High-volume fuel pump = increased fuel pressure?
10-28-2011, 11:14 PM
#22
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It may be an XB-thing only. When the car was new it was so bad that it stalled sometimes. Later when I installed my UEGO I saw what was happening. 10:1 idle AFR after filling up, goes to 14.7 when I pull out and remains there afterward. Weird...
Thanks Crush! I may take you up on that but first I need to see if I can even install a new pump and still keep the oem FPR.
Thanks Carlanga, that's great to hear. I'm stubbornly pursuing my no-piggy setup to see if I can take it just a little further. I'm pretty sure the only thing holding me at 6 psi is reduced fuel pressure during high-rpm boost. A bigger pump may be enough for 7psi.
Hey man! I remember you well. How's life treating you these days? Still got the boosted TC?
BTW, I have spent a lot of years on computer hardware forums. My previous hobby was building and overclocking PCs. AFAIC cars are more fun but IDK, YMMV.
hey Fred right after I first installed the turbo, I went ahead and did a pump swap from stock to 255 walboro. Only thing I saw was a 6-8% drop in duty cycles and a tap bit richer in certain areas of the map. My guess because the extra flow and mainly the fuel delivery curve is different than the stock one. You should have no problems, just a tad richer than normal. Difference is I was able to change it with the fic.
Thanks Carlanga, that's great to hear. I'm stubbornly pursuing my no-piggy setup to see if I can take it just a little further. I'm pretty sure the only thing holding me at 6 psi is reduced fuel pressure during high-rpm boost. A bigger pump may be enough for 7psi.
fred I swear brother I always get caught up trying to read your post you have spent many years with computing and forum lifestyles that you use such big abbriviation hell it took me months to realise what you meant by AFAIK.
Btw not going to mention my name here but I'm that guy you sold an aem fic to about 2 years ago and I also came by again to pick up your old cx turbo
Btw not going to mention my name here but I'm that guy you sold an aem fic to about 2 years ago and I also came by again to pick up your old cx turbo
BTW, I have spent a lot of years on computer hardware forums. My previous hobby was building and overclocking PCs. AFAIC cars are more fun but IDK, YMMV.
10-28-2011, 11:36 PM
#23
It may be an XB-thing only. When the car was new it was so bad that it stalled sometimes. Later when I installed my UEGO I saw what was happening. 10:1 idle AFR after filling up, goes to 14.7 when I pull out and remains there afterward. Weird...
Thanks Crush! I may take you up on that but first I need to see if I can even install a new pump and still keep the oem FPR.
Thanks Carlanga, that's great to hear. I'm stubbornly pursuing my no-piggy setup to see if I can take it just a little further. I'm pretty sure the only thing holding me at 6 psi is reduced fuel pressure during high-rpm boost. A bigger pump may be enough for 7psi.
Hey man! I remember you well. How's life treating you these days? Still got the boosted TC?
BTW, I have spent a lot of years on computer hardware forums. My previous hobby was building and overclocking PCs. AFAIC cars are more fun but IDK, YMMV.
Thanks Crush! I may take you up on that but first I need to see if I can even install a new pump and still keep the oem FPR.
Thanks Carlanga, that's great to hear. I'm stubbornly pursuing my no-piggy setup to see if I can take it just a little further. I'm pretty sure the only thing holding me at 6 psi is reduced fuel pressure during high-rpm boost. A bigger pump may be enough for 7psi.
Hey man! I remember you well. How's life treating you these days? Still got the boosted TC?
BTW, I have spent a lot of years on computer hardware forums. My previous hobby was building and overclocking PCs. AFAIC cars are more fun but IDK, YMMV.
10-29-2011, 01:52 AM
#24
Are you trying to stick with stock ECU because your trying to keep costs down, or because you like the fact that it runs smoothly? If its option 2, consider a return setup with a boost ref FPR - that way you keep stock fuel pressure while in vacuum, but under boost fuel pressure will increase linear to boost.
10-29-2011, 09:41 PM
#25
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Hey I'm doing well the car is boosted again on its second motor I am running a 60-1 turbo and I ran a 13.1 at 110 with a slipping clutch I recently joined the army a year ago and I'm stationed in korea right now and yes me and you have discussed your past hobby before that's why I brought up the years of computing
Glad to hear that you're doing well and congrats on a very good 1/4 ET. You can see my not-so-impressive ET in my sig. At my age remembering you is good, remembering everything we talked about, not very likely...
Are you trying to stick with stock ECU because your trying to keep costs down, or because you like the fact that it runs smoothly? If its option 2, consider a return setup with a boost ref FPR - that way you keep stock fuel pressure while in vacuum, but under boost fuel pressure will increase linear to boost.
11-03-2011, 04:11 AM
#27
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Seems like sound theory to me. the only way it wouldn't show up in the trims is if FP remains the same in closed loop but differs during peak fuel flow in open loop when the stock pump pressure dips and the bigger pump doesn't. Either way I've decided not to pursue it. Too much time and money for ~20whp just so I can shave a couple tenths.
11-03-2011, 04:28 AM
#28
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Seems like sound theory to me. the only way it wouldn't show up in the trims is if FP remains the same in closed loop but differs during peak fuel flow in open loop when the stock pump pressure dips and the bigger pump doesn't. Either way I've decided not to pursue it. Too much time and money for ~20whp just so I can shave a couple tenths.
11-03-2011, 04:32 AM
#29
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also, you could get a water/meth kit. although you wouldnt have a very controlled way to tune it (if your still on stock ecu) but your intake temps drop incredibly low and you'd have a safer/richer mixture, creating more power at the same time
11-03-2011, 05:29 AM
#30
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Those are good ideas but if I'm honest with myself the smartest thing I can do is leave everything as-is. I've met or exceeded all of my original goals for this project and even my weak A/T is holding up great. If I keep pushing I'll eventually find a limit and possibly a very expensive one.
Besides, I recently sold a WMI kit that I bought 2 years ago but never bothered to install. If I stay at 6 psi, I don't need to change anything and it's still cool to have a A/T Scion XB that can embarrass my buddies 08 R32
Besides, I recently sold a WMI kit that I bought 2 years ago but never bothered to install. If I stay at 6 psi, I don't need to change anything and it's still cool to have a A/T Scion XB that can embarrass my buddies 08 R32
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