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Injector chart? At what point are 19s too small, or 24s too big?

  • Thread starter Thread starter Fett
  • Start date Start date Sep 14, 2006

Fett

New Member
Nov 2, 2004
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Sep 14, 2006
#1
  • Sep 14, 2006
  • #1
I tried searching, but all I found were specific engine builds.

My setup is in my sig, while trying to figure out my bucking issue we determined that I am running lean. I am running 24lb injectors/MAFS, at 40psi with the vac line off. We upped the psi to 52, and it still wont puff black smoke, and the bucking seemed to quiet down some.

So I am thinking of going back to my 19lb injectors and MAFS, in the theory that my 24s are bad. They were used and had 80k miles on them.

So in short, at what point do you need to up to 24s, or at what point would you benefit from 24s?
 

JChalfan

Member
Nov 27, 2002
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Bellevue, WA
Sep 14, 2006
#2
  • Sep 14, 2006
  • #2
24's shouldn't cause your bucking. You can run "too big" injectors without drivability issues, as long as your MAF is matched.

19's would probably be fine for your combo, but 24's shouldn't hurt you.

I'd be looking at your MAF for your bucking ussues. What kind of MAF are you running, and are you certain it is calibrated for 24lb injectors?

Anyone else have any thoughts?

Jeff
 

Fett

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Nov 2, 2004
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Sep 14, 2006
#3
  • Sep 14, 2006
  • #3
JChalfan said:
24's shouldn't cause your bucking. You can run "too big" injectors without drivability issues, as long as your MAF is matched.

19's would probably be fine for your combo, but 24's shouldn't hurt you.

I'd be looking at your MAF for your bucking ussues. What kind of MAF are you running, and are you certain it is calibrated for 24lb injectors?

Anyone else have any thoughts?

Jeff
Click to expand...

No, I'm not thinking that the 24s are too big...I am thinking that the 24s in my car are not all good. One or more may be having problems. I don't have a new set of 24s to try, the only thing I have is a new set of 19s and my stock MAFS.

The MAFS in my car is a pro-m that is calibrated for 24lb injectors.
 

90blacknight

Member
Apr 11, 2006
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Sep 14, 2006
#4
  • Sep 14, 2006
  • #4
I would have the 24's tested at a local shop.
 

JChalfan

Member
Nov 27, 2002
551
0
16
Bellevue, WA
Sep 14, 2006
#5
  • Sep 14, 2006
  • #5
Ah, got it.

I think 19's would work fine with your setup. I had a '94 cobra motor with e303 cam, 1.7RR's, explorer intake, 190lph pump, 65mm TB, 73mm MAF, and 19lb injectors. They worked great, and pulled strong to 6k. I didn't have any indication I was running out of fuel.

So I think you would be fine if you put your old injectors and MAF back in and see if that solves your problem.

If you have access to another 24lb calibrated MAF, I would swap that in real quick just to rule out your MAF being faulty.

Jeff
 

WHITE94COBRA

New Member
Nov 14, 2003
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HUNTINGTON BEACH
Sep 14, 2006
#6
  • Sep 14, 2006
  • #6
If it was a 94 cobra motor it should have had #24 injectors, the cobra's came with the larger injectors.

JChalfan said:
Ah, got it.

I think 19's would work fine with your setup. I had a '94 cobra motor with e303 cam, 1.7RR's, explorer intake, 190lph pump, 65mm TB, 73mm MAF, and 19lb injectors. They worked great, and pulled strong to 6k. I didn't have any indication I was running out of fuel.

So I think you would be fine if you put your old injectors and MAF back in and see if that solves your problem.

If you have access to another 24lb calibrated MAF, I would swap that in real quick just to rule out your MAF being faulty.

Jeff
Click to expand...
 

JChalfan

Member
Nov 27, 2002
551
0
16
Bellevue, WA
Sep 14, 2006
#7
  • Sep 14, 2006
  • #7
WHITE94COBRA said:
If it was a 94 cobra motor it should have had #24 injectors, the cobra's came with the larger injectors.
Click to expand...

Yes, but I didn't get the injectors, MAF, or intake with the motor. I used my old injectors. This was in a '90 5.0.

Jeff
 
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