Remote Tuning

jax4557

I have the same setup as you but only S1.E, walbro 485, 1150cc injectors, E85. I also have fuel reference set to 42 psi, you should get 1 more psi of fuel per psi of boost. Can check by revving and watching your pressure under the hood if you don't have a gauge in the car. When I shut the car down my pressure stays around 40psi for a few minutes and then around 20 minutes later it will hit 30psi, I have not watched it long enough to see if it goes back to 0psi.

With the immidate 0 PSI on shutdown I would say you have an issue with your regulator, return line on regulator hooked up wrong, or maybe something in the fuel basket but I don't think that could be it..

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BP Precision 6766 - E85 - 620hp / 550tq

shadow85

Ok, thanks for the info.

Will try revving it on idle later tonight, see what it says.

turtle64b

Disconnect the vacuum line to the regulator and set the pressure to ~52psi with the vacuum line disconnected. Then reconnect the vacuum line and you should be good as far as fuel pressure goes. The car doesn't need as much fuel at idle and as stated earlier, and the linear changed in fuel pressure per change in manifold pressure allows the net fuel pressure to stay the same throughout the power band. I.e. 1psi of boost = 53psi fuel pressue => net fuel pressure is till 52psi

42psi is low. Also, you 100% have a fuel leak. Pressure should remain in the system long after you turn the car off. Like many hours.

turtle64b

The hybrid tune is a little easier (from what I've been told, I am not a tuner) to tune for driveability since you don't have to try to figure out parameters for the car to guess how much air it is getting. At low RPM, the ECU uses the MAFs to see exactly (theoretically) how much air the engine is taking in to adjust that way. Full SD is more time consuming due to the "guessing game" for air across the entire RPM range vice a specific one (i.e. high RPM/load of racing).

Driveability is a function of the tuner, in my opinion. A full SD tune can drive like stock with enough patience. A hybrid tune will get you that faster is all. If you look at your logs when you do WOT pulls, there is the Speed Density Digital (on/off) parameter that should switch "ON" at a predetermined threshold and then back "OFF" when you fall back below the trigger point.

shadow85

But I only just asked CJM this earlier today, and they said that aftermarket regulators are not designed to hold pressure after the pump is off. Some will hold pressure for a few moments and some will drop to 0 immediatly, and some might drop pressure halfway and take time to bleed the rest out.

jax4557

Exactly what he told me back when I needed info on my cjm setup, like I said mine will hold for a while but yours may not and if he says that's normal then that is ok.

Also, Seb had me set fuel pressure regulator to 52 psi with vacuum reference off, then when you connect it to the vacuum it will go to 42psi roughly. Every psi of boost will push back an extra pound of fuel pressure to combat the cylinder pressure to the injectors so you are always running 42psi. At least that is my setup.

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BP Precision 6766 - E85 - 620hp / 550tq

turtle64b

They are much more knowledgeable than I, no doubt, so if they say cool, then cool.

Your pressure drop-off coupled with the smell of fuel is what points me to a leak. When I started up the car for the first time after the install, the pressure gauge on the regulator was too loose. You could definitely smell the gas and pressure would drop off to zero in under a minute. After getting it all nice and tight and verifying the other joints, my pressure stays steady long after shutdown, which is why that just seems normal to me.

I went with the Fuelab regulator for my setup.

shadow85

I think I have the fuel lab aswell. I sure hope it is only a fuel leak somewhere that is also easy to fix and not some other problem causing lean condition under boost.