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Would 42# injectors be allright?

  • Thread starter Thread starter Rhombeus50
  • Start date Start date Jan 11, 2004
R

Rhombeus50

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Oct 20, 2003
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Jan 11, 2004
#1
  • Jan 11, 2004
  • #1
I know my current N/A combo will be just perfect for 36# injectors. What if I was to get 42# injectors instead? Could I just back off the fuel pressure & run the car at the same level as w/the 36's? I wanna know just in case for the future when I upgrade & maximize my engine combo.
 

90mustangGT

I felt sorry for girls because
Founding Member
Jan 15, 2002
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Dallas, GA
Jan 11, 2004
#2
  • Jan 11, 2004
  • #2
Do you have the other upgrades nessasary to support that size of injectors, such as larger lines and fuel rails? 42#'s aren't that much larger, and your computer should compensate with shorter duty cycles, but programming I would think would be nessasary.
 
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Rhombeus50

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#3
  • Jan 11, 2004
  • #3
Yeah, I'll for surely get a chip burned, but what's the limit on injector size for the stock fuel rails?
 
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Rhombeus50

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#4
  • Jan 12, 2004
  • #4
Opinion?
 
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Highbredcloud

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Mar 4, 2003
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Palos Hills, IL
Jan 12, 2004
#5
  • Jan 12, 2004
  • #5
Personally I think the 30# would have been perfect for you as well...with your set up you're probably making betwen 360-380RWHP...42's I think are too much.
 
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Rhombeus50

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#6
  • Jan 12, 2004
  • #6
Yeah, but if I'm getting a killer deal on some 42's(same price as 30's) would I still be able to have the car run the same as it would with the smaller injectors? I just don't wanna have to buy new injectors in the future if I don't have to.
 
H

Highbredcloud

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Mar 4, 2003
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Palos Hills, IL
Jan 12, 2004
#7
  • Jan 12, 2004
  • #7
What else do you want to do to the car? I mean if you superchare it you will most likely have to switch to bigger injecters unless you want to use the FMU...if you get N2O you might get away with the 42's...If you're getting a good deal get them and sell them on eBay for more...However, too big is not always good especially when it comes to injectors since than you will have to re-calibrate your MAF if you have a Pro-M or get a new one to match the injectors...Personally I would get the 30# and a 255lph fuel pump and that's plent for a N/A motor...unless you plan on some sort of a power adder in the future than consider the 42's but remember that other things besides injectors and MAF will have to be change when you use a power adder...ex. tranny, fuel lines, suspension etc...
 

86Cobra

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Jan 12, 2004
#8
  • Jan 12, 2004
  • #8
Rhombeus50 said:
I know my current N/A combo will be just perfect for 36# injectors. What if I was to get 42# injectors instead? Could I just back off the fuel pressure & run the car at the same level as w/the 36's? I wanna know just in case for the future when I upgrade & maximize my engine combo.
Click to expand...

36s would probably be perfect, but 42s will work with a good custom chip tune.

Fuel pressure isn't the answer. I run 36s in my 306 at stock fuel pressure w/o any issues but I use a Tweecer RT to tune it. With a chip or a tuner like a Tweecer, you tell the EEC directly what size injectors you have and your mass air tranfer function (air mass vs voltage).
 
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