:: Track Day Preparation ::
Track days are an absolute hoot, and are often all the more fun if you do them in a car you have built yourself. With the ever-worsening British roads and clampdowns on speeding drivers, track days are the only decent opportunity for enthusiasts like ourselves get to give our cars a jolly good shakedown. They are tremendous fun and allow you to explore the limits of your car's handling in relative safety. The key to getting the most out of a track day is preparation and maintenance. The days are not cheap and if you wish your car to look after you and last the day then you need to look after your car. This is especially important for older cars such as the Mk1 & 2 and early Mk3s, many of which are beginning to get rather tired. Of course modern P1s and Evos etc will race round in circles all day without even batting an eyelid, but if you expect your VW to do the same then you will be sorely disappointed...
This article is written to provide a few sensible pointers as to how to look after your car before, during and after a track day. In order to provide some structure to the article we have covered each area of the car in turn, but not necessarily in any order of importance.
:: Wheels & Tyres ::
Before setting-off you need to ensure that your wheels are balanced, otherwise the vibrations you suffer will numb the feedback through the steering wheel and impair your inch-perfect driving. You do not want to start a track day on brand new tyres, as the large tread depth will cause the tyres to overheat. This in turn will eliminate traction and progressive grip. Conversely you need to ensure that there is enough tread left to get you home after a day of serious abuse.
If you have access to a second set of wheels then use them as you can keep a worn set of tyres on the spares and change the wheels over at the circuit and not have to worry about having bald tyres for the journey home. Another reason for using spare wheels on a track day is to protect your favourite (and possibly expensive) wheels from damage and corrosion caused by brake dust. The brakes take a hammering and will coat your wheels with extremely hot brake dust, which can eat into alloy wheel lacquer and lead to corrosion. The excessive heat generated by the brakes can also permanently discolour the wheel alloy. Before attending a track day you should carry out a visual inspection of the tyres to ensure they are in good condition. Check for cracking of the tread and tears in the tyre sidewall. The last thing you want is a blow-out at 80mph. If you are feeling really hardcore, you could take a set of slicks with you, but be warned; some track day organisers do not allow them and they will also put some serious stresses on your car. You will also find that the cornering forces you are able to generate with slicks will require you to fit a baffled sump in order to prevent oil surge.
At the moment the Matey-Matey team favour Yokohama A539s as they give good grip, are inexpensive and wear well. Note that the more complex the tread pattern and the smaller the islands of rubber between the tread the more likely you are to rip chunks of tread off the tyre with hard driving.
Before going out onto the track ensure that you check the torque of all the wheel bolts and continue to do so throughout the day. When at the track, your main concern is to fine tune the tyre pressures. As you abuse the tyres on the track they will get hot and the pressures will rise so you will want to knock them down a bit to compensate (assuming they were set correctly in the first place). The best procedure for this is to do one track session and get the tyres nice and warm, then look carefully at the scuffing on the tread of the tyres. If the scuffing does not extend up to the edge of the tread then you need to lower the pressure by a couple of psi and if the scuffing extends onto the sidewalls then the tyres are too soft and require some more air. You need to consider things like the overall weight and weight distribution of the car (the more weight the more air is required) as well as the dynamics of the track.
The outside front wheel of a front drive car will do the most work and so get the hottest. As a result its cold pressure should be slightly lower than the other tyres. The more air you have in the tyre the stiffer you make the sidewall and so the more responsive the car is. This needs to be balanced with maintaining a flat tyre foot print. Low profile tyres have small (and thus stronger) sidewalls and so require less air than higher profile tyres as they will roll off the rim less. A point to note is that it is important to have the correct suspension geometry set up. Because the Golf/Corrado/Jetta front suspension allows you to adjust the camber you must get this set up somewhere which can accurately accommodate this (few places do this). If the geometry is out then you will have wasted any money you have spent on chassis mods, and you are more than likely to overheat the tyres.
At the end of the day remember to reset the tyre pressures once the tyres have cooled down and carry out a quick check to make sure you have enough tread to get home and that the tyres are not beginning to fall apart. It sounds silly but we have seen sets of budget tyres literally fall apart well before the treads has worn down. Do not forget to take a tyre pump or compressor with you. It is all very well letting air out of your tyres to account for hot air expansion but you still need some way of being able to replace the air at the end of the day.
:: Brakes ::
These take a complete hammering on a track day, and if they don't then you are not driving hard enough!
What may seem like good brakes on the road often do not stand up to the rigours of track use without some maintenance. The main problem is brake fade caused by repeated stopping from high speed. You may think you brake hard on the road but I doubt you brake from 80 to 30, 3 times every couple of minutes for half an hour? If you intend to do any track days then we would strongly recommend that you invest in some drilled/grooved discs (on the front) and some decent fast road pads as these are far more resistant to brake fade than the standard items. We would also strongly advise you to use nothing but dot 5.1 brake fluid as dot 4 may boil within a few laps and give you that horrible spongy pedal feel [followed by the brown pant feeling as you plough straight on into a gravel-trap].
Braided lines will improve feedback and so help you control your braking on the limit. Make sure you have plenty of life in your pads and discs before setting off. It is not uncommon to get through an entire (or more) set of pads in a day and worn pads and discs will overheat quickly. It is often wise to take a spare set of pads with you just in case.
Throughout the day you need to keep an eye on the brake wear to ensure that they will have enough life left in them to get you home. At the end of each session you should do at least one cooling down lap to allow the brakes to cool slowly otherwise the discs could warp and or crack as they cool too rapidly. When parking between sessions, do NOT apply the handbrake as the hot rear pads can bind to the discs and then disintegrate when you release the handbrake.
After the day it is always advisable to bleed the brakes fully. The brakes will have got very hot and so the fluid is likely to have boiled slightly causing some sponginess.
:: Gearbox ::
There is not much you can do in the way of routine maintenance to the gearbox before a track day other than to ensure that the oil is topped up and is the correct grade. If the box is old/original I would recommend refilling it with fully synthetic oil and some Slick 50 additive. This will help smooth the changes and reduce any crunching between gears. You will notice the difference on the road as well as the track, especially when the box is cold. A point to note is that quick shifts are not necessarily a good idea for track days. We used a very short shift on the 1900 MK2 020 rod change box only to find that it was changing gear so quickly it was crunching into all five gears [the syncromesh it appeared did not have time to engage].
We quickly ditched this and replaced it with a weighted shift rod, which made a vast improvement and smoothed the shift so much that on the limit, mid-corner shifting became possible. Try to do this with a notchy box and you will unsettle the car and end up pointing the wrong way or bouncing off into the undergrowth.