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Help with 1985 5.0 HO EFI Mustang

  • Thread starter Thread starter Belliott85
  • Start date Start date Apr 25, 2022
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    1985 cfi lx 5.0
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Belliott85

New Member
May 14, 2019
6
0
1
Delaware
Apr 25, 2022
#1
  • Apr 25, 2022
  • #1
Good evening all. I'm looking for some guidance on a direction for my recently purchased 1985 convertible. Found a great deal on an all factory unmolested 1985 LX convertible with a factory 5.0 and AOD trans. It has the EFI motor and only 58K original miles. While it's definitely a time capsule. it has been in storage for a very,,..very long time. I have spent the last couple days going through the car listing out what needs to be done. The car runs and drives however it has a very hard to press gas pedal(as in its hard to push down, then breaks through and surges like you jumped on pedal). It also runs a bit rough. I checked the OBD1 and i get a code for EVAP, which isn't a surprise because just about everything rubber on the car is toast.

My question for you guys. Has anyone converted their old school for CFI to a new style EFI like a holley sniper system. if so how did you go about it as far as intake, distributor, ignition and fuel pump. how about a carb conversion? I want to keep this vehicle as close to stock as I can while updating it some for driveability. I plan to make it a family cruiser nothing that will be raced or wild. I was thinking cleaning up the engine bay, dumping a lot of this old school tech and making it fresher while adding some poneys would be a cool driver. Thoughts?
 

TOOLOW91

If you're the village idiot what's that make me?
20+ Year Stangneter
Nov 29, 1999
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Apr 25, 2022
#2
  • Apr 25, 2022
  • #2
Belliott85 said:
Good evening all. I'm looking for some guidance on a direction for my recently purchased 1985 convertible. Found a great deal on an all factory unmolested 1985 LX convertible with a factory 5.0 and AOD trans. It has the EFI motor and only 58K original miles. While it's definitely a time capsule. it has been in storage for a very,,..very long time. I have spent the last couple days going through the car listing out what needs to be done. The car runs and drives however it has a very hard to press gas pedal(as in its hard to push down, then breaks through and surges like you jumped on pedal). It also runs a bit rough. I checked the OBD1 and i get a code for EVAP, which isn't a surprise because just about everything rubber on the car is toast.

My question for you guys. Has anyone converted their old school for CFI to a new style EFI like a holley sniper system. if so how did you go about it as far as intake, distributor, ignition and fuel pump. how about a carb conversion? I want to keep this vehicle as close to stock as I can while updating it some for driveability. I plan to make it a family cruiser nothing that will be raced or wild. I was thinking cleaning up the engine bay, dumping a lot of this old school tech and making it fresher while adding some poneys would be a cool driver. Thoughts?
Click to expand...
If you choose to do the Holley - DO NOT use the sniper . Get a 4150 stealth terminator x .

Use a Holley dual sync dist with a hidden 6al ( for factory look ) and it will run like a charm. If you didn’t want to use the dual sync you could even get away with a 87-93 TFI dist and then not have to use a 6al ignition box.
 
B

Belliott85

New Member
May 14, 2019
6
0
1
Delaware
Apr 25, 2022
#3
  • Apr 25, 2022
  • #3
TOOLOW91 said:
If you choose to do the Holley - DO NOT use the sniper . Get a 4150 stealth terminator x .

Use a Holley dual sync dist with a hidden 6al ( for factory look ) and it will run like a charm. If you didn’t want to use the dual sync you could even get away with a 87-93 TFI dist and then not have to use a 6al ignition box.
Click to expand...
Awesome Ill check that out. Would i need to change to a different intake manifold or will the factory work with that unit?
 

TOOLOW91

If you're the village idiot what's that make me?
20+ Year Stangneter
Nov 29, 1999
8,483
8,687
234
S.I.NY
Apr 26, 2022
#4
  • Apr 26, 2022
  • #4
Belliott85 said:
Awesome Ill check that out. Would i need to change to a different intake manifold or will the factory work with that unit?
Click to expand...
I’m not familiar with the 85 cfi intakes but if it’s a 4BBL intake like I think it is, it’s zero issue .
 
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