Fuel Injector Info
10-28-2009, 10:29 AM
#77
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anybody have the color coded diagram up.. Can you please post the one MM posted is not showing. I believe I have found my everlasting problem here. It looks as if when I installed my injectors I wired the 2 middle P2 injectors wrong. To my front p1 injector I have green/white & blue/white wire connected to it and my rear p2 injector the black/blue & blue/white wire are connected to it. This is incorrect isn't it?
10-29-2009, 09:18 AM
#80
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if I want to change some injectors... do I have to change all the 6? or try strating by the red ones and pluging the red one instead of the yellow ones...etc...
10-29-2009, 08:40 PM
#82
Hmmmmmm.........
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The factory ECU has the Injectors grouped. You set the CC/min and dead times for the primaries as one group and for the secondary and aux injectors as another. So as long as you change the primaries as a pair and the secondary and aux as a group you are fine.
10-30-2009, 09:20 AM
#83
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10-31-2009, 10:28 AM
#84
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I take that is the Pettit stage II?
I have two 780cc/min low-impedance injectors if you want them. I ran them for a month with absolutely no issues but decided to go with 4 650cc/min across the second fuel rail instead of two 650s and two 780s.
I will say that the stock pcm is made to run high-impedance injectors. You would have to risk running the low-impedance injectors like I did or find something to drive them. The risk is that you might over heat the pcm. I think that risk is slight if you only run 2 out of the 6 as low, but that is only based on my experience with having no issues. If you are using a microtech unit (an int-x) to control your fuel, you will have no problem as it contains low-impedance drivers.
I have two 780cc/min low-impedance injectors if you want them. I ran them for a month with absolutely no issues but decided to go with 4 650cc/min across the second fuel rail instead of two 650s and two 780s.
I will say that the stock pcm is made to run high-impedance injectors. You would have to risk running the low-impedance injectors like I did or find something to drive them. The risk is that you might over heat the pcm. I think that risk is slight if you only run 2 out of the 6 as low, but that is only based on my experience with having no issues. If you are using a microtech unit (an int-x) to control your fuel, you will have no problem as it contains low-impedance drivers.
11-01-2009, 08:35 AM
#86
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Yeah. I agree. Plenty of examples of honduhs and others toasting computers; however, not a single example on an RX8 (that I am aware). I am wondering if I wasnt lucky, but that the total resistance was enough to protect the pcm.
Then again, the fact that I made it close to a month with the low impedance injectors may be only a reflection that these injectors were rarely used (in sec position iirc.)
Then again again, the second that I understood that I was running low-impedance injectors on a stock pcm I parked the car. I even pushed it into the garage.
I will admit that I want to get rid of these injectors.
I also have four yellows I dont need!
Then again, the fact that I made it close to a month with the low impedance injectors may be only a reflection that these injectors were rarely used (in sec position iirc.)
Then again again, the second that I understood that I was running low-impedance injectors on a stock pcm I parked the car. I even pushed it into the garage.
I will admit that I want to get rid of these injectors.
I also have four yellows I dont need!
Last edited by carbonRX8; 11-01-2009 at 08:43 AM.
11-01-2009, 08:58 AM
#87
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thanks carbone :D but i'll buy some new ones...
I read on an other thread that if I take large injectors, I have to reflash the PCM.
no big deal!
but will the OEM fuel rail accept that difference ? as the fuel pressure regulator ?
SO if I understannd right, the first injectors that can be changed are the P2...
I'll look for SARD injectors!
I read on an other thread that if I take large injectors, I have to reflash the PCM.
no big deal!
but will the OEM fuel rail accept that difference ? as the fuel pressure regulator ?
SO if I understannd right, the first injectors that can be changed are the P2...
I'll look for SARD injectors!
11-23-2009, 09:16 PM
#94
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hey guys...i having a lil prob wit my 8. today me n my boys went to play some football, we got to the park without any prob. i started it no prob here also, but after driving for a while i notice it was starting to lose power as i step on da gas n cuts off. could this be to a bad fuel injector?
11-23-2009, 09:33 PM
#95
/\ probably not
Moving on , I'm thinking of trying the following injector combo , any thoughts ?
P1 380 Secondary 480 P2 380
reasoning : increasing P1s will suffice for low rpm boost and having more fuel to the secondaries will even out the amount of fuel per intake tract to some extent .
Moving on , I'm thinking of trying the following injector combo , any thoughts ?
P1 380 Secondary 480 P2 380
reasoning : increasing P1s will suffice for low rpm boost and having more fuel to the secondaries will even out the amount of fuel per intake tract to some extent .
11-24-2009, 07:56 AM
#96
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hey guys...i having a lil prob wit my 8. today me n my boys went to play some football, we got to the park without any prob. i started it no prob here also, but after driving for a while i notice it was starting to lose power as i step on da gas n cuts off. could this be to a bad fuel injector?
no more fuel
01-13-2010, 01:26 AM
#97
I can't help but wonder how many people erroneously changed their injectors because they relied on some unverified published numbers rather than taking a set of unmodified OE injectors and actually having them cleaned & flow tested for an accurate baseline reference point?
01-13-2010, 01:33 AM
#98
I can't help but wonder how many people erroneously changed their injectors because they relied on some unverified published numbers rather than taking a set of unmodified OE injectors and actually having them cleaned & flow tested for an accurate baseline reference point?
I doubt anyone thought "Gee, my stockers are 293cc and I really want 314cc in that position, so lets swap them!".
Most people are going for double the OE flow or more.
01-13-2010, 01:47 AM
#100
The OE fuel system will probably suffice for most applications, though it might be on the edge.
Once you cross 300 HP, its worth the relatively minor expense to upgrade the injectors, especially in light of how thirsty the rotary is.
Cheap insurance.
And even if the published data is off by 20%, a 100% increase in capacity - even if its really 80% - is still a significant margin.
The actual flow values are a bit irrelevant as long as you know how to adjust the scaling in response to the difference between expected flow and actual AFRs.