1980-1982 4.2 V8 to 5.0 V8 swap

gonzo.ayres

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OK so I have spent the last hour online trying to figure this out with no solid info on the 4.2L V8. There is a 1980 Mercury Capri RS for sale, with said 4.2L V8, that I am very interested in picking up. As most of us know 1980 into mid 1982 the Ford fox platform had the 4.2L V8 ... not the 5.0 engine in. My question is about doing a 5.0 swap. Is a 5.0 swap just pulling the 4.2 drivetrain and dropping in the 5.0 drivetrain? Do they have the same mounting points, bell housing, etc? Another question is would it just be better to do a Maximum Motorsports tubular K member swap with the 5.0 set up and set it up that way? I do plan to build a street and mild track build. Thanks in advance!
 

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2Blue2

will be trying this sex one when I can find it
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Is a 5.0 swap just pulling the 4.2 drivetrain and dropping in the 5.0 drivetrain? Do they have the same mounting points, bell housing, etc?


Aloha from Waipahu.

Not much written on the 1980 255ci small block ford.

The 255 specifications are virtually the same as 302 with the exception of the bores. They were reduced to 3.68 inches and unnecessary cast iron was removed to make 255 lighter. Not a great performance block choice.

the 255 uses the standard 302 connecting rod and cranks are interchangeable

So yes it is very interchangeable for a 5.0 high output bad boy engine. Get one and just bolt it in.
I vote for a 363 dart long block, just saying :D
Really digging that quad eye RS capri, so flipping killer!

The tube k member is a neat part. There are a couple on install threads here if you dig around.
PS... Still got the Cobra 2 right?
 
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MustangIIMatt

Easy there, this ain't a dating site.
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Flywheel will be different, (assuming you're going with a later 302 with 50oz imbalance) but that's it. The 50oz imbalance flywheel is cheap and readily available too.
 
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Mstng93SSP

You have a nice rear end there Dave.
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Have you been to see the Capri? He has a lot of other cars too. He has a 93 yellow summer edition which I thought about picking up but the cowl rust was an issue for me. The Capri is nice, but I would have washed it personally before putting up the ad.

Chris
 
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Rcdgl

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Any 302 will literally bolt in where the 4.2 came out of. I started my 82 with a 4.2 from an 80 Capri years ago. Used all the v8 trinkets, crossmember, throttle linkage, front engine dress and brackets, etc. The 4.2 should have come with a c4 or c5 auto or a stick, and the 302 should bolt up. NOte that the 4.2 is a 50 oz balance, like a 5.0, so make sure you use all later 5.0 stuff or all early 289-302 stuff 79 or earlier.
 
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gonzo.ayres

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Aloha from Waipahu.

Not much written on the 1980 255ci small block ford.

The 255 specifications are virtually the same as 302 with the exception of the bores. They were reduced to 3.68 inches and unnecessary cast iron was removed to make 255 lighter. Not a great performance block choice.

the 255 uses the standard 302 connecting rod and cranks are interchangeable

So yes it is very interchangeable for a 5.0 high output bad boy engine. Get one and just bolt it in.
I vote for a 363 dart long block, just saying :D
Really digging that quad eye RS capri, so flipping killer!

The tube k member is a neat part. There are a couple on install threads here if you dig around.
PS... Still got the Cobra 2 right?

thanks for the info. yes i still have my cobra ii but i am actually selling it to pick up and build a fox for Circuit Hawaii that is being built!
 

gonzo.ayres

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Have you been to see the Capri? He has a lot of other cars too. He has a 93 yellow summer edition which I thought about picking up but the cowl rust was an issue for me. The Capri is nice, but I would have washed it personally before putting up the ad.

Chris

i have not yet gone to look. i really wanted to get the 83 t-top gt he had but he sold it before i could get my hands on it. he only has the capri and 1 other vert left. there are a few other foxes online but they are all modified or too far gone to restore
 

gonzo.ayres

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May 25, 2018
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Any 302 will literally bolt in where the 4.2 came out of. I started my 82 with a 4.2 from an 80 Capri years ago. Used all the v8 trinkets, crossmember, throttle linkage, front engine dress and brackets, etc. The 4.2 should have come with a c4 or c5 auto or a stick, and the 302 should bolt up. NOte that the 4.2 is a 50 oz balance, like a 5.0, so make sure you use all later 5.0 stuff or all early 289-302 stuff 79 or earlier.

that is great news. i will be building a motor (some variant of a fox 5.0). the capri sadly has an auto but i already have a T5 from a 95 mustang GT ready to rebuild that will be going in. I am not a pro with engines so I will have to do some digging with the balance and all that with whatever motor I get. i have a feeling that there are a lot of threads here to assist with that
 

FoxChasis

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As most of us know 1980 into mid 1982 the Ford fox platform had the 4.2L V8 ... not the 5.0 engine in.
1980-82 V8 engines in the "Fox platform"...

Fairmont/Cougar
1980 = 4.2L
1981 = 4.2L
1982 = no V8

Capri/Mustang
1980 = 4.2L
1981 = 4.2L
1982 = 4.2L and 5.0L (both all year)

Cougar/Thunderbird
1980 = 4.2L and 5.0L (both all year)
1981 = 4.2L and 5.0L (both all year)
1982 = 4.2L

Granada
1981 = 4.2L
1982 = 4.2L

Continental
1982 = 5.0L

The 4.2 should have come with a c4 or c5 auto or a stick
In the Capri and Mustang the 4.2L came with a C4 in 1980 and 1981 and a C5 in 1982.
In the other Foxes listed above the 4.2L either came with a C4 or an AOD, or both in the same year,

The 4.2L did not ever come with a manual transmission.
 
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SLeggi

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Aloha gonzo, I just picked up the Capri a few days ago. It's a 40 year old time capsule! The car is completely stock except he replaced the stock carb and tires. Interior is in in excellent/near-mint condition, just smells musty. Carpet looks and feels new, not soiled at all. Guy washed off the car and brought it back to his home where he washed it off. Paint is mostly still real good with with very small chips flaking off. No scratches, just swirls. Clearcoat is still excellent, absolutely no fading or chalking. Guy also included the original TRX wheels with the original tires still on them. And no rust on the car. No dings, no dents at all. So glad I got it. You missed out on an absolutely rare find, esp in Hawai'i. It's a true barn find! Aloha // SL
 
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