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Need help with injector sizing and confusion on fuel leaning issues, Help

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Old 02-08-2002, 03:59 AM
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tecart
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Post Need help with injector sizing and confusion on fuel leaning issues, Help

Hey Guys i need bigger injectors i think for my 86 turbo and i heard of 42,52,55,72 pound ones as an upgrade but what are you guys using? i need them because im going lean on my air/fuel ratio meter while on 3/4 to full boost, my car is using a maf#4 kit with arm1, arc2, k29#8 turbo, adj. wastegate and boost, my arc 2 settings are Low 11:00 Mid 2:30 High 2:00 Accel 1:30 but im going full lean if i turn my High **** below 2:00. I even turned the adj. fuel pressure reg. to 58 psi of fuel pressure (from 46 psi) at idle with the vac. line disconnected but i didnt get any help on the leaning out part(if i set the high **** below 2:00 i will go to the far left red lights on the meter at full throttle meaning very lean!! so i wonder is this all because i need bigger injectors or is it because its normal to set the High **** to my 2:00 position and higher and just leave it there without getting bigger injectors? Im just confused to that and also if i go with bigger injectors meaning ill get a same fuel with lower fuel pressure and a lower high **** setting does that equal more power than what im doing now to my car? So in summary: #1 is my arc2 setting fine or should i go with bigger injectors? #2 if i go with bigger injectors will i get more horsepower from my setup? I'm not sure i would get more power because im already running almost 60 psi of fuel pressure #3 what size injectors do i want to get for my setup and what OHM should they be? i heard low ohm like 2.8 is best then the next guy says high OHM like 8 is good, then next guy says youll fry your DME, god is this confusing, i just wonder if i go this way what OHM should the injector be? #4 where to buy this injector set for the best price and what make, Bosch, Simmens? Not to mention each maker makes the same pound injector at different OHM's again more confusion in deciding here...
Please respond if you can help and have these bigger injectors on you car with a bigger turbo and let me know
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tecart
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posted 02-08-2002 02:57
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also im running the boost between 17 and 23 psi dialed in for 17 psi max most of the time on my wastegate and i want my setup set for this area of fueling not less then these numbers, i man run less boost but want the fuel for 17-23 psi
Old 02-08-2002, 06:59 PM
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hey ian im not going lean if i keep the high **** above 2:30 only if i go lower then that do i go lean, but my point was if i go with bigger injectors and then i can lower my fuel rail pressure and put the high **** at 8:30 will i make more power than just leaving my car alone the way it is now? this is what im trying to figure out, is more power gonna be made if i get no leaning out but my high **** is at a low 8:30 or at a high like it is now 2:30 level? which high setting produces more power? im not leaning out as my car sits now with new stock 2.5 liter injectors but since my high **** is so much higher then everyone else i wondered if i lower my high **** to say like 8:30 or even 9:00 (again to do this level i understand i will need bigger injectors to lower my high **** and not lean out) will my car be making alot more power? am i loosing like 30-40 horses due to the fact my high **** is so high? Derrick at huntley says the high **** isnt meant to be run so high and it looses its efficiency or something to that effert? also lastly i am gonna get the 52 pounders from bosch but what Ohm should i get with it? thanks and please take it easy on me
Old 02-09-2002, 04:12 PM
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anyone reading this? thanks for a reply
Old 02-09-2002, 05:44 PM
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Yes, you need larger injectors. Many people have gone to 52-55lb/hr injectors from <a href="http://www.injector.com" target="_blank">Marren Motorspors</a> and reported their high-end lean air-fuel ratio went away. You have to dial back the fuel-pressure and make some minor adjustments to the ARC2, but that's it. The low-impedance peak&hold injectors like Bosch or Siemens seem to work well. Avoid the high-impedance ones like Rochestor/MSD.



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