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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • Fox 5.0 Mustang Tech

2.3 to 5.0 swap issues in an 88

  • Thread starter Thread starter 5.0ina66
  • Start date Start date Jul 8, 2009
5

5.0ina66

Member
Jun 6, 2003
664
0
16
Ohio
Jul 8, 2009
#1
  • Jul 8, 2009
  • #1
My dimwit brother in-law who "likes to work on cars" but has the mechanical skills of a goldfish just bought an 88LX that was 5.0-swapped. Took it for a spin to go get his other car because he left it at the guy's house when he bought the Mustang and I started finding problems with the damned thing before we got out of his driveway...why did I promise to help work on it?

Now, I'm a classic mustang guy, but I read some stickies about doing the 5.0 swap a couple years ago so I'm not totally helpless, but I've forgotten most of it, so am going to need some help! They didn't totally FUBAR the poor car, but they could have done a better job, especially with the electrical.

First thing is that the tach reads way too high...I'm assuming they used the 4cyl cluster, but I know some clusters have dip switches to set-up the tach. Not sure we can use that or what? Weird thing is the huuge Autometer tach does the same thing and I don't remember how to set those up either??

Second, it's supposed to have a cammed up 306 in it. Not sure I believe that, looks pretty stock, but it idles crappy, surges a little and stuff like that. Probably need to investigate that tomorrow before I can really ask for help on getting it to stop doing that. If it really is a built motor (which is a scary thought here in hickville) I expect it will need a tune to run worth a crap.

Cruise doesn't work and AC is broke too, plus the belt squeals like a pig 24/7.

I'm gonna be asking a lot of questions as we sort this pig out and start modding it, so any tips or advice you can give right now will undoubtedly help.
Thanks
--Kyle
 

old_blue

15 Year Member
Nov 3, 2003
1,783
282
124
Jul 9, 2009
#2
  • Jul 9, 2009
  • #2
Sometimes they route the belt wrong to where it only goes underneath the crank pulley (like contacting maybe an 1/8 of the pulley) instead of going around almost 3/4 of the way. Jrichter will hopefully chime in with the idling checklist. good luck
 

stykthyn

I want to measure mine. It doesn't look that tall.
15 Year Member
Jul 6, 2006
5,232
2,652
223
gainesville
Jul 9, 2009
#3
  • Jul 9, 2009
  • #3
check the surging idle checklist.

find out what year ECU is in the car. is it mass air or speed density. if it is cammed it may need to be tuned. if its a mass air car it should be ok though.
 
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