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5.0 HO EFI on 289

  • Thread starter Thread starter broncobran68
  • Start date Start date Mar 26, 2004
B

broncobran68

New Member
Mar 18, 2004
20
0
0
Mar 26, 2004
#1
  • Mar 26, 2004
  • #1
I am putting an 87 EFI setup from a stang on a 68 289 and need verification that this is correct: To account for firing order differences, 13... on HO and 15.... on 289, I just switch the #3 cylinder injector with the #5 injector and the same with the #7 and #4. I am on a very tight budget and want to avoid the 351w cam swap.

Brandon
 

ashford

Member
Dec 19, 2003
485
0
16
fargo ND
Mar 27, 2004
#2
  • Mar 27, 2004
  • #2
in theory that should work but it might give you a little trouble with the o2 sensor readings since your changing between banks

the one biggest problem you may have is the front coolant passages, the later engines(80 up i think it is) the coolant passage is about 3/16s of an inch away from the front bolt holes and the older engines this area is exposed. the gasket will barely cover the passage about a 1/16s of an inch to nothing, check it out before you get commited.
 

Håkan

Founding Member
Apr 1, 2002
168
0
0
Enköping, Sweden
Mar 28, 2004
#3
  • Mar 28, 2004
  • #3
Yes, it will work. I am not sure about just moving the connections, when I converted my 289 I cut, reconnected, soldered and covered the wires in the injector harness with heatshrink tubing.



Have more info about the swap here: http://www.vikingmustang.com/EFI_01.asp
 

blue66tang

Founding Member
Jan 20, 2001
1,092
0
0
Medford, OR
Mar 28, 2004
#4
  • Mar 28, 2004
  • #4
I always thought you just had to swap the spark plug wiers around, but i dont know much about the efi setups.
 

rbohm

Founding Member
Apr 12, 2002
6,698
550
204
tucson,az
Mar 28, 2004
#5
  • Mar 28, 2004
  • #5
the 5.0 harness will work fine on a 289 as you stated by changing the firing order on the injectors. when you extend the wires, solder them well. also the should be no problem with the intake on the 289 as they really didnt change the bolt pattern or intake gasket patterns over the years. oh and you neednt worry about O2 sensor problems as they just sense the amount of oxygen in the exhaust stream. instead of changing the injector firing order, i suggest changing the cam to the 5.0 cam, that way you can take advantage of the later cam engineering designed for efi.
 
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