1998 v-6 engine in a 1966 mustang does anyone know if this has been done

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rbohm

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Apr 12, 2002
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its about as hard as any other engine swap. as i recall the essex V6 uses the same motor mounts as the early 289/302, at least where they bolt to the block. the bell housing bolt pattern is the same as the 289/302 so that engine will bolt up to the transmission, but you will have to get the right flywheel/flexlate. my advice for that is to get the transmission that comes with the V6, usually a version of the AOD, which means you need AOD conversion mount/crossmember. if the AOD you get is the electronic version you will need a trans controller. and if you plan to run the factory EFI, you will need all the attendant wiring and fuel system components to make it work. plus all the other little details necessary to complete a swap on any nature.
 

rssumbler

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its about as hard as any other engine swap. as i recall the essex V6 uses the same motor mounts as the early 289/302, at least where they bolt to the block. the bell housing bolt pattern is the same as the 289/302 so that engine will bolt up to the transmission, but you will have to get the right flywheel/flexlate. my advice for that is to get the transmission that comes with the V6, usually a version of the AOD, which means you need AOD conversion mount/crossmember. if the AOD you get is the electronic version you will need a trans controller. and if you plan to run the factory EFI, you will need all the attendant wiring and fuel system components to make it work. plus all the other little details necessary to complete a swap on any nature.
Thank you for you help . I have the whole car so I can take whatever is needed to make it work. Thank you again
 

rbohm

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remember the hardest part if going to be dealing with the wiring harness. there are wires you will not need. so get yourself a comprehensive wiring diagram and study it carefully.
 

MARKDTN

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See my post update on full 5.0 Explorer swap. The key to an ODB2 swap into an early car (after being sure it physically fits) is programming the PCM. Look for "the EFI guy" in Colorado. Garry can program the EEC IV and V PCMs to remove PATS, fuel tank codes, etc. This is the key to a no SES light on conversion. With a good wiring diagram manual and some ciphering it could be done-especially with a complete donor car. Sounds like the mechanical side is not that difficult.
 

rbohm

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See my post update on full 5.0 Explorer swap. The key to an ODB2 swap into an early car (after being sure it physically fits) is programming the PCM. Look for "the EFI guy" in Colorado. Garry can program the EEC IV and V PCMs to remove PATS, fuel tank codes, etc. This is the key to a no SES light on conversion. With a good wiring diagram manual and some ciphering it could be done-especially with a complete donor car. Sounds like the mechanical side is not that difficult.

i forgot about the PCM conversion as well. OP if you dont want to go through all that expense, then check out these two sites, they have a lot of stuff for the essex V6, including stroker kits to bump things up to 4.2l;



and then head over to holley.com for the EFI stuff, including complete systems that you can use on your V6 and not deal with the wiring harnes issues and the PCM reprogramming issues.
 

wicked93gs

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I suppose it depends on what exactly your goal is with the v6. The essex v6 is going to be just as much effort as a SBF 5.0L EFI engine but offering little benefit over a 5.0L except maybe fuel mileage and a slightly better weight balance. Of course there are any number of perfomance upgrades you can do to the engine....such as the supercharged 3.8L from a T-bird supercoupe, or any of the Tom Morana stuff....but really, just because you have a donor car is not a reason to use a given engine...you will spend more and get less than from an equivalent SBF swap...or even from a modified I6. If you want to do it for the challenge and fun, go right ahead(that is why I swapped in the 3.7L myself) but if you are building toward a certain goal, I would reconsider the engine choice.
 
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rbohm

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personally i like the essex V6 over the later 3.7 based engines. but to each their own.
 

wicked93gs

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personally i like the essex V6 over the later 3.7 based engines. but to each their own.

They are certainly more compact. I once saw a Chrsyler Conquest in a junkyard with a 3.8L Supercharged swap.....with a turbocharger as well...a twincharged oddball swap...was probably the strangest junkyard find ever.
 

rbohm

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They are certainly more compact. I once saw a Chrsyler Conquest in a junkyard with a 3.8L Supercharged swap.....with a turbocharger as well...a twincharged oddball swap...was probably the strangest junkyard find ever.

i dont even care about the size of the engines, they both fit the vintage engine compartments well enough to use them. my issue is with the way the waterpump is driven on the ecoboost engines. best hope you dont get a coolant leak because it will destroy the ecoboost engines in short order, since likely you would never know the leak was there until it was too late. and wile you are there, assuming you catch the problem early enough, you may was well replace teh timing chain and its attendant parts, gears tensioners, etc.
 

wicked93gs

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i dont even care about the size of the engines, they both fit the vintage engine compartments well enough to use them. my issue is with the way the waterpump is driven on the ecoboost engines. best hope you dont get a coolant leak because it will destroy the ecoboost engines in short order, since likely you would never know the leak was there until it was too late. and wile you are there, assuming you catch the problem early enough, you may was well replace teh timing chain and its attendant parts, gears tensioners, etc.

Yeah, not the best design.....but just think of it as part of a 70k maintenance package and you are golden, besides, the issue with the water pump was addressed in a TSB and the replacements last far longer. Anything is better than the 20k maintenance on a 3.0/3.2 SHO engine though....beautiful engines, but high maintenance...far better just mild timing stuff.
 

rbohm

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yea the SHO engines are quite high maintenance to be sure. and the essex is not without its problems also. it likes to eat head gaskets especially on the early engines. the later ones cured that issue.
 

MustangIIMatt

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personally i like the essex V6 over the later 3.7 based engines. but to each their own.
The 3.8L Essex has half the horsepower and the same fuel economy combined with sounding like a tractor? No thanks. The 3.7 is far superior, it sounds like a European or Asian V6, makes insane power for it's displacement, and still gets fantastic fuel economy.
i dont even care about the size of the engines, they both fit the vintage engine compartments well enough to use them. my issue is with the way the waterpump is driven on the ecoboost engines. best hope you dont get a coolant leak because it will destroy the ecoboost engines in short order, since likely you would never know the leak was there until it was too late. and wile you are there, assuming you catch the problem early enough, you may was well replace teh timing chain and its attendant parts, gears tensioners, etc.
There are two versions of the 3.5/3.7 Duratec/Cyclone family. In front-wheel-applications, you have the dreaded timing-chain-driven water pump that dumps coolant into the oil. The rear-wheel-drive versions from the F150 and Mustang do not, they have "traditional" water pumps mounted to the outside of the cover. I've done the timing covers on both versions (and water pumps, and chains, and cam phasers). Hell, I've even done a 3.5 water pump, in a Taurus, in my driveway.


Yeah, not the best design.....but just think of it as part of a 70k maintenance package and you are golden, besides, the issue with the water pump was addressed in a TSB and the replacements last far longer.
The replacements are crap too in the FWD applications. The change to running a double-gear on the water pump pulley didn't help much.
 

wicked93gs

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The 3.8L Essex has half the horsepower and the same fuel economy combined with sounding like a tractor? No thanks. The 3.7 is far superior, it sounds like a European or Asian V6, makes insane power for it's displacement, and still gets fantastic fuel economy.

There are two versions of the 3.5/3.7 Duratec/Cyclone family. In front-wheel-applications, you have the dreaded timing-chain-driven water pump that dumps coolant into the oil. The rear-wheel-drive versions from the F150 and Mustang do not, they have "traditional" water pumps mounted to the outside of the cover. I've done the timing covers on both versions (and water pumps, and chains, and cam phasers). Hell, I've even done a 3.5 water pump, in a Taurus, in my driveway.



The replacements are crap too in the FWD applications. The change to running a double-gear on the water pump pulley didn't help much.


Really? I was under the impression the RWD engines had both an internal and external water pump. I haven't actually taken the front cover off of mine to find out though(only 15k miles on the engine), just read that somewhere. It would be a relief to just have a 2 hour casual replacement rather than a timing-chain involved one.
 

MustangIIMatt

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Really? I was under the impression the RWD engines had both an internal and external water pump. I haven't actually taken the front cover off of mine to find out though(only 15k miles on the engine), just read that somewhere. It would be a relief to just have a 2 hour casual replacement rather than a timing-chain involved one.
The RWD engine's pump bolts to the timing cover. There's a coolant pipe that runs to it that the FWD versions don't have.
 
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