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Old 11-05-2007, 05:55 PM   #21
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or put the stock afm back on. no reason you cant run 305s with it.

cause and point, back to back dyno runs with 305cc injectors and the RX7 AFM and OEM AFM.

oem won.


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Old 11-05-2007, 06:02 PM   #22
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i know there souldnt be a reason that i cant run 310s on the stock afm, but it does run like crap and rich as hell too
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Old 11-05-2007, 06:23 PM   #23
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everytime i touch the car, it gets worse. just put the stock afm back in with the 305s, its basically not drivable. studdering, super rich, boging and so on. there is no reason the car sould be running the way it is. i am going to go over the wiring harness to see if there is any damage.
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Old 11-05-2007, 07:03 PM   #24
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you = teh fail.

you got a wideband, what are the AFRs at idle?

drill out the cap on the OEM AFM to access the idle-mixture screw. back it out about a full turn counter-clockwise, should get you pretty close.
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Old 11-05-2007, 07:15 PM   #25
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back to basics here. did you check all the wires and plugs? I had a problem like this about 2 years ago, and solved it when I found the wires were breaking apart internally. I replaced the wires and plugs and that bog went away. That could be half your problem. Im willing to bet you have multiple problems here which are making your issues harder to figure out.

toss the origninal AFM in, new plugs and wires, and see what happens. that way you will avoid dealing with a potentially messed up AFM on top of the other problems. How about your fuel pressure reg? Did you check that?
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Old 11-05-2007, 07:24 PM   #26
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what am i missing here?:
too much fuel being delivered
poor ignition

Check:
Fuel pressure reg for proper pressure and functionality
your injector setup with respect to duration

What I would do:
put the original AFM on (to limit variables)
Put the original injectors in (to limit variables)
Check the fuel pressure
Check the injector durration

This should yield some answer, most likely a problem with your tunning. Tune the sucker, then one by one add your parts back on. Pretty time consuming, but i think that approach would solve it.

Braineak, what do you think?
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Old 11-05-2007, 07:37 PM   #27
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fuel pressure is exactly where it sould be, have tried the stock afm again. and 2 sets of stock injectors. plugs and wires are brand new NGK peices. i will clean off the plugs to see if it helps any. i have been messing with the screw on the afm for idle. several turns of the screw would only adjust it from 10:1 to about 11.3:1.
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Old 11-05-2007, 07:53 PM   #28
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Do I understand correctly here- your idle is sucking and when you put your foot into it, the car bogs? Its unlikely you have defective plugs or wires. but testing them and double checking the gap may be worth it. Also- your coil pack may be going bad, leading to issues with your ignition. Your AFM may be a dud for what your doing. hmmm... after checking your coilpack and wire/plug assembly, your next course of action as i see it is to try a different AFM to see if a different unit may get you the mixture your looking for. OH- I have not heard of it, but considering the fuel pump for a spike may be an issue. usually when a car 'bogs', meaning when you step into it, you have an over rich mixture. normally that means your not igniting the air fuel mixture, or their is too much fuel. make the distinction between those two possibilities. it sounds like you are supplying the mixture with a sufficient spark, but youll have to check the gap and ignition coils now to know for sure. after that im betting on the likelyhood that there is just too much fuel- this leads us to the fuel pump, fuel pressure reg, and injectors. I have absolutely no experiance with compression problems, but if you do not have sufficient compression, then there is the possibility that your car would bog also.

check:
ignition coils/pack
spark plug gap
compression

then:
fuel system and associated components
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Old 11-05-2007, 07:54 PM   #29
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what ratio are you looking for from the AFM?
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Old 11-05-2007, 08:01 PM   #30
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i have tried other injectors and AFMs, none helped. car ran fine pre-turbo. when i turboed it, i put in new plugs and wires. the car already has a 255 fuel pump in it. its running rich, spark isnt the problem. its just sucks through gas. its not a mechanical problem, its and electrical/sensor problem somewhere
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Old 11-05-2007, 08:10 PM   #31
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Doesn't the 255 over power the stock fuel pressure regulator thus making it uncontrollably rich. Thus the reason why people go for the 190 lph. Maybe that was only under power though, i'm not the one that would know off hand.
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Old 11-05-2007, 08:18 PM   #32
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no, the 255 does in fact overwhelm the oem fpr. so it's always rich. like 45psi at idle vs. 35psi.
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Old 11-05-2007, 08:24 PM   #33
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acording to my fuel pressure guage, idle is 36psi and 0vac is 45psi. i have had the 255 in for a long time, never had a rich problem when i was N/A
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Old 11-05-2007, 08:27 PM   #34
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beats me then.
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Old 11-05-2007, 09:21 PM   #35
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I'd check the voltage on your narrowband o2 sensor feeding the ecu (unless you are using NB sim from your WB to feed your ecu that is). It could be a dying/dead NB sensor.
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Old 11-05-2007, 09:42 PM   #36
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i replaced it also with a new one, no difference
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Old 11-05-2007, 10:30 PM   #37
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o2 sensor?
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Old 11-05-2007, 10:31 PM   #38
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Do a pressure leak down test with your piping and intercooler. Random chance you caould have a boost leak cauz your getting fuel but no air to mix with.
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Old 11-05-2007, 10:38 PM   #39
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boost guage holds nice and steady at 9psi, and idle vac is nice and steddy
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Old 11-05-2007, 11:21 PM   #40
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For got to ask but are you running a piggyback or just the FMU?
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