would give an overall diameter of 23.5 inches compared to 23 inches, a difference of 2%.

There are other things to take into consideration when choosing a wheel, as well as the diameter. Some of these being:

• Will the wheel and tyre combination fit in the wheel arch?
• Will the new wheel foul your brake discs and callipers?
• How many studs does your wheel require and with what Pitch Circle Diameter (PCD)?
• What Offset do you require, also expressed as ET (Einpresstieffe)?

However you’ll have to wait until our next guide to find out more about that…...