Never shy about testing and...
Never shy about testing and modifying brand-new Mustangs, Lethal Performance got down to business with its '11 GT project right way. Doing its thing at Mustang Week with UPR's Jeremy Martorella behind the wheel, the GT posted a 12.33 at 111.71 with only a tune and the off-road exhaust. Unfortunately, they didn't get back to the track after this round of mods, as we went straight into the next phase. Stay tuned for boost.
The moment a new Mustang is announced, the aftermarket wheels start turning. For us, it's one of the most exciting times in magazine land. The anticipation of how the next Mustang will respond to the overtures of speed freaks is at the heart of what we do. As such, when we finally get down to business with a real-world car and a pile of parts, it's quite simply a lot of fun.
When Lethal Performance approached us about covering the buildup of its latest project car-a Grabber Blue '11 GT-it didn't take long to say "yes." We've seen the fearlessness with which the company has approached its previous project cars, particularly the massive overhaul of fresh-off-the-lot GT500s. Knowing the company would dive right into the new 5.0 with the same abandon made it an easy choice.
"We knew the 2011 GT was going to be a success," Lethal Performance's Jared Rosen explained. "From its power rating to its fuel economy to its price, it can't be beat. That basically made it a no-brainer to get one. It also opened the door for us to help develop and test new parts as the motor, fuel system, and many other things had changed from the previous year."
While it would be easy to go nuts on the new Mustang with forced induction, the plan was to show a bit of restraint-at least, initially. As such, Jared formulated a logical package of the typical intake and exhaust bolt-ons for our test. Of course, never one to leave well enough alone, Jared already had a nitrous kit onboard to put the icing on the bolt-on cake. As you'll see from our dyno sidebar, the results were quite impressive for such a modest list of additions.
"The tune itself really helped to improve throttle response; raising the rev limiter over stock allowed us to take advantage of the car's high-rpm powerband. Add a high-flow JLT intake into the mix and you've just made it even that much better," Jared enthused. "Then to gain another 14 rwhp from ditching the cats and going with the Lethal 3-inch off-road X-it put us over 400 rwhp, which is great power for simple bolt-ons."
Quite simply, the latest Mustang is impressive, and we're just getting started with modding these cars.

As soon as Jared picked up...

As soon as Jared picked up Lethal's '11 GT from Weikert Ford in Lake Worth, Florida, he had the car's exhaust measured so Lethal could offer its own 3-inch off-road midpipe (PN LP-2011GTORX: $299). This aluminized-steel, mandrel-bent, X-shaped crossover bolts right to the factory Tri-Ys and after-cat, and eliminates the factory catalytic converters. When you remove the cats, that mandates you flash the car with a custom tune too, or you'll see a Check Engine light.

"...Even after the X-pipe...

"...Even after the X-pipe install, the exhaust still isn't that loud," Jared said. "Magnaflow had the answer to that with its 3-inch competition after-cat. Now the car sounds just like a Mustang should." The answer from Magnaflow was the company's Competition Series after-cat system (PN 15590; $809.97) for the '11 GT. This stainless-steel system features 3-inch tubing and 5-inch mufflers with 4-inch tips. Combined with the Lethal crossover pipe, this system provides a throaty growl during acceleration and a mellow rumble when cruising. Nice.

Another piece of the bolt-on...

Another piece of the bolt-on puzzle was a new one-piece driveshaft from the Driveshaft Shop (PN FDSH22-A; $749.95). This 3.5-inch aluminum 'shaft is rated as capable of handling up to 900 hp without adding any vibration. Besides its durability, it's said to shave 29 pounds of reciprocating mass versus the 48-pound stock driveshaft.

We've been itching to test...

We've been itching to test JLT Performance's cold-air intake for the '11 GT (PN CAI-FMG-11; $349), and main man Jay Tucker was kind enough to send the prototype off his own car for our test. As our deadline approached, he was able to update us with a photo of the production CAI, and it's a beauty. The one-piece unit is available in carbon fiber or painted roto-molded plastic, and features a plastic heat shield to stave off underhood air.

The task started at Power...

The task started at Power by the Hour in Boynton Beach, Florida, where John Tardonia handled the wrench work on the exhaust and driveshaft, which began by unbolting the stock exhaust.

Next up was dropping the hefty...

Next up was dropping the hefty stock driveshaft. Once the driveshaft is free of its bolts, it's suddenly apparent how much weight Ford put behind the transmission.

While it does require swapping...

While it does require swapping on a new pinion flange, the DSS driveshaft is truly a bolt-on affair.

Lethal's X-shape crossover...

Lethal's X-shape crossover bolts right up to the factory Tri-Ys and the stock after-cat, while eliminating the restrictive stock cats.

Magnaflow's full after-cat...

Magnaflow's full after-cat system goes beyond just replacing the mufflers. It replaces the factory pipes from the crossover pipe all the way back. By doing so, it eliminates some of the dimpled restrictions in the factory piping for better flow. Just slip on the crossover pipe and reuse the factory clamps in the front.

Magnaflow's after-cat system...

Magnaflow's after-cat system is available with quieter Street mufflers or louder Competition mufflers. It's no surprise that Lethal chose the robust Competition cans for its project car. These mufflers are much lighter than the stockers, and they slip into place using the factory hangers. It's a really simple install, but having a lift does make it a lot easier.

Seemingly since the dawn of...

Seemingly since the dawn of time, dropping in a direct-replacement K&N air filter (PN 33-2431; $52.95) has been a staple of early bolt-on modifications. Since the S197 era, cold-air intakes have become more popular than just replacing the filter. However, we wanted to see if there was merit in this easiest of additions. Here Lethal's Jared Rosen proves a parts guy can install parts! It turns out the K&N was worth a few ponies.

Part of the JLT is this heat...

Part of the JLT is this heat shield, which attaches using the same fastener locations as the factory airbox. Unfortunately, Lethal had installed its Zex nitrous controller right where the heat-shield base meets the framerail. This conflict meant we had to do without the shield for our testing. Since we were running with the hood up, it wasn't a big issue.

It's simple screwdriver work...

It's simple screwdriver work to swap the mass air electronics into the JLT and clamp the unit into place. The prototype utilized JLT's familiar 110mm mass air housing, but the production unit is a one-piece carbon fiber or plastic unit. Its shape offers a larger diameter and a gentler bend than the stock induction hose. Coupled with the high-flowing conical filter, this unit obviously flows more than the stock cold-air intake.

With Jon Lund doing the tuning...

With Jon Lund doing the tuning work from a remote location over the Internet, Chris Hetzel stepped in as the tuning mediator for our session. He flashed the car with updates to maximize each change we made using a SCT X-Calibrator 3.