I just installed the DSX Low Side system on my 2017 Z06. Pump definitely works and turns on as soon Fuel Mode hits "High Flow". Now the low pressure looks great, it's the high pressure that's the problem. I'm running E30, just like I was before the added pump and high side would stay pretty close to the desired pressure under full throttle. Now the high side pressure drops to 1,000 psi (even 800 sometimes). AFR (Lambda) is constant at around 0.82 at full throttle even though the high side pressure is really low. I've only done limited runs on the street in 2nd and then in 4th gear. As soon as it goes into "High Flow" mode, the requested low side pressure jumps to 73 psi and the aux pumps turns on. Low side pressure jumps to 86 psi or so, confirming pump operation. At the same time high side pressure begins to drop. After 1.5s in High Flow mode, the high side pressure is right at 1,000psi and low side has dropped to 76 psi. That's as far as I went before letting off the gas (4th gear (auto), 5,000 rpm, 96 mph). Lambda solid at 0.83. Injector Pulse Width is quite a bit higher than previously. It's up to 10-11 when the aux pump kicks on. Didn't change anything else, so this is a real mystery. Any help would be appreciated.
Has anyone seen similar results? High side pressure being that low is pretty scary, but at the same time AFR is still good.
For Completeness here are the mods on the car:
Headers, off-road X-Pipe (no cats), stock mufflers
15% over-size lower pulley
Ported Throttle Body
Cold Air Intake
DSX Flex Fuel Sensor
DSX Low Side Pump and Controller