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331 fuel timing problems

  • Thread starter Thread starter dloop
  • Start date Start date Feb 15, 2009
D

dloop

New Member
Feb 15, 2009
2
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0
Feb 15, 2009
#1
  • Feb 15, 2009
  • #1
I have a D.S.S 331 with a holley systemax 2 kit with 30 pound injectors 70mm mass air meter and accufab throttlebody, 255fuelpump and fuel pressure regulator. My problem is that the car ideals very rough, smells like fuel and dies every now and then. So I'm not sure if i have the right fuel pressure or timing, among other things. A little guidence would be much appreciated.
 

Rick 91GT

Mustang Master
Nov 29, 1999
9,692
95
99
PA
Feb 16, 2009
#2
  • Feb 16, 2009
  • #2
70mm MAF, is that a Cobra meter?? Or is it really 75mm? That could be one issue...

I would start at 36-38psi of fuel pressure, vac off, and 15 degrees timing.
 
M

mike0227

Member
Dec 19, 2004
53
0
7
Houston Texas
Feb 16, 2009
#3
  • Feb 16, 2009
  • #3
Please clarify cobra meter? I have a Pro M 77 MAF for 30lb and fount the standard Pro M 30lb MAF curve does not work well at all so I use the PRO M Cobra MAF curve and it works fine. The main difference was in the idle and low RPM area. My PRO M does not have flow sheet (either my son or me lost it) though it does say 30 C.

Thanks for your help
 

Rick 91GT

Mustang Master
Nov 29, 1999
9,692
95
99
PA
Feb 16, 2009
#4
  • Feb 16, 2009
  • #4
mike0227 said:
Please clarify cobra meter? I have a Pro M 77 MAF for 30lb and fount the standard Pro M 30lb MAF curve does not work well at all so I use the PRO M Cobra MAF curve and it works fine. The main difference was in the idle and low RPM area. My PRO M does not have flow sheet (either my son or me lost it) though it does say 30 C.

Thanks for your help
Click to expand...

Mike, he calls out a 70mm MAF above, the 93 Cobra came with a 70mm I wanted to make sure it was a type-o and he wasn't using it. Most aftermarket meters are 75mm, old 77, old 80 or 95mm, or larger.

As long as you have a meter that is calibrated for your inj you should be fine. How are you running a different curve, the Pro-M is not reprogramable unless you send it back?
 
D

dloop

New Member
Feb 15, 2009
2
0
0
Feb 16, 2009
#5
  • Feb 16, 2009
  • #5
331 fuel air problem

thanks for the responces, and to clarify on the mass air meter, it is a C&L performance 76mm with a purple sampling tube. I'm just not sure if thats the right tube for 30lb injectors.
 

Rick 91GT

Mustang Master
Nov 29, 1999
9,692
95
99
PA
Feb 17, 2009
#6
  • Feb 17, 2009
  • #6
Purple is correct, you may also want to try rotating the meter I found my C&L 76mm to run a little better when tilted towards the fender.
 
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