the Apexi Twin Chamber, can stand boost for about 2.0 bar...
difference between AVCR and profec B.... I dunno le...
hahaha...
I get from net is:
Features
Apexi AVC-R
The AVC-R also uses a highly durable, fast action solenoid valve to physically control the boost . The valve movement (Boost Duty Cycle) can also be modified. Raising the duty cycle increases boost response, while lowering the duty cycle will slow boost response. This feature allows boost response adjustment for varying turbo sizes. Since larger turbos take longer to spool up ( bad low end response) the duty cycle should be raised under lower RPM's for better response. The opposite should be done for smaller turbo's ( excellent low - mid range response, but limited top end power.) A'PEXi engineers address this issue by including extra menus for RPM based boost control. Drag racers may want to utilize the Gear based boost control function. Aside from the basic functions above, the AVC-R has a Start Duty Setting (allows the boost to momentarily overshoot according to gear).
The AVC-R also includes a Scramble Boost function which allows the user to momentarily raise or lower the boost level at the push of a button. Raising the boost level is commonly used when an extra burst of power is needed (ex. entering a freeway). This feature can also be used in drag racing. The driver can set the main boost level to a low setting for maximum traction then, once full traction is achieved, the scramble boost can allow the vehicle to boost full power.
Boost Controller: GReddy PRofec-B
PRofec stands for Pressure Offensive Controller. What that means we're not really sure, and we don't care. The PRofec-B is really good. GReddy's "basic" model features a dual solenoid design similar to the Blitz SBC i-D. The solenoid assembly is somewhat bulky, but mounts easily enough in the engine compartment. An additional pressure signal must be brought to the back of the control unit in the cabin. Our tester came housed in a translucent blue case, which lets you see all the electronic bits inside. When lit up at night, it looks like a cross between a UFO and a holiday ornament. Basic black is available for a few bucks more.
Where the PRofec-A must be trained in the ways of your turbo, the B model comes out of the box smart. GReddy specifically recommends this unit for sequential cars and problem cases. Straight-away boost is responsive, though further tuning can be made with the balance dial. High and low boost each get their own dial, all of which normally sit flush, and pop out for adjustment. Toggling between high and low boost is accomplished either by the mode button on the control unit, or through the use of GReddy's optional wireless remote switching system. Mount it on your steering wheel, shifter, key chain or girlfriend.
Controller: GReddy PRofec-B
Pro: Super simple, works great.
Con: Sensitive knobs.
Cost: $420 in black, $399 in blue, remote switch: $128.
Source:
GReddy Performance Products Inc.
(949) 588-8300
www.greddy.com
Aesthetics: Looks like a Xmas tree ornament.
Ease of installation: Yes.
Clarity of instructions: Fine. Available on Web site.
Features: High, low boost, adjustable response.
Performance: Grrrreat!
