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Topic: Fox Mustang frame rails fit Fox Thunderbird/Cougar? (Read 1924 times) previous topic - next topic

Fox Mustang frame rails fit Fox Thunderbird/Cougar?

I just noticed Late Model Restoration sells replacement front frame rails for 79-93 Mustangs.

LH: https://lmr.com/item/LRS-FRLH780/1979-93-Mustang-LH-Oe-Style-Frame-Rail

RH: https://lmr.com/item/LRS-FRRH880/1979-93-Mustang-RH-Oe-Style-Frame-Rail

Would these be an option for a Fox Thunderbird/Cougar that needs rotted frame rails replaced? If the rails have the same dimensions between the two cars it would make frame repairs easier for Fox Thunderbird/Cougar owners.
88 Thunderbird LX: 306, Edelbrock Performer heads, Comp 266HR cam, Edelbrock Performer RPM intake, bunch of other stuff.

Fox Mustang frame rails fit Fox Thunderbird/Cougar?

Reply #1
I would *think* so since the Fox Bird/Cats are a direct evolution of the chassis, but I'd want Chuck or aerocoupe to weigh in to be 100% sure.

Personally, I think if LMR sold repop core supports, there'd definitely be money in that too. Would take a bodyshop or at least someone with experience in Fox and/or body work to put on...but...

And...Jerry, Jerry..Jerry. LOL
'84 Mustang
'98 Explorer 5.0
'03 Focus, dropped a valve seat. yay. freakin' split port engines...
'06 Explorer EB 4.6

Fox Mustang frame rails fit Fox Thunderbird/Cougar?

Reply #2
They sell complete 90-93 core supports, not sure what changed, id guess bumper shock absorber redesign for airbags.

They also sell the front half of the 83-89 core support, ya know, the part thst usually looks okay.
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

Fox Mustang frame rails fit Fox Thunderbird/Cougar?

Reply #3
Quote from: ThunderbirdSport302;459641
I would *think* so since the Fox Bird/Cats are a direct evolution of the chassis, but I'd want Chuck or aerocoupe to weigh in to be 100% sure.


I would *think* the frame rails would be the same. The cars are dimensionally identical from the strut towers to the firewall. Thunderbirds/Cougars might be longer forward of the strut tower.

On a side note I noticed some rust bubbles on the frame rails looking up through the front springs on both sides where the K-member meets the frame rail. You know, some place you wouldn't see unless the car is up in the air and you look through the hole in the bottom of the control arm :hick:. It's nothing bad but I'm sure there is internal rust in the frame at the frame rail/strut tower/K-member bolt plate meeting point. Water seems to get trapped in that area and rust from the inside out. I can see some internal scale (nothing on the outside) on the frame rails looking through the many, many holes Ford left in them. It doesn't surprise me as, after almost 30 years, it's bound to happen. Of course I'm already planning for 5 years down the road to have both frame rails replaced "just because it's not perfect". Probably end up being about $2-2.5k between parts and labor.
88 Thunderbird LX: 306, Edelbrock Performer heads, Comp 266HR cam, Edelbrock Performer RPM intake, bunch of other stuff.

 

Fox Mustang frame rails fit Fox Thunderbird/Cougar?

Reply #4
I would have to find my dimension specs of both cars to check
[SIGPIC][/SIGPIC]
***** Project "EVOLUTION" 1987 Cougar LS  & 1985 Cougar Convertible *****
[/COLOR]
5.0 HO 306 roller block, machined GT-40P heads, Wiseco dished forged pistons, Eagle forged floating I-beam connecting rods, Lunati pushrods, ARP bolts, Scorpion aluminum 1.6 rockers, Comp Cams Magnum 266HR, Explorer intake, 65mm TB, MAF Conversion, 19# injectors, Ford Racing stainless P-headers, 2-1/2" cat-less exhaust w/ Flowtech Afterburner lers , SC AOD with 2800 BDR torque converter, 3.73 T-Lok rear, CHE rear control arms, full 2-1/2" frame w/1" jacking rails & seat supports, Rear disk brakes, Turbine wheels, All original interior w/ floor shift upgrade .......
Pretty much every panel on my 87 is new, rebuilt, or re constructed. :D
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Fox Mustang frame rails fit Fox Thunderbird/Cougar?

Reply #6
Quote from: daminc;459651
I would have to find my dimension specs of both cars to check


Quote from: EricCoolCats;459652
I'm pretty sure they're the same...FWIW.


If you could check that would be cool.

With how rust free my car is I was surprised to see that dime size rust bubble where the k-member and frame rails meet. I reached my pinky finger into one of the factory frame holes and felt around. The crush sleeves and some of the internal parts of the frame rail felt crusty. So then I started tapping stuff with a ball peen hammer and everything was fine. But now I want to have the strut tower/frame rail meeting point cut opened and cleaned up at some point just because I'm crazy :hick:

The strut tower/frame rail meeting point kind of sucks. There is a gap at the corners. Any water or dirt that gets kicked up by the tires will fall in the gaps to the internal part of the frame. If it ever gets to the point where I get that section cut open I'm having the k-member bolt plate fully welded all around to keep gunk out.
88 Thunderbird LX: 306, Edelbrock Performer heads, Comp 266HR cam, Edelbrock Performer RPM intake, bunch of other stuff.

Fox Mustang frame rails fit Fox Thunderbird/Cougar?

Reply #7
this is the best I can do




[SIGPIC][/SIGPIC]
***** Project "EVOLUTION" 1987 Cougar LS  & 1985 Cougar Convertible *****
[/COLOR]
5.0 HO 306 roller block, machined GT-40P heads, Wiseco dished forged pistons, Eagle forged floating I-beam connecting rods, Lunati pushrods, ARP bolts, Scorpion aluminum 1.6 rockers, Comp Cams Magnum 266HR, Explorer intake, 65mm TB, MAF Conversion, 19# injectors, Ford Racing stainless P-headers, 2-1/2" cat-less exhaust w/ Flowtech Afterburner lers , SC AOD with 2800 BDR torque converter, 3.73 T-Lok rear, CHE rear control arms, full 2-1/2" frame w/1" jacking rails & seat supports, Rear disk brakes, Turbine wheels, All original interior w/ floor shift upgrade .......
Pretty much every panel on my 87 is new, rebuilt, or re constructed. :D
Join us on Facebook

Fox Mustang frame rails fit Fox Thunderbird/Cougar?

Reply #8
Quote from: daminc;459657
this is the best I can do





Looks like the Thunderbird/Cougar frame rails are slightly longer than the Mustang, if I'm interpreting that diagram correctly. I'm pretty sure someone could use Mustang fram rails in a pinch. You would just need to lengthen them slightly forward of the strut towers.
88 Thunderbird LX: 306, Edelbrock Performer heads, Comp 266HR cam, Edelbrock Performer RPM intake, bunch of other stuff.