audifreakjim wrote:I have never had fuel starvation issues if above 1/4 tank on the track, although I never actually logged fuel pressure so who knows. The surge tank is really there just to submerge the Walbro pump, you can't just place them inline because they leak. See above a few posts.
The jets are .5mm green banded. I run a 6th right before the air temp sensor to trick the ecu into adding more timing. My pump is either 150 or 200 psi. Can't remember. It's high enough I don't worry about pressure drop on high boost.
All controlled by an aquamist fast acting valve on a spare injector channel that is enabled by a Hobbs pressure switch around 15psi
I also have an AEM fail safe system that monitors flow I plan on having it disable high boost if flow falls outside the normal map.
I have a lot invested in this system so it would have been silly not to run it! Only a few extra evenings so far to get it installed completely stealth mode.
In regards to the fuel, I run one of these gauges (in addition to 5 other gauges) in my S4. Its a nice unit and stores your max, so at any point you can hit a button to see your max from the last pull you did, or hold the button down and reset. Kind of a nice feature, so if you're at 30 PSI you can focus on the road.
http://www.demon-tweeks.co.uk/motorsport/gauges-auxiliary/spa-design-turbo-boost-fuel-pressure-dual-gauge
The AEM failsafe is a must! The only issue I have ever had with it is if the pump flow is somewhere in between low and high. I have seen a scenarios before when it was clogged where it was at about 200 ml/min and so it was enough to not trigger the failsafe but less flow than I want.
It's really a cool system when set up right!
