Failsafe with HKS EVC 6
 

Hi all ...

I want to know how exactly to wire the failsafe of the hfs3 to work with an ebc using a stepper motor for boost control ( evc 6 in my case) ... With external WGs

The manual calls for the use of a 3 way MAC valve, but stops short of explaining exactly how ...

Do you set it (MAC valve) to divert the boost referance hose going into the "0" port?
Or set it to disturb (block) the actuator signal hose to the waste-gates "port 1"

My aim is to go down to spring boost upon failsafe activation ...

Many thanks in advance

Re: Failsafe with HKS EVC 6
 

What car is it?

Re: Failsafe with HKS EVC 6
 

Hi Richard ...

This is for a 997tt with gtx turboes .. Ext wg setup

Re: Failsafe with HKS EVC 6
 

Is this a 997.1 or 997.2?

Re: Failsafe with HKS EVC 6
 

Richard,

Its a 997.1tt ... Garret turboes and tial wg/bov

Re: Failsafe with HKS EVC 6
 

I made this drawing up, I think it should work.

http://www.aquamist.co.uk/HFS3/997TT/H3-997.1TT-HKS.gif

Re: Failsafe with HKS EVC 6
 

Nice illustration Richard, but I think you got the vacuum hoses hooked wrong ...

The boost referance hoses from the compressor should go into the middle "1" port, and gives feed to the lower port of the wg before going into the port. If I set the MAC before the Tee supplying boost referance to the wg it will cause un uncontrolled boost event ( WG will not see pressure and never open)

The control port on the evc 6 is the left "0" port, and it connects to both wastegates too ( Top or control port).

I will attach a diagram of the basic setup Im using ...

Re: Failsafe with HKS EVC 6
 

And another drawing showing a single turbo setup, its basically the same but with 2 of everything.

Basically to acheive my target "Failsafe" option, The top port on the external wg has to be vented to air, then the spring will be the sole boost regulator ... Just not sure how to acheive that with the mac valve,

Option A: on the boost referance hose (port 1 -middle) as you showed in the illistration, but definately after the tee going to the wg (Botttom), doing that will give the ebc no referance. ( not sure if it will work)

Option B: on the control vacuume hose (port 0- Left), this way I'm thinking to connect as follows:
Com - wg top port
NO - port 0 on stepper motor
NC - vent ( so when open its spring alone holding boost )

Let me know your thoughts about this Richard ...

Re: Failsafe with HKS EVC 6
 

The aquamist failsafe relay contact is "closed" when flow is normal. So the MAC valve is "energised" during a normal cruise and on boost conditions. Ie, port 1 &2 is connected. Diverting the boost into the HKS capsule, allowing it to control boost.

As soon as flow problem is detected, the relay contact goes "open circuit" and de-energises the MAC valve. Now the port 2 & 3 is connected. Directing the boost into the upper part of wastegate actuator resulting in dropping boost.

I will looking into this closely tomorrow. It is getting quite late here.

Re: Failsafe with HKS EVC 6
 

Yes Richard!! That will definitely work ....

Thank you for the quick replies and the nice diagram ...

Cheers