Upgrading Project GTI to
Improved Touring B Class

Spring 2004

The SCCA Improved Touring category is divided into four classes. The 1993-1997 Golfs (including the GTI with the 2.0 four-cylinder engine) are listed in ITB. This category allows substantial stripping of the car and bolt-on modifications to improve lap times.

It has always been in the plan to upgrade the PhilsTireService.com Team GTI VW to the IT rules but the timeline has been pushed up in order to enter the car in IT for the Charge of the Headlight Brigade 13-hour endurance race at Virginia International Raceway, October 23rd, 2004. The safety equipment rules are identical so we can concentrate on upgrading performance.

Importantly, while the GTI is not typically considered to be a contender in SSC, it is commonly believed that it will be a competitive ITB car...

If there is any doubt about why we are looking forward to upgrading the suspension on Project GTI, this picture should put it to rest.

In Showroom Stock form, soft springs and a lack of roll control result in massive weight transfer to the outside tires - particularly the outside front, which ends up being severely overworked. The car is not as fast as it might be and the tires don't last as long as they would, were the suspension optimized for racing.

The KONI Improved Touring suspension will flatten the car out in the corners and put all four tires to work holding the car on line.

The 13-hour endurance crew is introduced to the fans.

During the upgrade, we will continue to document Project GTI in action but check in here regularly to see what has changed as we prepare for more than half a day of high-speed fun.

Perhaps the most obvious change to Project GTI during the upgrade to IT rules is the removal of the stock interior. The regulations allow removal of essentially all of the carpet, seats, interior panels, headliner, and trim. The dashboard must remain as stock, however.

We elected to retain the door panels as they afford some measure of crushable structure between the driver and the outside world, and because we are leaving the door glass winder mechanisms functional for rally and rallycross competition.

The insulating tar was also removed from much of the passenger compartment floor - a miserable job that is almost a rite of passage for anyone building a stock-bodied racing car.

Before

Evidence of the interior stripping effort is equally striking from the view looking in the rear hatch. While it is legal to remove the seats, it is not permissible to remove any of the brackets that support them.

At the time of construction, it was unclear how much weight Project GTI lost on its diet. The minimum weight for the Mk III Golf in ITB trim is 2350 pounds - 330 pounds less than the minimum in Showroom Stock C (including the driver). It is optimistic to believe that we are likely to make that weight at our current conservative level of preparation.

Before

1/4-inch stainless steel mesh has been added to all front grill openings, to protect the radiator from rocks or other debris that might damage it.

It is legal to run an air dam in Improved Touring but we will stick with the stock lip for the time being.

A number of minor but significant improvements have been made to the cockpit of Project GTI, to enhance safety and control.

A master electrical switch (the red handle in the picture to the right) is accessible from the driver's seat and from outside the car, through the open side window. It shuts off the engine and isolates the battery in the event that emergency response becomes necessary.

The LTB Motorsports quick-release steering wheel hub creates more room for driver changes while also moving the wheel farther toward the rear of the car, affording better wheel placement relative to the shifter and pedals.

The textured aluminum pedal pads (also from LTB Motorsports) are firmly screwed to the throttle, brake, and clutch to provide extra grip and to facilitate heel-and-toe downshifting. This technique allows the driver to slow for a corner while simultaneously matching engine revs to the car's speed for downshifts, by pushing on both the brake and throttle with the right foot.

The struts are relatively simple single-adjustable KONI Sports (commonly referred to as "Yellows") on all four corners, specially valved by KONI's North American race shop to accommodate 500# front and 450# rear springs.

Ride heights are fully adjustable thanks to threaded sleeves on the strut units, and assembly was actually easier than with original equipment parts - no spring compressor needed.

A large-diameter rear anti-roll bar (ARB) was also installed and the stock front bar will be removed, to replace the safe-but-slow understeer of the stock VW with an appropriate amount of oversteer - that is faster but requires quick hands to manage.

You immediately notice the change in stance of the Mk III GTI with the KONI suspension installed. It actually looks a little bit like a racing car now.

The front end of the car is actually still a little too low, given common wisdom about the impact of lower control arm inclination on the roll centers of the MacPherson strut front suspension on these cars. The fastest Mk II VWs running in ITB tend to look nose-high for this reason and additional testing will determine where the settings on the Phil's Tire Service GTI end up.

The track scales at Virginia International Raceway also confirmed that our "diet" netted a 125-pound loss through the removal of seats and interior. Decreased mass makes a race car faster everywhere on the track - on the throttle, braking, and cornering.

The impact of the suspension installation is dramatic once on the track. The car corners flatter and the rear tires are now on the ground, contributing to the grip-generating effort.

In SSC form, the Golf wanted to go straight rather than change direction quickly - a condition known as understeer. The front tires were operating at large steering angles, relative to the direction the driver wanted to go, overworking the tires and slowing the car down.

With the new suspension, the Golf changes direction much more quickly, allowing the driver to get onto the throttle sooner for faster corner exit speeds. Having four tire contact patches improves entry and mid-corner speed as well.

Before

The ITB designation is finally on the doors.

An interesting technical note - these are the 205/55-14 fully treaded Toyo Proxes RA-1 tires purchased from PhilsTireService.com at the beginning of the season.

With attention and careful rotation, they have survived an estimated 9 hours of track time and as they get "old" and the tread blocks wear away, they just seem to get faster and more predictable. Surprisingly, heat cycles don't seem to have any negative impact on their behavior.

Light alloy quick-release hood pins, also from LTB Motorsports, replace the stock interior and safety catch hood release. This allows the crew to get to the engine compartment quickly during pit stops, and saves a little weight at the same time.

It should be noted that one measures more than twice before drilling 1/2" diameter holes in a perfectly good hood.

The long wheel studs and lug nuts from Bildon Motorsports will make pit stops quicker and safer. These allow the mechanics to positively locate the wheel rather than trying to line up the difficult lug bolts that come on VW products. The extra length makes it easy to start the nuts, a second cool set of which will be provided for the tire changer at each corner, since the ones coming off of the car will be heated to several hundred degrees by the brakes.

These studs require the use of a wheel spacer of at least 5mm thickness with stock VW alloy wheels. This pushes the wider 225/50-14 Toyos out closer to the edge of the fenders - the rear, in this case.

Among the improvements tailored specifically for the unusual demands of the 13-hour enduro in October are reflective number panels.

Made of a white reflective vinyl - similar to that used on street signs - the rectangles are essentially invisible during the daylight hours but pop to life when light hits them at night.

This was a busy week that started with the team's lead VW technician, Cameron Conover of import auto specialist der Wagen Haus (Greensboro, NC) putting in some overtime. Conover replaced the front suspension uprights, hubs, bearings, and steering tie rods with more parts out of Bildon Motorsports stock. None of these parts were worn out but were replaced in the interest of absolute reliability for the upcoming endurance race. The parts that came off will serve as spares for the event.

Project GTI then went back to Chris Schimmel at Competition Cages for a new seat mounting system and new brackets for the window net.

The original seat mount was a sliding frame assembly that rode in the stock guides. It would have been perfect for street use but was both too high and too heavy for racing. Schimmel fabricated a tubular frame welded to the tunnel and inside rocker panel, to which were bolted aftermarket sliding rails, aluminum side brackets (replacing heavier steel versions), and a Recaro seat that will accommodate drivers of different sizes for the enduro.

While that work was going on, the last of the interior floor sound insulation was removed and the front half of the passenger compartment was repainted.

This light pod from the vastly experienced Northwest VW rally team Hartmann Motorsport mounts four 100 watt driving lights, to make it possible to run flat-out after dark during the VIR 13-hour enduro.

The system mounts with two 1/4 turn fasteners, a locating pin in the front of the hood, tabs on top of the radiator support, and two electrical plugs, allowing the crew to install it quickly during a fuel stop.

Improved Touring rules require that the glass moonroof that comes in almost all MkIII GTIs be removed and the hole covered by a piece of sheet steel at least as thick as the stock roof.

We had a piece of sheetmetal cut to the necessary size and shape, and punched with 1/8" holes around the periphery by a local roofing shop. This was installed with steel pop rivets and sealant and painted black to replicate the look of the original tinted glass panel.

Isaac, LLC Photo

All of our hard work updating the Golf to ITB specifications and preparing it for the rigors of a long race paid off on October 23rd, when Greg Amy, Evan Webb, Scott Giles, Kirk Knestis, and a team of talented volunteers took home a class victory in the Charge of the Headlight Brigade 13 Hour enduro.

The car wasn't even cooled down when the team started planning for next year, including lively discussion about which mechanical updates should happen next. Stay tuned here for Phase III of Project GTI, as additional tweaks are considered, planned, and executed:

>> Transmission - lower final drive, limited slip differential, maintenance rebuild, and ring-gear bolt kit

>> Engine - IT-spec rebuild with raised compression, replacement of service parts, and optimization of internal parts (balancing and blueprinting)

>> Intake and Exhaust - street-legal exhaust system with muffler and race-spec catalytic converter, optimized engine management chip

>> Suspension - additional adjustable rear antiroll bar, revised spring rates and alignment, wheel spacers, and camber plates

>> Cockpit - upgraded instrumentation, improved mirrors, and a driver's footwell plate with dead pedal rest

>> Brakes - removal of all ABS system hardware, replumbing of hard lines, and addition of a balance proportioning valve

Last updated 1 January, 2005
All photos Kirk Knestis unless otherwise noted

Project GTI is headquartered in Greensboro, NC