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Open Road Racing
our Porsche 928 - Part 2
by Susan Kirby & Marc Thomas of DEVEK Performance.

A good example is when we were first investigating competitive suspension kits and used a progressive spring on the front and moved the old front springs to the rear. Once underway, we entered the first high-speed sweeper and felt the 928 undergo an unusual roll transition with a springy rear end. We realised that progressive front springs made for unpredictable "roll" when the 928’s cornering loads increased beyond normal around town/highway driving. Also, rear to front spring ratio was grossly out of proportion. A quick discussion with a few suspension experts, modified front and rear spring rates, and a switch to a standard non-progressive spring eliminated the problems. We have been using that setup on all our DEVEK coilover kits with great success.

Aerodynamic modifications are also necessary to improve stability and reduce the coefficient of drag at speeds over 170mph. The 928 gets some special tape treatment, with the entire front end of the car being masked over. Side mirrors are removed, and a special front air dam installed to prevent air from going underneath the car. We also employ ground effects to minimise drag and maximise downforce. We have also received factory assistance with regards to high-speed aerodynamic stability for the type 928.

As we became more & more comfortable with open road racing, the obvious desire to go faster and faster developed as well. Our 928’s engine went from 5.0 litres to 6.0 litres, then to its current 6.5 litres of displacement, producing 500 hp and 580 lb-ft or torque at the crank. The most amazing feature of our "928 test mule" is that it’s engine now has over 38,000 miles, has exceeded 200 mph over half a dozen times, and is driven every day!

The highest class of Open Road Racing is the Unlimited Class, which is generally reserved for full race cars, some with top speeds in excess of 240 mph! In order for us to compete at that level, we had to make some major modifications to our 928, which we completed in time for the inaugural Big Bend Open Road Race in Ft. Stockton Texas in July, 1998. The addition of a full roll cage, onboard fire system and competition fuel cell allowed us to enter this class for the first time. An added benefit of the Big Bend Open Road Race is that it was a two-way "down & back" race, and we were able to switch driver/navigator between stages. With a finish-line radar speed of 205 miles per hour, we took second place in the highly regarded Unlimited division, competing against many purebred race cars! Not only were we the fastest street legal entrant and the fastest car ever to drive to and from any event, but we posted the fastest finish line radar speed of the event - not too bad for a street car!

This is one aspect of these events that we are particularly proud of - we have driven our car to and from every event. We don’t even own a trailer. With over 140,000 miles on the chassis, we love the fact that we have a car comfortable enough to drive 3,000 miles round trip and post speeds well over 200 mph at these events! Frequently we will drive "back to back" weekends, going from an open road event in Nevada one weekend, then running competitively at Laguna Seca the next weekend.

We are excited every time a new 928 owner comes out for an open road race and would like to see more 928 participants in future events. Someone needs to keep those pesky Mustangs, Corvettes and Vipers in line! If you would like to find out more about open road racing or preparing your 928 for other racing events, please give us a call at DEVEK (650-592-5287) or contact Classic Auto Racing Society (619-440-6043).

Be Safe and Be Fast, in that order, please! - Susan Kirby & Marc Thomas of DEVEK Performance