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42lb injectors

  • Thread starter Thread starter boosted mustang
  • Start date Start date Jan 16, 2010
B

boosted mustang

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Jan 3, 2010
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Jan 16, 2010
#1
  • Jan 16, 2010
  • #1
will a a9l run 42lb injectors with a proper maf without a tune
 
B

boosted mustang

New Member
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#2
  • Jan 16, 2010
  • #2
sorry should of mentioned on a 302
 
8

885.0conv

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Jan 16, 2010
#3
  • Jan 16, 2010
  • #3
As long as the MAF is calibrated to the 42# it should be ok. When you change the inlet tube (for C&L) going to the maf for the 42 it will make up the difference from going from the stock 19 to the 42 since extra fuel is going in on the 42#. What mods are on your car?
 
B

boosted mustang

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#4
  • Jan 16, 2010
  • #4
stock bottem, canfield heads, anderson cam, 1.7 roller rockers, gt 40 upper and lowerer. I put the 42s in the car with c/l mass air and my air fuel was every were on my aem a/f. would not steady out from 10 to 17 and swithched back to 19s and everything was good. Any idea what that is about
 
J

JustaMustangguy

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#5
  • Jan 16, 2010
  • #5
Well i can tell you one thing for sure. Given what you stated your combo to be. Why would you even consider changing injectors? Let alone 42's!!
Posted via Mobile Device
 
B

boosted mustang

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#6
  • Jan 16, 2010
  • #6
i have turbo kit sitting in my house awaiting a good running motor to put it on. so i kinda need bigger injectors. I doent want to put it on till i get problems fixed
 

SpartaPerformance

10 Year Member
Nov 5, 2006
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Long Island NY
Jan 16, 2010
#7
  • Jan 16, 2010
  • #7
I'm not surprised your a/f was all over the place, the sample tubes on C&L MAF's are good but you still need a proper tune, especially with 42lbs. Sample tubes are really for WOT operation
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,179
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Massachusetts
Jan 16, 2010
#8
  • Jan 16, 2010
  • #8
That sort of mod level, you should really be looking at a tune.

Calibrated MAF's is sort of a 'hack" method that developed because it was all there was in the 90's. Nowadays, tuning is the way to go...albeit more $$$
 
J

Joey7508

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Oct 23, 2005
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Kerrville TX
Jan 16, 2010
#9
  • Jan 16, 2010
  • #9
you can drive it around NA on them but once you are "supernaturallyasperated" you should or will need to tune it. I drove my 302 combo aounr on 42s till I got my turbo kit on.
 
B

boosted mustang

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Jan 17, 2010
#10
  • Jan 17, 2010
  • #10
see thats the thing at wot my a/f is good and steady at like 12.5 but at cruising speed or idle it is everywere. most of the time its peged at 17 or so but when its rich it will surge like a bitch!!!! I was maybe thinking it had to do with no tune on it. but by the way it sounds theres other people running on them on N/A motors. I just want to make sure everything works good before i put it all together and take it in for a tune. I doent want to bandaid anything and want everything to work good. The only thing I doent understand is arnt the O2 sensors suposed to control A/f at idle and cruising which would be considerd open loop right? and wot is in closed loop?
 
B

boosted mustang

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#11
  • Jan 17, 2010
  • #11
sorry i think i might of got closed loop and open loop backwards?
 
J

JustaMustangguy

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#12
  • Jan 17, 2010
  • #12
Those injectors are just WAY to much for your combo. Put the 19's back on. IF and when you put a power adder on, then use your 42's
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B

boosted mustang

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#13
  • Jan 17, 2010
  • #13
just out of curiostity what is proper air fuel for 19lb injectors? Im sure it depends on ur combo. I did put the 19 lbers back in and it cleaned things up but to me it seems to running alittle to lean it hangs around 14 or so when cuisin steady and idle is lean at 17. but it fixed my idle issues they r gone. The mass air is just a stock ford mass air from factory that i put in with the 19lbers.
 
B

boosted mustang

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#14
  • Jan 17, 2010
  • #14
just thinking do you think mayby i got my o2 sensor for the a/f to far back in the exhaust its like 14 to 16 inchs behind the stock o2 on the drivers side. would that giv it a false reading?
 

89blackbetty

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Jan 16, 2010
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#15
  • Jan 17, 2010
  • #15
Just my .02 cents...but idk why you would even play with 42lbs on what you have. Of course things arent going to run right. Im with JUSTAMUSTANGGUY and say leave the 19# in untill you get everything you want together for the turbo setup then put it on and have it tuned the proper way. Right now it doesnt know what to do.
 
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