2006 Mitsubishi EVO IX - Budget Boost-Up

+8.0HP
+6.0TQ

Exhaust Dynamics

Why
Before purchasing an exhaust, decide which best suits your vehicle. Noise level, construction, piping diameter, weight, appearance, muffler chambering, cat-back or turbo-back are some of the bigger factors to consider. We elected to go with Greddy's Racing Ti-C, featuring 80mm stainless piping, a polished stainless-steel canister and a heat-treated titanium tip. Greddy claims its testing netted a lower-than-94db sound rating, its straight-through design makes more power, and fit and finish are second to none-all without breaking the bank.

Verdict
The Greddy unit sounds awesome when the 4G63 is under duress. However, it can drone a bit at cruising speeds in Fourth gear. The key is to get into Fifth, because from 2,200 to 3,500 rpm the system purrs like a kitten. More sound suppression can be had by installing the included silencer. Drift-Office manned the Dynojet in testing the Ti-C, and the Ti-C and with an English Racing tune, upped the ante to 288 hp-a six-horsepower jump over our gains with just the Buschur filter. Peak output was recorded at 288 hp and 274 lb-ft of torque.

Flash Dance

Flash tuning pays instant dividends on the EVO IX platform. To illustrate this numerically, we flashed the car in stock form and baselined at 266 hp at 20 psi. The flash netted a peak gain of eight hp, which is nothing to sneeze at, but deep in the run where the engine is factory tuned at a stiflingly rich 10:1 air/fuel ratio, English Racing gained an impressive 48 hp by trimming the fuel maps. The English Racing flash also increases rev-limit, adds a valet mode and turns the check engine light (CEL) into a knock warning light, that illuminates when a knock count of three is realized using EvoScan software. The accompanying photo shows the knock counter and other streaming data ready for a dyno pull.

+30.0HP
+25.0TQ

Spoolin' and Droolin'

Why
Boost control is a big savings opportunity for the budget-minded boostaholic. If you plan to keep things reasonable (i.e. stock turbo and stock injectors), and won't be boosting more than an additional five or six pounds, go manual. A whopping 80- to 90-percent savings in cost can be realized.

EVOs have a boost spike at initial spool-up, at which point the turbo tapers boost pressure as the engine progresses through its rev range. "Typically, the boost spike is resultant of the controller being used," says O'Neal. "Manual boost controllers using a ball and spring will spike because of the dynamics involved. Some electronics will mimic the factory spike while others can be used to tune the boost curve relatively flat."

"Boost taper results from the turbocharger running out of breath. A stock EVO's turbo is really too small to make much more than 22 psi at redline without some really aggressive modifications to the turbocharger and intake."

Verdict
A Hallman Pro RX boost controller could be the best $89 ever spent on an EVO. It features a ceramic ball and stiffer spring not offered in other manual boost controllers. And like all Hallman units, it sports a slick aluminum body, easy-to-use adjustment knob and comes in an assortment of colors.

Lucas English dialed-in the Pro RX to 25 peak pounds of pressure, tapering to 19. With the EcuFlash generating conservative air/fuel ratios of 12.2:1 to 12.4:1, Lucas was able to coax 318 hp and 299 lb-ft of torque from the 4G63. That's a 52hp peak gain and a whopping 75hp improvement at 7,100 rpm.

By Evan Griffey

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