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BBK Shelby GT500 Throttle Body - Tech Inspection
'08 Shelby GT500 throttle body install
We really hope those of you who own Shelby GT500s have been faithfully reading 5.0 Mustang & Super Fords for the latest news and details on the cool upgrade components available for the special-edition 'Stangs you're fortunate enough to have parked in your driveways (including Editor Steve Turner). While we've pretty much covered all of the elaborate, Shelby-specific engine, drivetrain, suspension, and appearance parts that are currently being sold, testing bolt-on throttle bodies (which, ironically, are a lot simpler than other Shelby products we've told you about) has been uncharted territory... until now.
Installing and evaluating the performance differences (recorded in baseline and post-install tests on a Dynojet chassis dyno) between a mono-blade, 66mm x 160mm piece and BBK Performance's new Power-Plus Twin, a 65mm, dual-blade throttle body for Shelby GT500s (PN 1764; $319), is only one of the agenda items for this edition of Tech Inspection. While the larger, single-blade unit is a major player in the pursuit of achieving maximum power-as evidenced by the stout 662.46 hp and 663.40 lb-ft of torque we recorded during our initial dyno run-the big-mouth 'body has been a minor hindrance to tuning the Shelby's potent combination for smooth idle and good driveability. Our mission with this tech effort is to see whether improved, non-WOT street manners can be tuned into our potent test Shelby using BBK's budget-friendly, CNC-machined, twin-blade throttle body. We also want to see how close the 'Stang can come to it's all-out mono-blade performance on the dyno once the piece with two holes is in place.
As you'll see in the small assortment of photos, the bolt-on aspect of this project is beyond do-it-yourself easy. However, tuning must be handled by an experienced pro using a chassis dyno and the appropriate tuning software, SCT's Advantage III in our case. The results were stock-like driveability and mono-blade-style performance.
As you see here, power and torque with the BBK twin-blade throttle body is pretty much on par with the big steam that our test 'Stang made with a mono-blade 'body attached to its intake. The big difference is in low-rpm street performance and driveability. The BBK piece allows us to easily tune out the low-side "chugging" that is a byproduct of aggressive components like the mono-blade throttle body, and even high-rev camshafts installed in a force-induced engine.
Our final results for this exercise are favorable street manners with only a minimal impact on power. We're sure an actual rear-wheel performance gain will result from installing a Power-Plus Twin on a stock Shelby GT500, which makes it a good bolt-on to consider if you're about to modify or are already making upgrades to make your good 'Stang better.