Boost/Vac FPR double check please
Boost/Vac FPR double check please Setting up my aeromotive adjustable FPR. I have it boost/vac referenced from the manifold. Whats the procedure to set base pressure? I am thinking I will plug the vacuum port and set it to 58psi while running. Then reattach the vacuum line.
Also using hptuners. Sounds like I need to copy the 0kpa value from the injector flow rate vs kpa table and paste this across all cells. Can anyone confirm?
Thanks!
Also using hptuners. Sounds like I need to copy the 0kpa value from the injector flow rate vs kpa table and paste this across all cells. Can anyone confirm?
Thanks!
Anyone? Fuel pressure is set to 58 psi at idle without seeing vacuum. When I reconnect the vacuum line, the regulator is not dropping pressure. The FPR is supposed to adjust 1:1 - Aeromotive A1000. Will the a1000 only increase with boost pressure and not drop when it sees vacuum? Assuming that it is set to adjust 1:1 in psi, with -18 in Hg of vacuum (roughly -9 psi), shouldnt the regulator drop to roughly 49psi?
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From: Norn Iron
If you have applied intake vacuum to the regulator then fuel pressure will drop at idle ( assuming there is vacuum in the intake )
it may not drop the 9-10psi you expect, but it should be pretty close to 1:1
Vacuum source is via a vacuum block tied to the back of the intake. Maybe I will try hooking a mityvac up to the regulator while the engine is running. If I can pull a decent amount of vacuum with that, I should be able to rule out a faulty regulator. I can see the fuel pressure fluctuating 2-3 psi when raise the RPM's up to 2500-3000. Im just not seeing the pressure changes I expected. Thanks for the input.
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From: Norn Iron
Mityvac would be a good test. As would a simple rev.
Fuel pressure should rise as you stab the throttle and there is less vac in the intake, then it should fall again on the overrun when there is more vac in the intake, then stabilise again at idle.
But Mityvac would be best.
Fuel pressure should rise as you stab the throttle and there is less vac in the intake, then it should fall again on the overrun when there is more vac in the intake, then stabilise again at idle.
But Mityvac would be best.
Anyone? Fuel pressure is set to 58 psi at idle without seeing vacuum. When I reconnect the vacuum line, the regulator is not dropping pressure. The FPR is supposed to adjust 1:1 - Aeromotive A1000. Will the a1000 only increase with boost pressure and not drop when it sees vacuum? Assuming that it is set to adjust 1:1 in psi, with -18 in Hg of vacuum (roughly -9 psi), shouldnt the regulator drop to roughly 49psi?
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9 Second Club
Joined: Nov 2003
Posts: 13,616
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From: Norn Iron
Ok I see what you are saying....No I believe once you set the base pressure that is where is will be at 0psi or vacuum. Only way it can change is by going up with intake pressure of course. After seeing no more intake pressure it should reside back onto its base pressure. I am welcoming anyone to correct me if I am wrong though
Fuel pressure will track intake manifold pressure for as long as the signal line is attached.. That can either be up, or down.
Base pressure is referred to as such with no vac line connected so should always be constant assuming no other problems.
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Verdad Gallardo So a vacuum will pull the fuel pressure down past the base?
Yes, intake vacuum actually "sucks" more fuel out of the injectors, therefore the regulator will reduce pressure to compensate. Boost pushes against the injectors, making it harder for them to flow, therefore fuel pressure must be increased to overcome the resistance.
^^^ This guy is correct. I will update this when I get a chance to work on the regulator. Had a tick in the valvetrain yesterday. I decided to pull the rocker arms and pushrods to inspect them. Once I get everything back together I will work on the FPR again.