Golf GTI Endurance Build – Part One
We are never afraid of diving into the deep end and tearing things apart, but this project was bitter-sweet for us as we are such fans of the MK7 in standard or lightly modified form. However, we wouldn’t be Motion Motorsport without that burning desire to turn everything into a race car.
Grab a brew and take a look at our latest project here at Motion Motorsport.
The car is a MK7 Golf GTI Performance and belongs to Luke Handley; a good friend, current racer and valued customer of Motion. It houses the 2.0 TSI engine strapped to a DSG (Direct Shift Gearbox), and being a performance pack model, has 226bhp as appose to 216bhp found in the non-performance models. It is also equipped with a vorderachsquersperre (a.k.a VAQ - which in English means front differential lock). This allows the car to gain traction around the corners. This is the first Golf to be built on the MQB Platform which we are huge fans of.
Here at Motion we never do things by halves - we go to every length when building a car to ensure the best finish and performance possible. We started with a brief from Luke on the championship that the car will be raced in and then set to work!
We aim to build this car into a full endurance spec machine. It needs to complete 2-hour races on a regular basis, but with the reliability and speed to do a 24 hour race if needed.
The series Luke had chosen to run in is the 750MC Club Enduro Championship. A typical race weekend consists of a test/track day, qualifying, followed by a 2-3 hour race. We were aiming for Class B which is a limit of 240hp per tonne. The rest of the regulations are really relaxed which is very exciting as its like an open book and almost anything is possible! The idea here is to build a car capable of being super competitive in both Class B and, in the future, Class A (with a quick change to the engine map) - evolution!
The car will be stripped back to a bare shell where we can start the fabrication process; air jacks, larger fuel cell, seat and steering column positioning and bias adjusting pedal box mounts, as well as a comprehensively designed and built roll cage. We chose Safety Devices for the cage design and install after their work on the M4 we built for Tegiwa last year. We’ll be working closely with them to create an FIA homologated roll cage that suits our build outlines, along with a few chassis modifications while we’re there!
We plan to keep the engine stock internally to aid reliability and simplicity, but with some breathing mods. We also remove any un-needed items such as the A/C pump and HVAC system. The DSG Gearbox will be stripped for inspection and we will install an uprated differential and new clutch packs. Our aim is to then use suspension components from Yellow Speed Racing, Hardrace and Verkline, along with our own fabricated parts. This will allow us to set the cars geometry optimally, maximising the performance and grip levels the MQB Platform can give us.
Now, let’s get to it!
We now have the Golf in the workshop and have made a start on stripping the interior and engine bay to get it ready for Safety Devices. The windows have been removed along with panels, bumpers and trim.
Strip Down And Roll Cage Preparation
The interior has now been pulled apart along with the dashboard, heater box, wiring loom etc (you get the idea!). Weight reduction is well under way with various bits of unneeded bracketry removed including the original seat base frames. This is a long process that requires endless amounts of drilling, grinding and cutting, but is key in shell preparation. This is not only to save weight but it makes the inside a far cleaner and nicer place to be for the driver. It’s also makes it easier for us to clean and maintain!
When it comes to fuel tanks, there is only ever really one option to consider. Used all over the world in a huge amount of championships, we chose ATL (Aero Tec Laboratories). This week, our fuel cell has arrived which will give us a fuel capacity of 120 litres and the ability to fill from a fuel rig, dump churn, tuff jug or normal fuel pump (dependant on the filler head used). In this instance because of the minimum pitstop time in Club Enduro, we’ll be using a vented Tuff Jugg which fills 20L in around 30 seconds to save some un-necessary expense at this stage but easily upgradable in the future.
We need the extra capacity so that we can go the distance during long races and give ourselves a bigger pit stop window with more usable fuel at our disposal. Dave mocked the tank up inside the car and we cut out its new home! All this must be done before the roll cage is fabricated, mainly because of the obvious problems that putting a maze of tubes inside a car creates for actually working on it, but also so we can see where the cage can sit without having the embarrassment of not actually being able to fit a tank in the space we have left.
We have removed the engine and made a start on stripping back all the seams, the bulkhead and chassis legs of seam sealer. It’s a task that requires patience, a heat gun, scraper, wire wheel and huge tub of elbow grease! None the less, it’s absolutely necessary and serves to reduce weight while giving us access to the seams so that we can stitch weld the shell.
Not only did we ask Safety Devices to produce for us an FIA spec roll cage, we also had them work on a few modifications to the floor pan and exhaust tunnel so we could get the drivers seat further back and towards the centre of the car. The exhaust tunnel in the GTI is pretty large with it being an MQB Platform designed to accommodate different drivetrain layouts (dependant on the model produced). Due to this we were unable to position the seat where we would have liked for the purpose of a better weight distribution, so the decision was made to cut away the exhaust tunnel to allow us a more favourable seating position. Although this is something we'd normally do in house, as SD were fitting the FIA seat mounts, it made sense for them to do the exhaust tunnel work whilst the car was in their hands.
The car is now back from Safety Devices and as always, they’ve done a great job, really following the brief we had whilst adhering to all of the relevant homolgation requirements.
It’s now time for us to stitch weld the shell, fabricate airjack mountings, add suspension mount strengthening plates to the rear, change the front strut tops, add various mounting points with weld in bosses and plate any holes that are no longer needed.
Our components have arrived from Yellow Speed Racing which include air jacks and our custom specification coilovers. Dave got straight into the fabrication and has completed the installation of the air jack tubes, as well as making a start on the front top mounts. It’s difficult to gain access to adjustable top mounts on these cars so we have completely cut out the mounting point for the front top mounts. This is to reposition them further back and inwards to allow us to gain more caster and access for quick and easy adjustability.
Along with the long list of jobs at this stage, the pedal box install is complete, the fuel tank box has been finished with mounting points, the rear quarter inner skins have been cut away to allow for filler necks and all of the safety harness mounting points have been drilled and welded. Once we were happy that the car was ready for paint, the painstaking tin tape process begins! We cover all remaining small holes in the shell so that the paint finish is much nicer and prevents water ingress when running in the wet.
The shells paintwork is now complete! We opted for a dark gunmetal grey inside to minimise reflections, which allows the driver to fully focus on the track. We have very lightly stone chipped the underside and arches after taking it back to bare metal, finishing them in gloss white to match the body. Look at the results – they speak for themselves! It’s also always a lovely point in any build to stand back and appreciate the extra time and effort put in.
Before the assembly stage, we need to get the shell heat proofed. Driving a race car flat out for 2 hours is hard work (even more so if you’re cooking like a jacket potato), so anything we can do to keep heat out of the cockpit is essential. Remember we removed the HVAC system? The only form of cooling we have in here is through the window vents and that creates drag which we don’t want. This is why it makes sense to minimise the heat transferred into the car so we don’t have to worry so much about getting it out!
We have applied heatshield to the bulk head and re fitted the exhaust tunnel shielding. The exhaust down pipe has been heat wrapped and wire lock was used to hold it into place and extra heat matting has been added to the base of the fuel tank around the exhaust system.
Part 5 Coming Soon