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5 Easy Bolt-On Upgrades for a 2014 Shelby GT500 Mustang
Simple Snake Mods: The 5 easy bolt-on mods that took a bone-stock 2014 Shelby GT500 to 683 hp at the wheels
If there is one way you are guaranteed to end up with a fast car, it is to start off with a faster one. It’s much easier to make a fast car faster than to make a slow car fast. We decided to put the idea to the test and apply it towards one of the fastest horses to ever roll off the assembly line, the snake-bitten 2014 Shelby GT500. With the massive 5.8L supercharged four-valve modular pumping out 662 hp at a moment’s notice, the Shelby GT500 is anything but slow. It’s an example of modern hot rod engineering at its finest, but there’s always room for improvement. We decided to make it our mission to see how much power we could squeeze out of the GT500 with just a handful of easy bolt-on mods that any Shelby owner could undertake in his or her garage.
We started with a stock 2014 Shelby GT500 and headed to the experts in all things Mustang at GTR High Performance in Rancho Cucamonga, California. These guys are no strangers to building some of the coolest Stangs around, so we knew they would be able to make the GT500 really scream. We hooked the car up to the Dynojet dynamometer to get our baseline numbers. In stock trim, the Shelby spun the rollers to the tune of 565 hp at 6,600 rpm with the factory supercharger putting out 12.45 pounds of boost. Our peak torque came in at 574 lb-ft of torque.
Follow along as we walk you through building serious power for your Shelby GT500 with a few simple bolt-ons and a little fine tuning.
Once we had our baseline test out of the way, the guys at GTR went to work removing the factory exhaust in favor of a 3-inch JBA stainless steel cat-back exhaust system. A quick comparison of the stock cat-back exhaust and the 3-inch JBA exhaust reveals a less restrictive exhaust system in favor of the JBA pipes. With the factory exhaust out of the way, Ricardo Topete and Pedro Pasoldan quickly bolted in the free-flowing JBA kit with the supplied clamping hardware.
With the car buttoned up, it was strapped to the dyno again to see how much power we picked up. Topete spun the rollers with the GT500 screaming and laid down 603 hp at 6,300 rpm with 12.34 pounds of boost. This time the GT500 saw a peak torque of 625 lb-ft. Not too shabby for a simple cat-back install.
With a high-flowing exhaust netting us more than a few extra ponies, we decided to turn our attention to the induction side of the Shelby. There really was only one way to go if we wanted to make the most of our modifications, so we ordered up a JLT cold air intake to make sure the big 5.8L four-valve engine was getting adequate air to fill its lungs. We decided to install it with the stock throttle-body for this phase of the build. Topete uploaded a custom Kurgan Motorsports calibration tune via an SCT tuner and rolled the Shelby back on the rollers for the moment of truth.
We’d be lying if we said we weren’t giddy at the fact that the GT500 roared on the rollers and managed to produce 621 hp at 6,400 rpm while generating 12.78 pounds of boost. Our torque gains spiked up to 641.45 lb-ft. We picked up 56 rwhp over our stock baseline run, but we were only just getting warmed up.
This time we pulled out the stops and ditched the factory throttle-body in favor of the much larger Ford Racing Performance Parts Super Cobra Jet oval throttle-body as well as another Kurgan Motorsports SCT calibration tune. The Super Cobra Jet throttle-body comes in at a gargantuan 148 by 65 mm and flows 1,797 cfm to allow the big 5.8L to push the limits of power and performance. So how much gain did we see on the dyno? Phase 3 of our bolt-on upgrades netted us 648.25 hp at 6,460 rpm, while the supercharger boosted up to 14.64 pounds. Our peak torque only climbed by about 5 lb-ft, but we were still pretty impressed to see an 83hp gain over our stock baseline with fairly simple bolt-on mods.
While we could have easily left well enough alone, we knew we’d be leaving plenty of power potential on the table by not swapping the stock supercharger pulley out for a smaller-diameter pulley to increase the boost our Shelby was seeing. We decided to install a 2.4-inch VMP Tuning supercharger pulley on our GT500’s stock supercharger. The VMP pulley features a black finish for the stealth stock look and is made of high-tensile strength carbon steel to ensure durability while pushing the boost limits of the factory supercharger.
This 2.4-inch diameter pulley increased the boost up to 16.8 psi, so of course Topete went ahead and swapped out the spark plugs with a new set of NGK V-Power TR6 spark plugs and loaded another one of Bob Kurgan’s custom tunes via the Live Link tuning software.
With all of our bolt-on mods out of the way, it was the moment of truth. When the dust cleared, we looked at our dyno monitor and saw just what we were looking for: 683.05 hp at 6,250 rpm. The pulley swap made us hit peak horsepower at 16 pounds of boost, while our peak torque tipped the scales at 695.72 lb-ft.
We managed to gain just over 118 hp and 121 lb-ft of torque with just a handful of fairly simple and straightforward bolt-on modifications that any self-respecting weekend warrior can accomplish in his or her own garage. Sure, you’ll have to get the engine tuned, but we think it’s well worth the investment to have a car that can fly down the track at breakneck speeds while still being able to cruise down the highway with ease.