Shelby GT500 Bolt-Ons - Stage Might

The fuel line must be disconnected and the fuel rail removed, all preceded by disconnecting the fuel-injector harnesses and the fuel-pressure-sensor harness on the passenger side. Best not to mess with this fuel stuff on a hot engine, right?

With the lines, harnesses, and bolts out of the way, the rail is easiest removed with the injectors still attached. Be gentle on the injector O-rings-a little wiggling can ease the process.

Next up, the EGR tube must be wrestled off and the EGR valve itself unbolted from the blower.

It's almost time to get at the blower itself, but be advised that there's a vacuum line connected to the back of the supercharger case that's not exactly easily seen. Don't forget to disconnect it, and always treat any vacuum lines tenderly as vacuum leaks can spoil your day.

One other small task is to unbolt and set aside the coolant reservoir so you can get at the serpentine belt tensioner. After you've released it and unlooped the belt from the blower pulley, you can unbolt the tensioner in readiness for swapping on the kit's new idler pulley.

Ten bolts secure the Eaton to the lower manifold. Once out, you can lift off the blower, pack it up, and ship it off to PHP along with the elbow and throttle body for "porting and polishing."

Much of PHP's work on the inlet hardware consists of smoothing off the rough cast-surface finish, and generally making the incoming air's trip as slick as possible.

On the backside of the throttle body, the outlet circumference is radiused to blend more smoothly with the mouth of the blower elbow. Ever wonder just how effective such work is on a throttle body? So did Karl, so they did back-to-back dyno testing with a stock throttle body and found that the smoothed version was good for up to 10 hp at the wheels.

The work inside the elbow and blower-inlet area is much the same, made smooth and with a seamless transition from elbow to blower. Like any form of porting, it's a matter of restraint and fine attention to detail.

PHP's Stage 3 kit's blower pulley is 2.6 inches in effective diameter, carved from billet aluminum, and has a hardened-steel shaft. A stock GT500 pulley is roughly 3 inches in diameter.

As mentioned, the kit also includes a new, larger billet idler pulley for use on the tensioner. This allows retaining the stock serpentine belt.

Be prepared to lose a little coolant when you yank the stock 198-degree thermostat in favor of the kit's 160-degree replacement.