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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
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engine identification question

  • Thread starter Thread starter garystocker
  • Start date Start date Jul 6, 2005

garystocker

Member
Jan 2, 2005
305
0
17
New Jersey
Jul 6, 2005
#1
  • Jul 6, 2005
  • #1
I have a rebuilt engine in my 87 5.0. They told me later it may be a 1986-93 in there. Now I don't know which year engine I have.

How can I visually identify the year to determine if I got stuck with a 86 with the flat top pistons and restrictive heads...

The issue is important as the plugs for the 86 vs. the 87 are the same thread but one stick into the cylinder waaaay farther. I worry of putting in the wrong longer plug and having an exposed thread cause detonation, or worse the piston smashes it.

help
 

87MustangGT5.0

Member
Apr 16, 2003
153
0
17
Maryland
Jul 6, 2005
#2
  • Jul 6, 2005
  • #2
Who rebuilt the engine, you or the last owner? I so not see why somebody would swap the 87 motor for a rebuilt 86.
 

garystocker

Member
Jan 2, 2005
305
0
17
New Jersey
Jul 6, 2005
#3
  • Jul 6, 2005
  • #3
I didn't WANT to swap an 87 for an 86!

I went to Engine World because they promised me a 1987 5.0 HO for 1100 installed.

Then when I did a tune up and couldn't get my plugs to fit in the head I called them up and asked what they hell they gave me.

They told me it could have been any year: 86-93 and 86 had different heads.

Now I need you guys to tell he how to tell if I have an 86 or 97-93 engine under my hood!
 

87MustangGT5.0

Member
Apr 16, 2003
153
0
17
Maryland
Jul 6, 2005
#4
  • Jul 6, 2005
  • #4
Do you have ay idea if the car was swapped from a 4 cylinder to a 5.0 or if it is an original 5.0? This could make the difference because if it came already a V8, then they probably would have just pulled it out and rebuilt it. If it was a swap, then there is a lot more of a chance being an 86 motor.
 

garystocker

Member
Jan 2, 2005
305
0
17
New Jersey
Jul 6, 2005
#5
  • Jul 6, 2005
  • #5
It was a swap. About 5 years ago my vibration damper came off my 1987 LX 5.0 and that rattled my rotating assembly into oblivion.

I then, (being poor) sought out the cheapest way to retain my 5.0 and get my daily driver runnin'.

So I then find out the happy news it might be a 1986.

How can I tell...there must be a way!
 
1

1989MustangLX

New Member
Apr 7, 2005
118
0
0
Canada
Jul 6, 2005
#6
  • Jul 6, 2005
  • #6
You could always try getting the plugs for an 86 5.0, and see if they fit. Simple way to do it.
 

z9_87

New Member
Apr 16, 2004
332
0
0
Urbana, IL
Jul 6, 2005
#7
  • Jul 6, 2005
  • #7
Yeah get the casting numbers off of it, I'm sure that would tell. Right?
 
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