Steve Turner
Former Editor, 5.0 Mustang & Super Fords
February 11, 2006
At cruise night in Anytown, USA, you might mistake this Dark Shadow Gray '03 Cobra for a stocker. But be sure to hear it run before you challenge the car's owner, Brent Riley. You might be surprised. Of course, the nitrous purge out of the Cobra emblem might give you an idea.

Horse Sense: House of Boost is not only a group of friends dedicated to unnatural induction, but it's also a way of life. The HOB Web site ( offers T-shirts and stickers for sale, and perhaps best of all, it also has photos of models with cars-let's call these lovely ladies Boost Babes!

It's a familiar story: Man buys car. Man adds bolt-on modifications. Man loses mind, and goes berserk on his car. We'd love to say it always starts out innocently, but that really isn't true. When the car you start with is the most powerful Mustang Cobra ever sold (so far), we have to think that adding more power is tough to justify to anyone who doesn't understand speed lust. Brent Riley, of Mission, Kansas, was perfectly happy adding ProCharger's base '03-'04 Cobra kit, which easily takes the factory 390hp Cobra into the 500hp range. Let's face it-that's more power than most drivers need in a street car.

Ah, but there's need, and then there's want. Brent began to want a lot more because he was fraternizing with Dorian Comeau of House of Boost. While Dorian's day job is in the tech department at ProCharger, his alter ego at the House of Boost is into taking boost to the next level with wild street combinations. "I just want to show people you can go beyond our [ProCharger's] basic kits and get really creative," Dorian explains. When it comes to Mustang projects, his goal is to show those turbo Supra guys that Mustangs can beat them without becoming all-out race cars.

Now this is a thing of beauty. Replacing the stock supercharger and lower intake/intercooler with Sullivan Performance's Cobra intake cleans up the engine compartment. Up to this point, the long-block has remained stock, but that intake is the gateway for two power adders. Between the Sullivan upper elbow and lower intake is a Nitrous Express wet plate just in case. The headliner is a ProCharger F-1A that blows through a three-core sheetmetal intercooler into the stock throttle body.

House of Boost cars have popped up in several magazines, including the Four-Valve Fox we featured in our Feb. '05 issue ("Cammer Commuter," p. 94). Each of these cars goes beyond the basic bolt-ons we might have on our Mustangs, and refines many aspects of the car with a host of custom touches. It's the kind of car that attracts a crowd-and bozos like us from the magazines. Of course, it's one thing to see the car and the magazine and remark about how cool it is. It's quite another to see these cars on a regular basis, as Brent Riley does. With that kind of peer pressure, he wanted to take his bolt-on Cobra to the house-the House of Boost.

So began the transition from bolt-on to beyond. Brent still wanted to keep his sleeper theme on the outside, but under the hood he took Dorian's suggestions and added a Sullivan Performance intake manifold, which supplanted the factory intercooler. This intake does its best work under big boost and rpm, but the HOB boys decided to build the combination as a counterpoint to positive-displacement screw blower combinations that use nitrous to cool the incendiary air-charge temperatures at high rpm. Instead, Brent added a wet nitrous kit to give the car an extra low-end hit. The kit features a carbureted plate between the Sullivan upper and lower, where the nitrous and 116-octane fuel join the excitement.

We ran into the car with the combination as we described at the massive ProCharger display at the World Ford Challenge. At that point, the crew hoped to put down more than 700 hp to the wheels with the stock long-block. But it happened again-Brent decided he wanted to add cams. He wanted to build one of the quickest IRS cars around, and he didn't want to chance grenading the stock engine. So, out came the engine before the car even hit the dyno.

Now the goal is to build even more power. With some advice from the modular mavens at MV Performance, Dorian put together a slightly warmed-over engine. The plan calls for the heads to receive mild porting and a quartet of Comp cams. The short-block will get coated JE pistons and coated bearings working with the stock rods and crank. Who knows how much power it's going to make now, but Brent will probably soon want even more. One thing's for sure-they will make it with more boost. "The porting will be pretty mild," Dorian explains. "My solution for making more power is just a smaller pulley. I love boost." With that kind of influence, you know how Brent's car went from bolt-on to berserk.

To ensure the 100-shot doesn't lean out Brent's stock engine, the HOB boys built a dedicated fuel system to feed the nitrous kit. The cell is filled with 116-octane race fuel, which is fed to the solenoids through its own pump and regulator. It sounds complex, but the entire nitrous system-window switch, bottle heater, and throttle-position switch-are all activated by one switch in the cockpit.

Setting this combination apart is the Cobra intake manifold from Sullivan Performance (, which features this sleek forward-facing throttle-body mounting. We detailed this intake in our May '05 issue ("Tower of Power," p. 140). Designed for high-rpm or boosted applications, the intake can be run with fuel injection or a carburetor, and versions are also available for 5.4 engines. While the lower intake was designed to mate with '99 Cobra heads, there's enough material to allow porting it to match any Four-Valve intake runner. The lower intake sells for $599, while the optional upper elbow is $299 and the fuel rails are $179. Dorian found the lower was a perfect match for the Terminator heads as well.

5.0 Tech specs
StockEngine Management
StrokeStock EEC V with SCT Flip Chip
StockTuned by MC Racing
281 ciStock w/NGK TR6 spark plugs
Stock Auto Meter
PistonsFront Suspension
Compression RatioAnthony Jones Engineering
8.5:1Control Arms
CamshaftsAnthony Jones Engineering
HeadsQA 1 coilovers
Stock Struts
Sullivan PerformanceCaster/Camber
Throttle BodyUPR
Stock Brakes
Mass AirStock
SCT 2800 Series Blow-ThroughWheels
Power AddersStock
ProCharger F-1A and NitrousTires
Works wet kitStock
InjectorsRear Suspension
55 Lb/HrSprings
Fuel PumpEibach
Two {{{Focus}}} fuel pumps, AeromotiveShocks
Eliminator pump, Aeromotive DigitalBilstein
FMU, and Sullivan PerformanceControl Arms
fuel rails Stock
MAC Pro Chamber H-pipe andStock
Magnaflow after-catTires
TransmissionNitto 316/35-17 Drag Radials
TTC-Tremec T56 six-speed w/ SteedaChassis Stiffening
Tri-Ax and SPEC Stage Ill clutchn/a