5.0 Mustang & Super FordsProject Vehicles
Castrol Syntec Top Car Challenge Buildup Part 3 - Topped Off
Bigger Boost And A Clutch Swap Round Out Prep Tasks For Our Top Car Shelby
As we stated in the first article in our series on the 2010 Castrol Syntec Top Car Challenge ("Dangerous Drop Top," Sept '10, p. 76), we definitely learned a lot last year in the annual performance/endurance shootout that pits a Mustang flying 5.0's colors against five other rides (and their owners) representing Source Interlink Media's importcentric mags-Eurotuner, Super Street, Import Tuner, Modified Magazine and Honda Tuner. We're on a mission to improve on the fourth-place finish that Ron Cooper scored at the '09 Challenge with his supercharged '94 Cobra. To do this, Carlos Cortez and his '07 Shelby GT500 stepped up as our players for 2010.
We're putting Carlos' steed through a battery of buildups to ensure it will be ready to outperform the imports when the Challenge begins. The on-track tests are quarter-mile (e.t.), acceleration (0 to 60 mph), braking (80 to 0 mph), and-a crowd-favorite-the road-course showdown (lap time), and we decided to use a Shelby GT500 for its factory-borne power and improved handling over standard Mustang GTs. However, based on previous research with Mustangs, we know a good 'Stang can always be made better with the proper measures.
For Carlos' ride, a complete suspension makeover was performed using race-proven pieces from Eibach Springs, Maximum Motorsports, and Nitto Tire ("Maxed Out," Oct '10, p. 64). The new pieces replace previously installed hardware that brought the Shelby down some (lowered), but wasn't quite ready for the hard abuse our entry will endure during the contest.
Once our 'Stang's handling was dialed in, it was time for us to step up the Pony's performance program a bit. As we noted in the introductory report, our Top-Car contender is motivated by Ford's mighty Four-Valve, 5.4-liter engine and topped with Lysholm's enormous 3.3-liter Twin Screw supercharger.
With a VP Racing Fuels C-16 tune, the Shelby puts down 694.68 horses at the rear wheels, and 657.64 lb-ft of gut-turning torque, which we feel is plenty enough to place us among the top dogs at Top Car.
The Challenge is an event where contestants lay every ounce of their cars' performance on the line-especially horsepower-which is measured on the SuperFlow chassis dyno at K&N Performance in Riverside, California. While several performance criteria are evaluated in the Top Car Challenge, rear-wheel horsepower (unofficially) is the big deal in this contest.
Be it domestic or import, big steam ranks high when it comes to determining a street car's level of prowess. So with our mindset on big steam, we added a few cool hop-up goodies to Carlos' Shelby GT500.
The showstopper in our new-parts collection is a 3.25-inch supercharger pulley, which replaces the 4.0-inch Lysholm pulley. The reduced diameter increases the big blower's boost output by more than 5 psi, and we hope it will put our entry in front of the others when it's time to tally up its rear-wheel ponies on the dyno.
In the driveline department is the all-new twin-disc Dyad clutch system from Centerforce (PN 04114805). At 10.5 inches in diameter, the Dyad is a big step up from a Shelby's factory clutch package.
We understand the move was made in an effort to make pedal-effort somewhat minimal, but with the cars weighing 4,000-plus pounds and with the huge amount of torque GT500s can potentially create, the small clutch unit really doesn't stand much of a chance. The larger-diameter Centerforce has more surface area, friction coefficient, and a greater clamp-load capacity than the factory piece. These two qualities are keys to Dyad's overall effectiveness at moving as much of the Shelby's power through the drivetrain as possible.
It's show time, fellas! Take a close look at this report, and then look elsewhere in this issue to learn details of how our Shelby GT500 performed at the 2010 Castrol Syntec Top Car Challenge. And, if you haven't already done so, cast your peoples' choice vote for our entry on the website (www.syntectopcarchallenge.com).
B&D Racing of Van Nuys, California, is well versed in power improving Shelby GT500s, S197 GTs, and all-other late-model Mustangs. The shop's lead technician, Mason "Mase" Rowland, took care of the adding the upgrade pieces on Carlos' ride and the following photos detail these key components.
On The Dyno
We didn't think it was wise to immediately jump on the new clutch. Centerforce recommends putting 250 miles of shifting-intense (street) driving on the Dyad twin-disc before making WOT blasts. The numbers in the chart are results from a previous dyno test (on a Dynojet chassis dyno), in which our Challenge 'Stang still had its stock clutch and driveshaft, but was set up with the same 3.25-inch blower pulley, C-16 fuel, and Lysholm/SCT tune that were in place for the event.