So after some discussion in a recent turbo thread, I'm thinking it might benefit me to add an external fuel pressure regulator since the car is turbo'ed.
Secondly, how would this be installed? Inline with the stock fuel rail/FPR? Would you have to gut the stock FPR so it didn't interfere with the operation of the external one?
Also, if I do this, I'm thinking of dropping down to 19lb injectors. Would this combination be easier to tune than the current 24lb injectors with the stock FPR?
My preference for reliability and ease of service is the Mallory bypass filter. I've had one for the past 7 years and it is absolutely reliable and fully adjustable.
The description seems to suggest it has 2 ports plus a return line. If that's the case, then you would plug the return port on your fuel rail, because it wouldn't be used. You would also have to delete the stock fuel pressure regulator.
As for which injectors to use, depends on your engine's power output. If it's under 200HP (at the flywheel), then 19 lb injectors should suffice. Otherwise, I'd stick with the 24 lb injectors.
Just out of curiosity, why are you wanting to add an external pressure regulator? Are you planning to use it to tune the fueling? If so, that's not the best approach. You may end up running pig-rich at idle when you tune for WOT, or super-lean at WOT when you tune for good idle. The best approach would be to reprogram the ECM.
Also, I found out the hard way that the stock pressure regulator doesn't handle 60+ PSI very well. So if you plan to run high fuel pressure, the external regulator might be a good idea anyway.
You should delete the stock regulator, and it would be in the return line. Rising rate would be helpful because then the fuel pressure relative to the intake pressure stays constant. Same way that the stock regulator lowers fuel pressure under vacuum.
I think the description is a little misleading. You can run your lines multiple ways with regulators like that (at least with the Aeromotive one I have). You can run the regulator inline before the rail and have a returnless setup, or you can run it after the rail inline on the return side like stock. Either way the bottom port is going to be the return to the tank and the difference is the where the pressure is regulated, either before or after the regulator. For a stock setup you would run from the rail to a side port (plug the opposite side) on the regulator, and then from the bottom port to the tank return. For a returnless style you would run from the tank/filter to a side port on the regulator and then from the opposite side to the rail. The bottom port returns to the tank again.
If your stock regulator along with tuning is sufficient for your system consider my advice and leave it alone, otherwise you'll need to research the part you intend to buy and incorporate into your system very well. Some of the aftermarket regulators work best in race applications because some have a little difficulty holding a steady fuel pressure under low loads where it matters most when you're trying to maintain a closedloop idle. I took the Mallory bypass regulator I had off because running it near the base fuel pressure of 40 psi was a little unsteady at times per my electric fuel pressure gauge. I also read complaints about this sort of problem on the net when used in daily driven cars controlled by the ECM.
The description seems to suggest it has 2 ports plus a return line. If that's the case, then you would plug the return port on your fuel rail, because it wouldn't be used. You would also have to delete the stock fuel pressure regulator.
As for which injectors to use, depends on your engine's power output. If it's under 200HP (at the flywheel), then 19 lb injectors should suffice. Otherwise, I'd stick with the 24 lb injectors.
Just out of curiosity, why are you wanting to add an external pressure regulator? Are you planning to use it to tune the fueling? If so, that's not the best approach. You may end up running pig-rich at idle when you tune for WOT, or super-lean at WOT when you tune for good idle. The best approach would be to reprogram the ECM.
Also, I found out the hard way that the stock pressure regulator doesn't handle 60+ PSI very well. So if you plan to run high fuel pressure, the external regulator might be a good idea anyway.
My main reason for wanting to run an external is that some varying opinions came up in another thread regarding how the stock regulator works when boost is applied to it since it is designed to work off vacuum...although to be honest I don't know how external FPR's are designed compared to the stock one. I guess I'll stick with 24# injectors as my HP goals are 200 or over.
quote
Originally posted by mikejhjr:
How is your fuel system setup now, is it stock?
Stock setup just with an adjustable FPR like the Holley unit the FieroStore sells.
[This message has been edited by ConvictedRedneck (edited 07-08-2013).]
You can make plenty of horsepower with that setup. I really suggest trying out something other than $8F. As I said in the other thread, code59 is working for me. You don't need a wide band O2 with this code but it sure helps. Or keep tweaking $8F. It works, just takes a bunch of fine tuning.
Yeah I saw your post and I'm definitely thinking about trying code59. I have a Innovate MT-X wideband but I don't know if it has the ability to be run to the ECM...I believe it does though. Thanks for the tip and I might be PM'ing you as soon as I get my Ostrich. How similar are our setups? I don't recall offhand what you had.