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Topic: 1985 t-bird 390 swap (Read 7395 times) previous topic - next topic

1985 t-bird 390 swap

i know a 351/302 will fit nicely in it but what about a 390.  i have a lead on a 69 mustang 390 with a c-6 trans.  can i still use a v-8 k-member from a v-8 t-bird/mustang? or is there something totally diffrent i have to do.  i took rough measurements and it looks like it will clear the shock towers. not sure about exhaust and trans.  i dont want to have to do alot of chopping of firewalls and things.  and will a aftermarket k-member be better for this as opposed to a factory k-member.  it would be nice to keep it as factory looking as possible.  any help will be appreciated...thanks

1985 t-bird 390 swap

Reply #1
Physically it should fit. I've seen plenty of 429/460 engines in Fox chassis cars, and FE series engines are smaller and lighter than those. Although where you get motor mounts to fit an FE to a Fox K-member, I have no idea.

1985 t-bird 390 swap

Reply #2
Headman headers used to have to fox body header swap header. Truck double sump oil pan and a engine plate would get you there.
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

1985 t-bird 390 swap

Reply #3
I seem to remember seeing a 390 swap a few years back. I think it was on this forum. Later, when I get time, I'll search for it.
CoogarXR : 1985 Cougar XR-7

1985 t-bird 390 swap

Reply #4
One of the guys local to me posts on here every so often has a race car with a big block, I think its a 83-84 T-bird. His username is 83-86Tbirdguy or something close.

EDIT- here is his profile: http://www.foxtbirdcougarforums.com/member.php?1670-83-88T-Bird-Guy

1985 t-bird 390 swap

Reply #5
Quote from: Drewstang;440283
One of the guys local to me posts on here every so often has a race car with a big block, I think its a 83-84 T-bird. His username is 83-86Tbirdguy or something close.

EDIT- here is his profile: http://www.foxtbirdcougarforums.com/member.php?1670-83-88T-Bird-Guy

FYI guys:

A 390 is a FE series big block ford, which is a completely different engine than a 385 series (460) big block Ford.
88 Thunderbird LX: 306, Edelbrock Performer heads, Comp 266HR cam, Edelbrock Performer RPM intake, bunch of other stuff.

1985 t-bird 390 swap

Reply #6
Why...?

Big. Heavy. Slug.
Long live the 4-eyes!  - '83 Tbird Turbo

1985 t-bird 390 swap

Reply #7
I don't know about "slug"...they take a little more money to make decent power, but are absolute torque monsters.  I'd say in a street/strip type build it would be pretty cool and best of all DIFFERENT.

I'm working on a '73 Ford truck right now that came with a 360 FE.  It had thrown a rod before I got it.  I've got it torn down now and the plan is to stroke it using the Survival Motorsports "prison break" 445 kit.  Granted mine will be more of a truck/torque monster build with iron heads, but a ton of classic Mustang and Cobra guys still use the FE series motors.  I'm hoping mine will make close to 400 hp...

Go to youtube and search for survival motorsports or Barry R.  He's got some really neat builds on there doing dyno pulls.  He also competes in the Car Craft Engine Masters Challenge every year.
'88 'bird, 10.9:1 306 w/TFS top end, forged rods/pistons, T-5 swap & bunch of other stuff, 1-family owned, had it since ‘98, 5.0tbrd88 on Instagram and YouTube

1985 t-bird 390 swap

Reply #8
As far as Ford big blocks go I would rather have a 385 big block over a FE. I would want a big, heavy powerful slug. Unless you have a 428 Cobra Jet or 427 side oiler the FE is a slug with any factory parts. Yeah to can swap to modern aluminum heads on a FE but do the same on a 385 series and it will stomp the  out of the FE.
88 Thunderbird LX: 306, Edelbrock Performer heads, Comp 266HR cam, Edelbrock Performer RPM intake, bunch of other stuff.

1985 t-bird 390 swap

Reply #9
I like oddball stuff, so I'm still sticking to the FE!  I like the idea of whipping up on 385 guys and bbc guys with a "slug", lol!
'88 'bird, 10.9:1 306 w/TFS top end, forged rods/pistons, T-5 swap & bunch of other stuff, 1-family owned, had it since ‘98, 5.0tbrd88 on Instagram and YouTube

1985 t-bird 390 swap

Reply #10
Why not just go with a stroked out Windsor. You can, with the right block, take one out to 427 cubes...and still be physically (externally) the same size as a 351w.

The 429/460 is nice, if I were going to do it, I'd go with a 390 though. mounts will be the biggest headache, and what transmission are you wanting. A C6 will be a tight fit, but with a 460, you'll have the same hassle.
I've got a set of 460 mounts for a Mustang k-member. That was as far as I got before I decided to junk out that car.

To do anything with a 460, you're going to want to upgrade the heads and intake, whereas even with an early 70's truck motor, the heads still flow decently.

Get a crank, bore it, and make it a real beast. ;)
'84 Mustang
'98 Explorer 5.0
'03 Focus, dropped a valve seat. yay. freakin' split port engines...
'06 Explorer EB 4.6

1985 t-bird 390 swap

Reply #11
You do realize a '69 Mustang with a factory 390 is a pretty odd bird? Why molest it and remove the 390 to make a mutt? Any pics of said 'Stang?
88 TC 5speed, 168000+ miles, stock 2.3T long block, ported RFE6 exhaust, Evergreen T3 running 15#'s.
Up next: FMIC, fresh air intake, ported intakes, ported big valve head.

1985 t-bird 390 swap

Reply #12
^What he said.
'84 Mustang
'98 Explorer 5.0
'03 Focus, dropped a valve seat. yay. freakin' split port engines...
'06 Explorer EB 4.6

thanks.....

Reply #13
Quote from: ThunderbirdSport302;440442
Why not just go with a stroked out Windsor. You can, with the right block, take one out to 427 cubes...and still be physically (externally) the same size as a 351w.

The 429/460 is nice, if I were going to do it, I'd go with a 390 though. mounts will be the biggest headache, and what transmission are you wanting. A C6 will be a tight fit, but with a 460, you'll have the same hassle.
I've got a set of 460 mounts for a Mustang k-member. That was as far as I got before I decided to junk out that car.

To do anything with a 460, you're going to want to upgrade the heads and intake, whereas even with an early 70's truck motor, the heads still flow decently.

Get a crank, bore it, and make it a real beast. ;)


thanks for the info.    i really wanted a 351w since they came with a 302 the fit is pretty much the same. just happened that i got a free 390 that ran well when in the last car.  all i need is a carb and couple odds n ends.  and a cam (its got a granny in it....just for highways). i ended up finding that summit has k members built specifically for what someone wants to do, with in reason.....they can do one for 3-500 buck and will have all mounts in the proper places.  also can take original suspension or after market parts.  still not positive i am gonna do it or not but really leaning towards it.  thanks again!!

1985 t-bird 390 swap

Reply #14
wasnt my stang and the guy wanted a 427,8,9 motor.  he was trying to trade it for my '51 ford to trade for the motor he wanted but it fell thru.  i totally agree about leaving the stang as it came (other than maybe hopping it up a bit)