Will a 1991 5.0 Fuel tank and lines fit into a 1986 5.0?

[MustangOwner]

Hey guys,
Is there any reason why a '91 5.0 fuel tank and lines wouldn't fit a 1986 5.0? THanks!

[svo6]

No reason. Should be the same.

[shovelhead 93]

neck could be different had it happen to me big hole little hole.

[TurboBeater]

i put a 92 fuel tank and lines in my 83. The 87+ uses a different fuel sending unit though. Your fuel gauge will not read correctly with the 91 sending unit. You'll have to use the sending unit from a car made in 86 or earlier for the gauge to work properly. I still have the 92 sending unit and the gauge reads "E" instead of "F" when full, and doesn't start to move until there's only about 1/4 of a tank left.

[eric5oh]

Originally Posted by TurboBeater

i put a 92 fuel tank and lines in my 83. The 87+ uses a different fuel sending unit though. Your fuel gauge will not read correctly with the 91 sending unit. You'll have to use the sending unit from a car made in 86 or earlier for the gauge to work properly. I still have the 92 sending unit and the gauge reads "E" instead of "F" when full, and doesn't start to move until there's only about 1/4 of a tank left.

X2 Other than the sender, it is all the same

[TWR2003]

All 83-97 CFI/EFI tanks are the same.

All 86+ EFI fuel lines are the same.

As mentioned fuel gauge sender is unique to 83-86 with either CFI or EFI. That is because its compatible with 79-86 fuel guage AND 83-97 CFI/EFI tank - the overlap is 83-86.

T

[Drew Schofield]

Originally Posted by TWR2003

All 83-97 CFI/EFI tanks are the same.

All 86+ EFI fuel lines are the same.

As mentioned fuel gauge sender is unique to 83-86 with either CFI or EFI. That is because its compatible with 79-86 fuel guage AND 83-97 CFI/EFI tank - the overlap is 83-86.

T

Not to hijack the thread, but the 79-85 carb tanks have one hole for the sending unit and the feed and return hoses. And the 85-up EFI tanks have 2..right? 1 for fuel, 1 for the gauge sending unit. If I wanted to go efi on my 85, can I just get a 86-up tank and put my gauge sending unit in it, plugging the fuel lines..welding them up?

Is there anything dimensionally different about the 86-up EFI tanks from my 85 carb tank or will it bolt in?? Are the straps or the plastic covers different?

[Dean_T]

Originally Posted by Drew Schofield

Not to hijack the thread, but the 79-85 carb tanks have one hole for the sending unit and the feed and return hoses. And the 85-up EFI tanks have 2..right? 1 for fuel, 1 for the gauge sending unit. If I wanted to go efi on my 85, can I just get a 86-up tank and put my gauge sending unit in it, plugging the fuel lines..welding them up?

Is there anything dimensionally different about the 86-up EFI tanks from my 85 carb tank or will it bolt in?? Are the straps or the plastic covers different?

I think the older fuel sending unit and pickup has a larger mounting flange (which means a larger hole in the tank) than the CFI/EFI fuel sending unit. I can check but I'm sure they don't interchange. A bummer because even here in Southern Cal it's getting hard to find a yard that doesn't yank the tank before releasing the car to the bone jackers.

Dean T

[TWR2003]

Originally Posted by Drew Schofield

Not to hijack the thread, but the 79-85 carb tanks have one hole for the sending unit and the feed and return hoses. And the 85-up EFI tanks have 2..right? 1 for fuel, 1 for the gauge sending unit. If I wanted to go efi on my 85, can I just get a 86-up tank and put my gauge sending unit in it, plugging the fuel lines..welding them up?

Is there anything dimensionally different about the 86-up EFI tanks from my 85 carb tank or will it bolt in?? Are the straps or the plastic covers different?

Responding to your hikjack:

All 81-97 (yes 97) Mustang fuel tanks are phsically interchageable but there were two sub types made:

81-86 with carb: The tank only has one large hole for the sender and its in the 'tall' part of the tank on the drivers side

81-86 Carb tank (Spectra Premium F-12A)


81-85 Carb senders
w/o return (Laurel Mtn: FM-EF040)


with return (Laurel Mtn: FM-EF040B):



83-97 with EFI: The tank has two large holes, one for the sender and one for the fuel pump. But the sender on these tanks now mount in the 'short' hole near the tank center. The fuel pump fits in the 'tall' section now.

83-97 EFI tank (Spectra Premium F-12B)


83-86 EFI sender (LRS: LRS-9275A)


So if you want to convert to EFI you will need the 83-97 tank, the 83-86 sender, and a 86+ fuel pump assembly. Sorry, you will not be able to use your 'carb' sender in the EFI tank.

Good luck,
T

[Drew Schofield]

Thanks for the great info!!! One question...do you know if the sender can be taken apart and put on the 87-up sender? If not, then I need a 86 sender..right? Does anyone repop these?

Originally Posted by TWR2003

Responding to your hikjack:

All 81-97 (yes 97) Mustang fuel tanks are phsically interchageable but there were two sub types made:

81-86 with carb: The tank only has one large hole for the sender and its in the 'tall' part of the tank on the drivers side


So if you want to convert to EFI you will need the 83-97 tank, the 83-86 sender, and a 86+ fuel pump assembly. Sorry, you will not be able to use your 'carb' sender in the EFI tank.

Good luck,
T

[mfpmax]

You can find some E3ZC part #s senders...not sure if they are repro but I believe someone supposedly is. They will run you $80-100 to buy them.

[TWR2003]

Originally Posted by Drew Schofield

Thanks for the great info!!! One question...do you know if the sender can be taken apart and put on the 87-up sender? If not, then I need a 86 sender..right? Does anyone repop these?

1. Im not sure I understand what you want to do - take apart a fuel sender???. Please explain better.

2. Forgive my ignorance (or it it old age) but what is 'repop'?

3. The 87+ fuel sender has a different resistance curve and is not compatible with the 79-86 fuel guage. As I started previously the 83-86 sender you need is available from Late Model Resto:
http://www.latemodelrestoration.com/...0%201&comp=LRS

T

[mfpmax]

Repop is reproduction

Yes I beleive they are talking about swapping the resistance wire and wiper assembly to the later model sender to make it work. Not sure if that would, i've read of one or two people that modified their stock senders, but they never had pictures or detailed explanation.

[Drew Schofield]

Originally Posted by mfpmax

Repop is reproduction

Yes I beleive they are talking about swapping the resistance wire and wiper assembly to the later model sender to make it work. Not sure if that would, i've read of one or two people that modified their stock senders, but they never had pictures or detailed explanation.

Hopefully if/when I get to that point, I can find someone with a good 86 sender. Looks like $100 bucks for a new one...$110 for a new tank...$100 for a new pickup...$100+ for a new fuel pump...dang this fancy efi setup is getting expensive!!

[mfpmax]

Yup, my setup only consists of a new possibly NOS sender, and junkyard tanks and "junkyard" fuel lines from a buddies swapped 4 cylinder(I have a 2.3 Turbo converted from carb). The Sender being the most expensive, lines and tank were less than $40 total.

[TWR2003]

Originally Posted by Drew Schofield

Hopefully if/when I get to that point, I can find someone with a good 86 sender. Looks like $100 bucks for a new one...$110 for a new tank...$100 for a new pickup...$100+ for a new fuel pump...dang this fancy efi setup is getting expensive!!

$300+ for tank, pump, and sender sounds about right for new parts. Are you are considering a full SEFI conversion? You are just getting started. There is a lot more you will need although for alot of it you can go used: intake (upper and lower), injectors/rails, sensors, harnesses, EEC computer, etc. Im very wary of used sensors though. Used harnesses can be fine or junk and its hard to tell without stripping them down which is ALOT of effort. Remember, used harnesses are at least 15 years old now. Life in the engine compartment of a 5.0L Mustang for 15 years is harsh.

With a good mix of some used and new parts you are probably looking at $800-$1000 plus your effort to install. Swapping harnesses from a 87+ into a 85 is not plug and play so be prepared for that too.

You may want to consider buying a wrecked 87+ Mustang for its parts.

Search FEP using key words like 'EFI conversion', etc for info. Thats what I did.

T