Took car to dyno today, have fuel issues
#21
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On another note, if I am already having issues like this, should I start looking into a dual feed fuel rail? I think there are some DIY methods posted here, I just don't want to mess with stuff unless I need to.
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Does anyone have a recommendation to hook up a fuel pressure gauge to a returnless (03) system? The hard lines run to the FPR which then has a quick-release. Do you just cut the soft line that goes to the rail and T in with the gauge? I'd think you'd need a new quick release line after that.
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when I put in my dual feed rail, I just pulled the quick disconnect fuel lines out (get the tool) and put hoses and clamps on the hard lines. they've got the equivalent of a bead roll on them already.
oh and get a dual feed rail so it's worth your while.
oh and get a dual feed rail so it's worth your while.
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thanks guys. Any suggestions for a good place to buy said fuel pump? I read through some of POPSTOY's threads on M.net and he seems to favor the 255lph Walbro pump. Though I am not sure if that will give me issues with idle tuning or not. Since I have the Hydra, I assume I can meter the fuel enough to adequately control the idle, but I want to make sure. So should I get the 190 or the 255?
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Lightining motorsports for the pump. Got my 190HP from them and they were good to deal with.
http://www.lightningmotorsports.com/index1.htm
http://www.lightningmotorsports.com/index1.htm
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Lightining motorsports for the pump. Got my 190HP from them and they were good to deal with.
http://www.lightningmotorsports.com/index1.htm
http://www.lightningmotorsports.com/index1.htm
http://shopping.lightningmotorsports..._Kit-p-89.html
Please confirm that I have the right one (they don't have one for 99+). Also, the 255 is only $10 more than the 190. I am leaning toward the 255 unless someone can come up with a good reason that I shouldn't.
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There are a few draw backs to a non-return fuel system, that need to be taken into account, the biggest of which is the inability of adjusting fuel pressure. It is fact, not opinion, that only the walbro 255 lph-hp is capable of maintaining 70 psi of fuel pressure above 5500 rpm with my engine producing 159.9 rwhp at 6850 rpm. It is also fact, not opinion, that with a walbro 190 lph-hp that my fuel pressure fell off to less than 50 psi at about 5500 rpm, and despite safe tuning was only capable of 145 rwhp, on the same dyno. Because you already have a return system, that allows use of a afpr, and the fact that the 99 head makes more power with the better atomization of higher fuel pressure, only being possible with the walbro 255 lph-hp, and an afpr, other than heat being transferred to the fuel, and excessive fuel flow being returned, I see no other detriment to using the big walbro, well maybe noise too. Oh, I used a fluidyne afpr, with a vacuum port, adjusting the fuel pressure to 60 at idle with full vacuum, at wot and no vacuum, it increases fuel pressure to 70 psi, a safe limit for injector reliability. Bob
#32
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I have the 255 HP in my car and the 99+ cars do need a pigtail adapter to make the Walbro work. The place below sells the pumps, but sold me the pigtail seperately. Hope this helps!
http://www.aztpi.com/product.php?pro...7&cat=0&page=1
http://www.aztpi.com/product.php?pro...7&cat=0&page=1
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BTW thought I'd mention that when I went to the dyno (York Automotive in Mt. Airy) I had a problem with going lean at high RPM irregardless of trying to add fuel in the Hydra map which is why I'm going to be replacing my pump and filter too.
#37
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Did you just solder/shrink them on? If that's all that's involved I won't worry about a pigtail.
BTW thought I'd mention that when I went to the dyno (York Automotive in Mt. Airy) I had a problem with going lean at high RPM irregardless of trying to add fuel in the Hydra map which is why I'm going to be replacing my pump and filter too.
BTW thought I'd mention that when I went to the dyno (York Automotive in Mt. Airy) I had a problem with going lean at high RPM irregardless of trying to add fuel in the Hydra map which is why I'm going to be replacing my pump and filter too.
Frank
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Well I ordered that pigtail from the link above. $8 plus shipping is acceptable for me not having my personal soldering and shrink tubing involved in my fuel tank... I am also going to order the 255 walbro today. Let's hope this fixes all of my fuel problems.
#40
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and plugging into this thread but I was always told or seen it on vendor pages not to run over 12 psi on stock internals on a NB, especially 2001 and up.
I would much prefer 14 psi -vs- 12 psi... so ..? don't really know what my question is.. but am I in the 'danger zone" if I up my boost to 14 psi? and tuned good?
Buck
I would much prefer 14 psi -vs- 12 psi... so ..? don't really know what my question is.. but am I in the 'danger zone" if I up my boost to 14 psi? and tuned good?
Buck