Hi Guys Quick question planning to finally get my car tuned in the next month or so I have a spare rail which I was going to have AN ends welded on to run twin feed and return - though simply do not have the time to get this sorted out. Can I just get it tuned now as is with the 750cc injectors in the OEM setup and then at a later date do the twin setup with out the need to retune etc? Running GT2860R with usually supporting mods on a forged motor thinking should safely do 320-350rwkw @20psi though will probaly never see more that 15-16psi on the road. Thanks Guys Matt.
Sure, worst that I can imagine is you gain a little fuel pressure going to twins, although I seriously doubt any measurable variation
Thanks Rob - thought it would be the case. Will be using a Tomei FPR with a gauge on it so will pick up any difference. Would be more concerned going from tuned with twin feed/return to OEM, but no one in there right mind would do that.
May I ask what benefit is achieved by having twin fuel lines supplying the fuel rail? Are you running 2 fuel pumps? Or is it 1 fuel pump into a single line branching into 2 lines to the rail? Are you running 2 fuel filters as well? The fuel pressure regulator will determine the system pressure, regardless of the number of inlet lines.
I don't understand. Assuming you're converting to twin feed for a reason (it will change your fuel pressure) then you must understand that this will throw out the tune. Why would you have a tune done then immediately change the hardware?
The idea is more stability of pressure across all injectors as the fuel flows through fewer injector seats between dampener and reg hopefully reducing pressure drop across the banks. There are quite a few threads about it on here, obviously they're all arguments about the validity of different theories. But to the OP, fuel pressure is set after the rail so number of lines feeding won't affect it (and if your tune does go wonky then we'll have some evidence that twin feed does something). If anything you'll be running a little richer which shouldn't be too dangerous
Hi Graham more of a safeguard from 6 ever being starved of fuel. 1 pump>filter>Y block>rails>twin return to fuel reg. Won't affect pressure and it won't be immediate maybe something to do a year or two down the track. Want to get it sorted out now in particular for zedfest.
Hey Matt, Not sure if you recall but that is my fuel lines, AN fittings on stock rails, 750cc injectors. Turbo smart FPR single large intank pump. With the 2860RS depending on your heads I think you'll find closer to 350rwkw@20-21psi However I don't think that you'll notice a difference it you leave it in the stock set up for now. Choice is yours if you don't have time leave it for now and get the tune done! Be good to have it done for zedfest Procky.
Yeh that's what I'm planning to eventually do when I get the time to. You're right on the power level I will get it tuned to around the 23psi mark just to be safe if it ever spikes but I'm definitely not going to try chase every bit of power. Have a set of Tomei exhaust gears to put on to help it spool up and power to come on earlier at a small sacrafice up top maybe 10-15kw at most. Along with the n/a rear end should be fun.
Hey Andrew Looking at the same fuel pump that you have yourself - what's your verdict on it, is it noisy from inside the car? Also is it a direct fit into the tank? Also any extra wiring or just by-pass FPCU and let it run at full 13.5v - whatever the alternator is putting out... Coz has them at $150 with the sock and wiring for anyone interested. http://conceptzperformance.com/Cart...6&Car_Type=300&UID=20140204145115202.4.165.40 Matt
Very quiet pump, unsure on if it's a direct fit with the wiring, but I'd recommend running it straight off the battery, bypassing the FPCU.
In direct fit i meant as in physical size how it sits in the tank - haven't removed my original pump as yet. Wiring is no problem if I have to do some soldering etc easy done. My biggest concern in running the pump at full speed is heating the fuel. At 400L/h, a one hour drive on a 50L tank is going to be cycled 8 times and 30L will be cycled nearly 14 times. Double that for every hour thereafter. Heat from the engine bay in particular the rails is going to be directly transferred to the fuel. Does anyone know if the FPCU can still be used with the Walbro (n/a 2speed 7/13v FPCU) Matt
Matt its quiet as stock except when initially starting the car / priming Direct fit into the stock cradle . wiring I believe was similar I'm not 100% certain on FPCU but Give UAS a call 96209000 Ask john what they did to mine. Can't remember of top of my head and not near car to look
Hoping Rob - BlalckBeast will chime in, I think he had problems with heat in his pump running full speed especially on low levels, not sure if it was resolved though.
$150 is a good price for an E85 compatible pump! Isn't there a danger with running it direct to the battery as stated? (i.e. in the event of a crash it would continue pumping and have no safety cutout)
