86 3.8l to 5.0 Swap

Cole S

New Member
Oct 13, 2020
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Florida
I am looking to pick up an extremely clean 3.8l 86 mustang lx. It is in immaculate condition with one owner. It has a good price tag and has everything I would want except the 5.0 v8... So my question is what are the years compatible with that platform. What is required for each year? I know it is easier to just get the 5.0 mustang from the get-go and not to worry about the 3.8 but this ride is cleannnn. Anyways I have been doing research and I figured out that some fords of the time use the same engine setup as the mustang so what would those be? Any specific year to stay away from? I have looked up and it seems like the k frame will line up. Should I just buy an entire donor car? I heard about the 86 having flat top pistons so upgrades to the internals of the engine are limited without excess parts to be added. A lot of questions ik.
My plans for the build are very minimal and not high performance. I just want the classic v8 80s inefficient fuel-burning rumble car.
Side note- I also have a 01 Cherokee and everything is very straight forward for dummies like me, but this is a new ball game for me!
I am new to this form so I am sorry if this is not the right place to post this.
 
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General karthief

wonder how much it would cost to ship you a pair
Mod Dude
Aug 25, 2016
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polk county florida
The easiest way to do this (in my opinion) would be to get a 86 V8 mustang and swap EVERYTHING over to the 3.8 car.
Now what would I do? Get a V8 mustang to play with and drive the 3.8 car.
 

Cole S

New Member
Oct 13, 2020
2
0
1
17
Florida
The easiest way to do this (in my opinion) would be to get a 86 V8 mustang and swap EVERYTHING over to the 3.8 car.
Now what would I do? Get a V8 mustang to play with and drive the 3.8 car.
I would totally do that but my family already had 3 cars one bring a big van so that is not an option.
 

Mustang5L5

i'm familiar with penetration
Mod Dude
Feb 18, 2001
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Massachusetts
Technically anything in the 79-04 range will be compatible and can be swapped. If you had a donor 04 cobra, you could swap the engine/trans/IRS and even interior into the car. Obviously this is a more advanced swap.

The EASIEST swap in which you would have everything ready to go and require the least "chasing" of little odds and ends would be to find a 1986 V8 car and use that as a donor.

If you start to piece it together buy buying things separate, you will pull your hair our chasing all the misc one-year only wiring harnesses and brackets and such.

You could use an 87-93 as a donor, but not you will need to swap more harnesses and such from the donor as ford made wiring changes after 1986.
 

General karthief

wonder how much it would cost to ship you a pair
Mod Dude
Aug 25, 2016
17,853
5,796
193
polk county florida
Technically anything in the 79-04 range will be compatible and can be swapped. If you had a donor 04 cobra, you could swap the engine/trans/IRS and even interior into the car. Obviously this is a more advanced swap.

The EASIEST swap in which you would have everything ready to go and require the least "chasing" of little odds and ends would be to find a 1986 V8 car and use that as a donor.

If you start to piece it together buy buying things separate, you will pull your hair our chasing all the misc one-year only wiring harnesses and brackets and such.

You could use an 87-93 as a donor, but not you will need to swap more harnesses and such from the donor as ford made wiring changes after 1986.
Don't forget the dash is all different too
 

90sickfox

I didn't really have an issue with the stink...
SN Certified Technician
Mar 2, 2015
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The cheapest way would be to buy a 5.0 and drop it in with an 86 V8 computer and engine wiring harness.

I had a 84 3.8L mustang. That car cruised really well. I actually liked that little v6. They were good engines...just not a lot of power.

Is this car stick or auto ? If it's stick it'll be a lot easier to swap.

To be honest...in your case it may be better to go carbureted. One of my cars got 26mpg on the highway with an Edelbrock 600cfm carb. You'd need the engine...carb intake...carb...fuel pump...fuel pressure regulator...vacuum advance distributor....etc. I think the 3.8 and the 5.0 share the same bolt pattern for the transmission but that transmissions shift points will make a dog out of a 5.0...unless it's 5 speed.

If its clean and cheap...buy it already !!! Or tell us where it is and someone here will buy it.
 
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