DESIGN & ENGINEERING
It was never about creating something that looked like it was imitating the past. It wasn’t about reminiscing about times gone by, it was about Imagining what could’ve been, had Porsche continued down the air-cooled route. We had to build the best driving air cooled 911 ever, one so pure and immersive in its driving experience, it would reward the driver like no other car could.
From the outset the GW 993 would always be a case of function over form.
Creating modern day solutions using modern technology and employing modern day production techniques to tackle historic & generic problems, all in the pursuit of perfection is what Gunther Werks is all about. All this done with a passion that did not distract from the ultimate goal, to deliver a driving experience like no other, & one that whilst modern, retained all the iconic elements the 993 is revered for.
To retain the qualities of the original 993 but to then modernize and enhance and improve would be no easy task.
The 993, like all air cooled 911s, was legendary for its steering feel, but was also famed for its inherent understeer. Through evolution modern Porsches still offer the famed steering feel but no longer suffer from the understeer that came with it.
This was the starting point, the single most defining element of any 911 and where the GW team would start.
In order to tackle this issue, we looked to Porsche and how they tackled the problem back in the 90’s on the most advanced 911’s of the time, the race cars.
The race cars used Porsche’s built in additional front suspension mounting points, these widened the front track to the same width as the rear track, making the car “square”. By squaring the car and implementing the racing suspension setups of the time it made the 90’s race cars handle like no rear engined car had any right to, and all but eliminated the dreaded understeer.
At GW we started from these additional suspension mounting points but using 21st century solutions to tackle 90’s issues. Bespoke GT style uprights designed to our own specific geometry requirements, from these uprights, custom wishbones were hung and used our own multi adjustable tie rods with full rose jointed components all the way giving us the solid base we wanted. This would then be repeated at the rear of the car, where we would then decide on wheel & tire combinations that would tie everything together, and make sure we had a car that drove right.
Working with the best names in the industry we made sure nothing would be compromised. Working with Pirelli to supply the tires we required, and with the experts at JRZ suspension that would make us the 4-way adjustable shocks and custom suspension components specifically for the GW 993 program. All of these had to work with the bespoke Brembo brake solutions that we would be running, including a carbon ceramic option that are massive 380mm front & rear. And these aren’t just any ceramics, these are Brembo CCMR’s, that use unidirectional carbon fiber construction utilizing Formula 1 technology.
Everything was considered, from the car specific suspension mounting points, to the wheel & tire sizes even the difference in sprung & unsprung weight from the donor car we would start with, nothing would be left to chance.
The end result of all this research, is a completely square track front & rear. Unheard of during the air-cooled Porsche era, but something that is common on the modern day cars.
They say power is nothing without control, so once we had designed the cars chassis, we could then focus on the power train. The same meticulous & exacting standards used on the chassis would also be applied to the power train. Working with famed engine builder Jeff Gamroth of Rothsport fame, the GW brief was simple: 4.0 Liters, Naturally Aspirated, air-cooled flat 6 with at least 400BHP, what we got was better 430 Plus BHP at 7800RPM, Jeff surpassed himself.
Running custom ITB’s, with GT3 type ecu controlled intake plenum, all controlled by a dual mapped Motec 600ECU into custom equal length headers leading to an ecu controlled GT3 rear exhaust, all driver operated by a dash mounted sport button, the engine can give you 400bhp of quiet cruising or at press of a button a snarling 425bhp of fury.
But again, it didn’t stop there, it wasn’t just about the power the engine would produce, but how we could get most of that power to the road that mattered. Continuing with the modern day solutions to address the old school tech ethos, and we started with the fan. The fan had not really evolved since the early air-cooled engines that could trace their roots back to the VW Beatle and the 912, so we went out to some Porsche enthusiasts that just happened to design jet turbine blades for aircraft engines as their day jobs. Using the latest technology, they came up with a lightweight fan optimized not only for maximum airflow, but also to reduce drag and power usage, they basically bought the design into the 21st century.
It didn’t stop there, the factory power steering pump, mounted to the engine in the rear and combined with its bracket, front to rear steering hoses and power steering fluid carried within them to the front mounted steering rack, all weighed in at around 70lbs. More importantly for us it used 25bhp from the crank. The same with the air conditioning, the weight of pump, pipes came in at around 60lbs, but more importantly for us used around 20bhp, so between them that’s a loss of 45bhp to the wheels & 130lbs extra weight.
Our solution was simple, we would design an electric hydraulic pump system for the power steering that would sit in the front of the car, and utilize an electric air conditioning system, again sitting at the front of the car. The result, we save 95lbs of weight, most of it from the back of the car, but more importantly both the aircon & power steering solutions would only use 7bhp.
The 38bhp saved would then be able to go through the 6 Speed G50 gearbox with our own specification ratios, single plate clutch and single plate lightened flywheel and onto the carbon clutched 40% locking LSD, to the 335/30/18 rear Pirelli Corsa’s.
Now the mechanicals were complete, we could focus to building the body of the car.