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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • Fox 5.0 Mustang Tech

HELP PLEASE

  • Thread starter Thread starter SC_LX_302
  • Start date Start date Feb 8, 2007
S

SC_LX_302

New Member
Jul 22, 2006
6
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0
Feb 8, 2007
#1
  • Feb 8, 2007
  • #1
HI I m all new to this. but I need help I have a stock 5.0 put a procharger on runing 10 lbs boost when the RPM gets up around 4000 and about 10 lbs I think it goes way lean poping and bad noise.FMU full rich and I am rubbbning a t-rex 50/70 do i need bigger injectors and if so what size THANK YOU
 
M

mike93lx

Member
May 22, 2003
391
0
16
Hudson, MA
Feb 8, 2007
#2
  • Feb 8, 2007
  • #2
Put together a sig with your mods, or at least list them. It'll make giving recommendations a lot easier.
 
S

SC_LX_302

New Member
Jul 22, 2006
6
0
0
Feb 8, 2007
#3
  • Feb 8, 2007
  • #3
T-REX 50/70
PROCHARGER 600B 3 CORE I/C
ALL OTHER STOCK
5.0 ho 1989
 

eagleautosports

New Member
Jul 7, 2006
139
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0
Mebane NC
Feb 8, 2007
#4
  • Feb 8, 2007
  • #4
Hope you've got at least 30 pound injectors, 42 would be best cause it sounds like the detonation demon's arrived. If you have stock 19 lb injectors, do not get into the boost or serious engine damage will happen and things will get ugly. This also means a new MAS sensor calibrated to the injector size and new engine tune along with the FMU. I really hope you're not running 19 pounders on there... please say you're not.
 
M

mike93lx

Member
May 22, 2003
391
0
16
Hudson, MA
Feb 10, 2007
#5
  • Feb 10, 2007
  • #5
i'll definitely second bigger injectors. get them upgraded ASAP and a new mass air meter.
 
S

SC_LX_302

New Member
Jul 22, 2006
6
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0
Feb 11, 2007
#6
  • Feb 11, 2007
  • #6
yes I hate to say 19 if that comes stock

THANK YOU I am finding out a kit is not the hole ball of wax
 

sixxer

New Member
Feb 9, 2007
13
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0
AL
Feb 11, 2007
#7
  • Feb 11, 2007
  • #7
Hey my bud is running a pro on a 93 cobra and had to basically just take the car to a dyno and let the guys there set it up. He ended up changing out chips and the fmu that came with the kit. Also, if you go bigger injectors, and mass, you might want to look at a really good fuel pump. I would also suggest turning the boost to around 7psi if you do alot of city driving, the stop and go is hell on the motor and the pro especially in the summer.
 

eagleautosports

New Member
Jul 7, 2006
139
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0
Mebane NC
Feb 11, 2007
#8
  • Feb 11, 2007
  • #8
Then I'd say 42 pound injectors are what you need, and that means you'll have to get a new MAS calibrated for them and then retune the FMU and computer for the new system. Do not run the engine hard anymore until you get this done or blown head gaskets, cracked block, piston damage or warped heads can result. If it's your only car, don't get into the boost if at all possible and I hope you get it worked out.
 
S

SC_LX_302

New Member
Jul 22, 2006
6
0
0
Feb 11, 2007
#9
  • Feb 11, 2007
  • #9
yes I hate to say 19 if that comes stock

THANK YOU I am finding out a kit is not the hole ball of wax
 
S

SC_LX_302

New Member
Jul 22, 2006
6
0
0
Feb 11, 2007
#10
  • Feb 11, 2007
  • #10
mass air flow

what type of mass air flow meter and what size injectors ?
 

sixxer

New Member
Feb 9, 2007
13
0
0
AL
Feb 11, 2007
#11
  • Feb 11, 2007
  • #11
SC_LX_302 said:
what type of mass air flow meter and what size injectors ?
Click to expand...

The best way to set it up is to call ATI and ask them what they recommend for their system. They might have some of this info on their site, been a while since I've been there.
 

eagleautosports

New Member
Jul 7, 2006
139
0
0
Mebane NC
Feb 11, 2007
#12
  • Feb 11, 2007
  • #12
42 pounders and an 80mm C&L MAS. Make sure it's calibrated to the injectors and then tune the FMU. Another thing, get some copper spark plugs 2 heat ranged colder than stock, they'll fight the detonation better.
 
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