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Topic: Straight 6 swap? (Read 5373 times) previous topic - next topic

Straight 6 swap?

Hello Everyone,

Just wondering how hard it would be to swap a 200 I6 into an 85' Cougar with a 3.8. Long ago I owned an 80' Mustang with an I6 in it and I know the Cougars are similar to the Mustang. I know I will have to switch over to carb and I am unsure if the tranny will work. If there is anything else ya'll can think of that would be great. Also should I consider one of the larger I6 engines 250 or 300.

BTW I have considered just dropping a 302 in it but my other Cougar already has that. Just wanna do something a little different.

Peace,
Dan
87' Mercury Cougar XR-7 5.0/AOD (DD)
85' Mercury Cougar GS 3.8/3-spd (project)

Straight 6 swap?

Reply #1
I've been looking for a BB capri, and was planning on trying to do the 200 Aussie crossflow trick, and see if it worked.  But alas, I didn't.  Nevertheless, the 300 won't likely fit.  The 250 is a similar version of the 200 but is taller, and will probably require hood-work.  The 250 also has the small block bell pattern.
1987 TC

Straight 6 swap?

Reply #2
300 i-6 has the sb bolt pattern as well. I am sure you could make a 300 fit, but god those things are long. Might have to stick with an automatic and move the shifter back a couple  of feet...

The motor mounts from a 200 i-6 should swap into a 79-93 mustang, or 83-85.5 cougar/bird k-member.

Overall, if you could find a dirt cheap rusted out 80's mustang with the engine and transmission, you could swap it out straight acrossed with probably few problems.
Quote from: jcassity
I honestly dont think you could exceed the cost of a new car buy installing new *stock* parts everywhere in your coug our tbird. Its just plain impossible. You could revamp the entire drivetrain/engine/suspenstion and still come out ahead.
Hooligans! 
1988 Crown Vic wagon. 120K California car. Wifes grocery getter. (junked)
1987 Ford Thunderbird LX. 5.0. s.o., sn-95 t-5 and an f-150 clutch. Driven daily and going strong.
1986 cougar.
lilsammywasapunkrocker@yahoo.com

Straight 6 swap?

Reply #3
If you fab your own oil pan and motor mounts u may be able to use factory  K-member... if not id suggest the early 80-82ish inline six k-member as it is unique for the straight six.  Just my 2 cents... oh yeah... i know where an inline six stang with 4 speed is :))

Straight 6 swap?

Reply #4
It would probably be easier to find a fairmont or zephyr with the I6. It's a fox, and I think that was the default motor for those cars. Just about every fairmont I see has the I6. A few days ago I posted a fairmont with a dead I6 I saw on craigslist in our leads section.
CoogarXR : 1985 Cougar XR-7

Straight 6 swap?

Reply #5
Quote from: the_intimidator03;274202
If you fab your own oil pan and motor mounts u may be able to use factory  K-member... if not id suggest the early 80-82ish inline six k-member as it is unique for the straight six.  Just my 2 cents... oh yeah... i know where an inline six stang with 4 speed is :))

Yup a I6 uses a unique K-member... You'll need to do some fabbin' if you can't find a parts car...


NOW... Without a power adder or maybe a good free flowing head the 200s are turds... I've owned several 200/auto Fairmonts and a '80 Stang with the 200 & 4speed... It was better than the NA 2.3 Stangs, but that's about all I can say for it... Stick it in a vehicle totin'  another 700-800Lbs and it wouldn't even qualify as a turd... You'll likely need the transmission as well, AFIK the 170/200/250 bolt pattern is all to it's self(you need to verify this)...  Possibly a Granada/Monarch 250cu in wouldn't be a terrible choice, but I read somewhere, Ford stated they were too tall to fit in the Fox engine bay...

Forget the 300 was even mentioned, way too tall to fit in a Fox engine bay without a scooped hood... Prob have to cut the firewall as well or set the radiator in front of the support...

Straight 6 swap?

Reply #6
Thanks for the advice folks, it is really helpful. I am very adamant about doing this engine swap. Actually after making this post I have already planned everything out for this car. Hopefully most of you will like what I have in mind for this project. I will make a post about it in the near future. Thanks again.

Peace,
Dan W
87' Mercury Cougar XR-7 5.0/AOD (DD)
85' Mercury Cougar GS 3.8/3-spd (project)

Straight 6 swap?

Reply #7
The later "BB" 200 block (with the starter low on the pass side), uses a 2/3 SBF bell pattern.
Long live the 4-eyes!  - '83 Tbird Turbo - '85 Marquis LTS - '86 LTD Wagon

Straight 6 swap?

Reply #8
Just my $.02, but if you go ahead with this, do it with your eyes open. Projects like this always sound cool because they are different. The downside is afterwards. Even assuming you figure everything out and it actually makes it to the road. When you try to sell it, you're going to have to give it away. I know you will say you already thought of that, I am just re-enforcing that fact. The reason you see so many 5.0 swaps is because so many guys like them. When you're done, you may have a "belly button" car, but you also have a large group of potential buyers. If you swap an I6 in, I am sure you will get lots of looks at the hamburger stand and guys on forums like this will think it's neat, just don't expect a lot of interest if you go to sell it. I am not trying to be a jerk as I think swaps like that are very cool. I just wouldn't want to buy it when it's done. Having said all of that, I am happy to see ANY Ford engine going in a Ford instead of a SBC (yuck). Whatever you decide, good luck!!
1987 Turbo Coupe - Son's car
1987 Super Coupe - Son's project car
1934 Ford - My project car

Straight 6 swap?

Reply #9
I think it would be a cool project with a 70mm turbo and a blow through carb.
1979 Ford Fairmont
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5.0L/4R70W/8.8"/5-lug/3" Exhuast


Straight 6 swap?

Reply #10
Dont look for *ANY* power unless you find an aussie head for it. Our heads have the intake/exhaust manifolds cast right into the head. And they are TINY. Engines were made for everything BUT power.
93 Festiva L, 193k miles, BP+T/G25MR swap, T3 50trim .48/.42, SRT FMIC, Capri electronics/Rocketchip, 2.5" exhaust
bests: ET 12.86, MPH 110.25, 1.92 short
02 Subaru Impreza WRX, 129k miles
97 Subaru Impreza Outback Sport, 236k miles

Straight 6 swap?

Reply #11
this is something I had always wanted to do also...but with an aussie cross-flow head and EFI from a MAF Taurus.  You should do it...then get bored of it and sell it to me for pennies on the dollar...lol.

Good luck, let us know how it goes,
-Don
Project 3G: Grandpa Grocery Getter-'85 Crown Vic LTD 2-door, 351W with heavily ported/polished GT40 heads, heavily ported/polished Typhoon Power Plus upper & lower intake, Comp Cams 265DEH retarded 1*, FAST EZ-EFI, HD T5, 8.8" 3.73 trac lock with extra clutches, 3G alt. swap, '99 CVPI front brakes, '09 CVPI rear disc brakes, '00 CVPI booster&m/c + wilwood adj prop valve.

Parted & Gone-'88 T-bird Sport, 351W swap, ported GT40 heads

Straight 6 swap?

Reply #12


No mods have been done yet, and the head is just sitting on the engine for storage at the moment, but I see no issues in the mods required to make it work.

The BIG expense, since I want to turbo it, is forged pistons...$700-800 for a set.
Long live the 4-eyes!  - '83 Tbird Turbo - '85 Marquis LTS - '86 LTD Wagon

Straight 6 swap?

Reply #13
it Chuck...do we have to live vicariously through you ALL the time? lol
Project 3G: Grandpa Grocery Getter-'85 Crown Vic LTD 2-door, 351W with heavily ported/polished GT40 heads, heavily ported/polished Typhoon Power Plus upper & lower intake, Comp Cams 265DEH retarded 1*, FAST EZ-EFI, HD T5, 8.8" 3.73 trac lock with extra clutches, 3G alt. swap, '99 CVPI front brakes, '09 CVPI rear disc brakes, '00 CVPI booster&m/c + wilwood adj prop valve.

Parted & Gone-'88 T-bird Sport, 351W swap, ported GT40 heads

Straight 6 swap?

Reply #14
Quote from: Sick88Tbird;276218
it Chuck...do we have to live vicariously through you ALL the time? lol


seems that way, dont it?
one of us should clean that head though......:rollin:
gumby - beauty may fade, but stupid is forever!