For weeks we've had the EVC IV running on our externally wastegated test car with no problems. Installing it on the Eclipse was straightforward; it went in just like the EVC EZ. We could get through the learning procedure just fine. Once a boost level was dialed in however, the EVC just seemed to sit back and watch the show. Boost would build quickly, and just keep on going right past our set point. Peak/Hold recorded only a fraction of the pressure run, which was probably the reason the alarm didn't activate. Luckily, we had good fuel in the car, and it was able to survive the 25 psi of boost. We tried reprogramming, swapping out the harness, even using the actuator from the EVC EZ. All the settings were checked by a number of people. Replacing it on the other car proved the unit works fine. It just didn't like our Eclipse.
HKS as a company has been very aggressive in perusing CARB-exempt status on all its products. This effort is by no means trivial, and we applaud its efforts. Here in California, vehicles are being pulled over more and more often for suspected vehicle code infractions. Bottom line: If your car gets inspected by the state, you want an EO number for every aftermarket part you have. HKS is the only one that offers this security.
| CONTROLLER: HKS EVC IV SILVER EDITION |
| PRO | CARB legal, peak / hold boost gauge. |
| CON | Won't work on a boost creeper. Adjustment dial from hell. |
| COST | $735 silver, $675 std. Installation kit, $20-135. |
| Scramble trigger $80. |
| SOURCE | HKS USA |
| (310) 763-9600 x.203 |
| www.hksusa.com |
Aesthetics: Nice size, clear display, meaningless button labels, totally lame dial.
Ease of Installation: Yes.
Clarity of Instructions: Japanese book gets 62 pages. English book gets 5. We must be missing something.
Features: Low, high and scramble boost settings. Boost gauge (peak/hold on silver model). Overboost warning and protection. CARB legal. Adaptive control.
Performance: Needs to be manually set, then doesn't hold true. Scramble works well, though.
Controller: Ball Valve
Here it is, the hardware store homebrew that could. DSS' manual boost controller is a simple ball-spring system that delays pressure from getting to the wastegate. An adjustable spring holds the ball bearing against a seat, blocking off pressure from reaching the diaphragm. Once the spring is overcome by boost pressure, most of the air makes its way to the actuator, while a bit is allowed to bleed off to atmosphere. This bleed is necessary, as once you're back out of boost, you don't want the ball-spring to act as a check valve and hold the wastegate open. If you're handy and want to build your own, try these numbers to start: 0.065-inch bleed, 0.375-inch ball, 3 lb/in spring.