Jenvey throttle bodies on an Alfa V6 24V photos.

[tipo158]

Here is a diagram of the Jenvey pressure regulator, as you can see, there is a vacuum port. Sorry, I meant pressure regulator, not gauge.

[LM mic]

To my knowledge this port is never connected to anything when using a separate jenvey throttle bosy and watever specific ECU ( Emerals or any )

[STR_Strat]

I think its up to you whether you use it or not. The fuel map will be written to take account either way, just make sure that you don't alter it after its been mapped. If you don't connect it to vacuum then it should be left open to atmosphere and not blocked off.

Dave

[Sando]

With an aftermarket ECU the mapping will (should) give you the correct mixture at all times so can't see why you would connect the vacuum. That's for sudden throttle openings with a standard ECU to richen the mixture.

You need a constant pressure at the regulator for the Aftermarket ECU to work with.

.....could that be the cause of you bad fuel consumption Dave?????

[Jeff]

You need a constant pressure at the regulator for the Aftermarket ECU to work with.

.....could that be the cause of you bad fuel consumption Dave?????

I did discuss this with the chaps at Emerald (basing fuel pressure either on atmospheric or manifold pressure). I was told that the ECU could work either way (ie mapped for one or the other) but that using manifild pressure as a reference was better.

I have fuel pressure set relative to the manifold, but i wonder if this doesn't add another factor making things unnecessarily more complex.

[tipo158]

I am using a stand-alone ECU, I'll have to pull out the manual and see what it states.

[LM mic]

Many of ECU racing type we used previously where connected only to an electronic sender fit on the plennum when using turbo engines only

[STR_Strat]

.....could that be the cause of you bad fuel consumption Dave?????

No Rob, mine is not connected.
I think the reason not to block it off is to make sure the pressure remains constant, blocking it off would create a sealed vessel so the pressure would vary dependant on temperature.

Dave