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      06-29-2008, 08:31 AM   #79
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Drives: '13 S4, '15 Q7
Join Date: Feb 2007
Location: Woodstock, GA

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Originally Posted by NeoE46 View Post
I disagree. The bypass as performed in the video seen herehttp:// is dangerous. It is still relevant because it is representative of the shortcuts taken by the creator with the product.

In order to do what you describe, the blue hose or rear accumulator should have been Tee'd to the front accumulator hose before the first solenoid. This would have given full control to the front solenoid. The way this connection is described in the video explains the limps and problems seen with the initial product. This, in my opinion, was a negligent shortcut and the reason I chose to pass on Vishnu.
I guess I do not see what you are disagreeing with. As you illustrated, the solenoid is bypassed thus putting continuous vacuum to the wastergate actuators (note, as you have shown, the one vacuum line after the solenoids feeds both wastegate actuators). This contionuous vacuum tries to close the actuators and requires the front solenoid to operate at a lower duty cycle (mis-stated earlier) which keeps the DME happy.

And as mentioned, this is not the case with V2 and V3, the vacuum lines are in stock configuration.

However, the mechanical bypass used by V1, JBx and all other piggy backs is not too different from the electronic signal alterations. In either case, the DME is trying to be fooled to get the desired end results. This has always been the case with piggy back systems.

Perhaps the below diagram will illustrate how the vacuum line to the accumulators are fed fromt he same vacuum pump sources. Secondly, it also shows how both solenoids feed both actuators; byapssing one just forces control of both turbos on one solenoid. This is contrast to what you previously alluded that only the rear turbo's actuator was affected which is clearly not the case.

Last edited by scalbert; 06-29-2008 at 10:05 PM.