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2003 Infiniti G35 - Power Pages

The Dyno Doesn't Lie

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Dynamometer: Raceline 224X Dynjoet


The Infiniti G35 sedan is a capable performance car that willingly offers both sport and luxury rolled into one package. The G sports a front-midship layout that puts the engine over the front axle for better weight distribution (52/48 front/rear weight bias) and a 3.5L V-6 powerplant that produces a factory rated 260 hp and 260 lb-ft of torque. The VQ35DE has built a reputation as a true “workhorse” that has been praised by both previous and current owners to run reliably over 200K miles and simple to modify with aftermarket parts. With a current resale value for a ’03 sedan ranging from $5,000 to $7,000, the G35 has remained among one of the more popular used cars on the market.

As with any older vehicle, periodic maintenance is crucial to keeping it in good running condition. With over 155K on the odometer, we had our G35 serviced with a routine inspection of all fluids, and replaced the spark plugs before we began our testing. Besides the usual problems you would find on a car that’s over 9 years old, including oil consumption problems found on the earlier-model VQ35DE and a set of balding tires, the vehicle and engine was in good condition.

With the car strapped to the dyno, we made a series of pulls only to discover peak numbers were a bit lower than the average G35. We attributed this loss in power due to the larger-than-factory-sized 19-inch wheels and 87-octane fuel the owner had graciously filled in the car prior to our test. We addressed the lower grade fuel issue with a bottle of high-octane additive prior to our baseline run, which helped to quell the low and high rpm detonations the car was previously experiencing with the low-grade fuel.

Tanabe Medalion Touring Exhaust with optional Y-pipe

Exhaust, (optional) Y-pipe, mid-piping, gaskets, mounting hardware, and instructions

10, 12, and 14mm sockets; 10, 12, and 14mm open-end wrenches; ratchet; extension; crescent wrench; and WD-40

Installation time
70 minutes

The Tanabe Medalion Touring exhaust for the G35 sedan features large 70mm diameter stainless steel piping with a 115mm tip and a straight-through design with no “bottleneck” restrictions on the flanges to ensure a free-flowing design. The exhaust canister uses Advantex, the latest in packing material technology that enables it to achieve high efficiency while maintaining a streetable tone that’s less than 93 dB. We added the optional Tanabe Y-pipe, which eliminates the most restrictive part of the exhaust system found on the factory Infiniti G35 exhaust system’s piping. The Y-pipe’s 70mm diameter pipe provides additional horsepower gains when used in conjunction with the Tanabe exhaust system to achieve a true cat-back exhaust system and is designed with flex piping to eliminate any shearing or cracking of the pipe due to engine torque.

Due to the Tanabe exhaust and Y-pipe’s three-piece design, we suggest asking for assistance to help speed up the installation process.

Dyno testing the exhaust revealed an increase in power and torque throughout the powerband, with gains of 22 hp and 16 lb-ft of torque at 4,200 rpm over our previous run, along with plenty of gains in the midrange to the top end. Consistent gains of 8 hp and 6 lb-ft of torque were seen from 5,300 to redline over our baseline run.

DC Sports Short Ram Intake

Intake, filter, brackets, nuts and bolts, clamps, Allen and Torx-bit wrench, CARB sticker, and instructions

8, 10, and 12mm socket; 10mm open-end wrench; ratchet; extension; screwdriver; and pliers

Installation time
40 minutes

DC Sport Air Intake System features one-piece aluminum construction that’s polished to a show-quality finish. The kit includes an air filter that requires no oil, therefore eliminating the chance of contaminating the mass airflow sensor, which can result in loss of power and higher fuel consumption. The washable and reusable oil-free air filter features a built-in velocity stack that increases airflow rates. The DC Sports G35 intake kit is 50-state legal and compatible with ’03-06 model vehicles.

When installing the intake, pay close attention to the step-by-step instruction manual provided with the kit. An incorrect installation or a loose intake clamp will cause the vehicle’s MAF sensor to activate “limp mode”, causing the engine to lose power.

The DC Sports intake system increased both horsepower and torque throughout the powerband. Our G35 recorded the largest gains in the top end from 5,500 rpm to redline with a gain of 10 hp and 8 lb-ft of torque.

Berk Technology High Flow Cats

High flow catalytic converters, mounting hardware, and gaskets

10, 12, 14, and 17mm socket; swivel; ratchet; open-end wrenches; extensions; breaker bar; antiseize; and WD-40

Installation time
110 minutes

The Berk Technology High Flow Cats (HFCs) have free-flowing 200-cell metallic catalytic converters that feature TIG-welded construction, stainless steel flanges, and OEM-type gusseted support brackets for quality fitment. Berk Technology provides additional wideband 02 bungs for each exhaust bank for tuning and a built-in 02 simulator fix (primary 02 sensor) to prevent engine CEL’s from triggering and are OBD-II and 49-state compliant. Upon installation we were glad that our G35 did not emit any telltale exhaust fumes that might alert law enforcement to take a closer look under the hood.

Removing the factory catalytic converters requires removing the plastic splatter shield and exhaust brace bar to obtain easier access to one of the three bolts from under the car. Be sure to equip yourself with an abundant supply of extensions, swivel sockets along with different sized ratchets and a breaker bar.

Upon installation, the Berk HFCs gave our G35 a healthy bump in horsepower and torque, along with a slightly more aggressive exhaust tone. The Berk HFCs increased both horsepower and torque throughout the powerband. Our Z made gains of 6 hp and 6 lb-ft of torque at 4,900 rpm, while consistent gains of 7 hp and 6 lb-ft of torque were seen from 5,000 to 7,000 rpm.


What began with a baseline dyno run of 204.4 hp and 197.1 lb-ft of torque was quickly revamped with our final run of 221.9 hp and 219.7 lb-ft of torque. We gained a total of 17.5 hp and 22.6 lb-ft of torque using three bolt-on products. With additional modifications, including ECU tuning and intake manifold mods, we are confident our G35 is capable of eclipsing the 250-whp level in the near future.

Conclusion HP +HP TQ +TQ
Baseline 204.4 197.1
Tanabe Medalion Touring Exhaust with Y-Pipe 210.3 5.9 210.1 13.0
DC Sports Short Ram Air Intake 217.7 7.4 216.9 6.8
Berk Technology High Flow Cats 221.9 4.2 219.7 2.8
Final 221.9 17.5 219.7 22.6

Tanabe Medalion Touring Exhaust $760.00
Tanabe Y-Pipe $590.00
DC Sports Short Ram Air Intake $271.28
Berk Technology High Flow Cats $499.99
Total: $2,121.27

DC Sports
768 S. Turnbull Canyon Rd
City of Industry
CA  91746
Raceline USA
9237 Lower Azusa Rd, Unit L
Temple City
CA  91780
Berk Technology
2135 S. Hathaway Stree
Santa Ana
CA  92705
Tanabe USA
1849 Western Way
CA  90501
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