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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • 1994 - 1995 Specific Tech

Gt Computer in a Cobra?

  • Thread starter Thread starter scottmrit
  • Start date Start date Oct 8, 2006

scottmrit

New Member
Feb 24, 2004
18
0
2
Oct 8, 2006
#1
  • Oct 8, 2006
  • #1
I have a 1994 cobra that has a tm40 in it. My cobra gets about 215 to a

tank and i am sure that the computer doesn't like the 24lb injectors. I

purchased a used j4j1 on ebay and my car idles and drives better with the tm

40,a lot better.

I think the j4j1 was DOA, so my options are get j4j1 rebuilt at ecudirect.com

(cost 200). Then i just have a stock j4j1, or do i purchase a chip that will

take care of the injectors. I am leaning towards a chip so i get some

performance out of it. If i get a chip do i need one for a j4j1 or do i need one

for a tm40?
 

BlownFiveLiter

have car, will race....wait, it doesn't run
15 Year Member
Nov 29, 1999
3,133
18
108
Chicagoland
Oct 8, 2006
#2
  • Oct 8, 2006
  • #2
The Cobra came from the factory with 24lb injectors, so that shouldn't be an issue. Did you try pulling codes at all? 215 miles to a tank doesn't sound too far off. The best I ever got out of my GT was somewhere around 230-240, and that was all highway miles.
 

scottmrit

New Member
Feb 24, 2004
18
0
2
Oct 8, 2006
#3
  • Oct 8, 2006
  • #3
This is a cobra engine being ran by a gt computer(tm40). The tm40 is setup to run 19lb injectors so it thinks i am running rich, so it is adjusting causing my mpg to be off.
 

BlownFiveLiter

have car, will race....wait, it doesn't run
15 Year Member
Nov 29, 1999
3,133
18
108
Chicagoland
Oct 8, 2006
#4
  • Oct 8, 2006
  • #4
Ah, I get what you're saying now... If you have any performance mods in your future, you might want to look into getting something like a TwEECer for a couple hundred more than the new computer will run you. Then you can just load up the J4J1 file for the Cobra and tune as necessary from there.
 

blksn955.o

Founding Member
Mar 15, 2002
3,263
0
66
st.louis mo 314
Oct 8, 2006
#5
  • Oct 8, 2006
  • #5
WTF???

How is that thing even running? I tried to run my car on the stock gt eec. My combo is 95 cobra heads, exploder intake (gt40), 24lb inj, and a TFS cam and it at most will idle for 15seconds with a stock gt eec running things. I had basicly the same combo with 19's and the stock eec and it ran ok but I just dont see how your even getting it to idle
 

final5-0

Mustang Master
Apr 6, 2003
6,817
12
79
DFW Texas
Oct 8, 2006
#6
  • Oct 8, 2006
  • #6
You gotta be too fat as the pcm is pulsing inj's it thinks are 19's but in reality are 24's.

I can see how you could get by with that mismatched setup.

Only thing that makes me wonder how you did it was .........
the first few times you drove it ......
it took a while for the adaptive to peg full lean ......

I bet those first few drives were really nasty

Self tune, pro tune, or get the correct pcm

Grady
 
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