Much like the volume knob on a high-end stereo receiver, the EVC EZ is ready to rock, so tune in cautiously. There's no mention in the one and a half pages of English instructions about problems using the EZ on cars with minor boost creep, but it sure doesn't seem to like it. To be fair, we've had no boost spiking problems on our externally wastegated test car.
| CONTROLLER: HKS EVC-EZ |
| PRO | CARB legal. Adjustable from inside the cabin. |
| CON | Significant boost spike. |
| COST | $395. Installation kit, $20-135. |
| SOURCE | HKS USA |
| (310) 763-9600 x203 |
| www.hksusa.com |
Aesthetics: Simple and clean.
Ease of Installation: Two wires, three hoses.
Clarity of Instructions: It missed the most important one, "be careful with the dial." Otherwise, fine.
Features: In-cabin adjustable boost. CARB legal.
Performance: Boost control not as good as a ball-valve.
Controller: HKS EVC IV Silver Edition
The HKS EVC is the granddaddy of electronic boost controllers. Many still consider the EVC II to be the best boost controller out there because it's so simple to use, thanks to high and low presets on its face and a knob that lets you manually dial in a third boost level. It would work with both internal and external wastegates if you knew which dip switches to flip around inside. For years it was the only option, because everything else out on the market didn't work.
The EVC IV shares its case size with all the other HKS electronic components back to the original EVC I. It still has the high- and low-boost modes, but now you also get a scramble mode, integrated boost gauge, over-boost alarm and protection feature. The limited edition silver model we're reviewing here incorporates a handy additional Peak/Hold function on the boost gauge. Peak/Hold is key for programming the EVC IV, because like the PRofec A, it tries to take advantage of a fuzzy logic to optimize boost characteristics. Unlike the PRofec though, programming is a pain.
To do anything you must depress some combination of poorly labeled buttons, and do it quickly. Almost every time the dial is turned, it must be calibrated by turning fully to the right or left. Having used the menu-driven interfaces from other companies, operating the EVC feels like a game of Memory. Plus, all four buttons are fairly small, and pretty close to each other, making it easy to hit the wrong one.
There's an optional harness to remotely mount the scramble trigger, which is great. If you're too cheap, just connect a momentary switch between the orange ground and yellow trig wires.