Build Thread 1978 Fairmont. I bet somebody back home’s thinkin’…I wonder why he don’t write..?

my mini's were 12-15#
 

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Because I have zero sense of what I can get done in an allotted amount of time.

Today I’m laying out the plan,…Do I want to finish the dash and paint it, :chinor Drop the rear end for the gear change, :chinor Install the starter, and steering shaft, fill the transmission, and put the tunnel back in place.:chin
or…
Do I want to fabricate the rear tail shaft mount so that I can remove the jack stand that’s there holding the trans up.:chin

Hell,…maybe I can paint the dash, and while it’s drying, install the starter, and reinstall the steering shaft, then fill the transmission, ( since you can literally see the fill plug from above now that the tunnel is out) and put the tunnel back in place.
When that’s done, I’ll fab up the trans crossmember. I mean, how long could all this sht actually take?:shrug:

So at 8:30, I set out to get what I need.
I go to oreillys to get 5 qts of gear oil, and the paint for the dash. ( cept they don’t got no paint) But I got my oil.
I need steel to build the crossmember, Metal Supermarket is only 10 minutes past O Reilly’s.
I get my steel.
On the way back, I stop at Home Depot to get the bolts to hold my future crossmember.
I get my bolts.
Advance is right next door, I have to go there to get the paint that oreillys didn’t have.
I get my paint.
I stop off at Chick-fil-A to get breakfast.
I get breakfast.
When I get home it’s almost 10. I start out building the crossmember.
At 2 I stop to eat.
I’m still building the crossmember.
At 4 I let the dog (puppy) out of his pen, and let him run around awhile. I go back downstairs 30 minutes later so I can continue building the crossmember.
At 6, I’m done building the crossmember.
:nonono:
I don’t know….maybe I’m slowing down..Maybe things like a completely fabricated crossmember mounted to the floor through a piece of 1/8” plate just happens to take all freakin day. Maybe I made the thing way more complicated than it had to be.
Or….
Maybe I just suck at estimating what I can, or can’t get done in a day.
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When I first built this car, I welded 8x8 pieces of 1/8” plate to the sides of the tunnel. The crossmember bolts through that plate, and is made up of more 1/8” plate underneath.
The center section drops out, and the legs that bolt to the floor remain. But they too can be unbolted should I decide to do that.
On a Fox body Mustang, the rear trans mount is a chunk of heavy stamped steel that bolts to the subframes. You are going to be making a lot more power than most Fox body Mustangs, and yet you bolted the trans mounts into the floor pan with no visible reinforcement. I would believe that it won't take much spirited driving before cracks start to radiate from the bolt holes used to hold the crossmember you made. The engine torque will try to move the transmission around and that will easily overstress what you have built.

At a minimum, you need a 1/16" doubler plate on the outside and inside of the the car. The doubler plate needs to be 1" wider on the top and bottom., and 2" longer on each end of the doubler plate. Weld it in place and you will be good to go; you will spread the stress over a much wider area and reduce the tendency to crack.
 
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On a Fox body Mustang, the rear trans mount is a chunk of heavy stamped steel that bolts to the subframes. You are going to be making a lot more power than most Fox body Mustangs, and yet you bolted the trans mounts into the floor pan with no visible reinforcement. I would believe that it won't take much spirited driving before cracks start to radiate from the bolt holes used to hold the crossmember you made. The engine torque will try to move the transmission around and that will easily overstress what you have built.

At a minimum, you need a 1/16" doubler plate on the outside and inside of the the car. The doubler plate needs to be 1" wider on the top and bottom., and 2" longer on each end of the doubler plate. Weld it in place and you will be good to go; you will spread the stress over a much wider area and reduce the tendency to crack.
I’m pretty sure he did that-
04190AA9-45B4-489E-854D-BB2376250F19.jpeg
 
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Mike, I’ve done more 8.8 gear swaps than I can remember. It’s super simple... an old racer taught me a trick. DO NOT use a new crush sleeve! Take your old pinion and sleeve to an anvil or brick, etc and hammer the side of the sleeve while rotating on the pinion. This lengthens the old sleeve. It’s softer than a new sleeve, 100x easier to crush, and won’t budge after installing. It saves TONS of effort and works fantastically. New sleeves are so hard to crush you’ll hurt yourself or something else crushing them. I also don’t bother retrieving the old shim, as long as you use Ford gears drop a .020 shim under the new pinion bearing and go. Keep your carrier shims (L&R) in order and everything goes right back in place, every time. I use a new pinion nut with thread locker and zap the nut with an impact a little at a time to crush the sleeve, checking preload by hand until it’s close. I can usually nail it as to when checked with a baby torque wrench it’s right. I did my first 3 or 4 checking preload torque. I don’t bother now. Never had an issue either. I would suggest checking preload on your first venture, however. I honestly can’t remember the spec on inch lbs.. you’ll have to search that.

edit: The caveat here is swapping Ford gears for Ford gears. If you do that, your checks (depth and backlash) will fall into place every single time. Not so much with Yukon or Richmond gears. That is a nightmare. I refuse to use them at all anymore.
A few questions from someone who is also looking to do their own gears in the future:

1. Are the Ford Performance gears that are currently available also able to be used like this?

2. Would you recommend staying away from used gear sets?

3. If not, do the same rules above apply to used Ford gear sets as well?
 
A few questions from someone who is also looking to do their own gears in the future:

1. Are the Ford Performance gears that are currently available also able to be used like this?

2. Would you recommend staying away from used gear sets?

3. If not, do the same rules above apply to used Ford gear sets as well?
1- Yes

2- No, as long as they aren’t chipped or grooved rock on. I’ve used lots of used gears, no issues ever. In fact, I just put used 3.73s in my vert out of an explorer.
3- same rules apply for used gears. Keep your carrier shims with the carrier and just move the ring gear over.

Hope that helps! If you have any installation questions, I’m happy to help however I can!
 
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1- Yes

2- No, as long as they aren’t chipped or grooved rock on. I’ve used lots of used gears, no issues ever. In fact, I just put used 3.73s in my vert out of an explorer.
3- same rules apply for used gears. Keep your carrier shims with the carrier and just move the ring gear over.

Hope that helps! If you have any installation questions, I’m happy to help however I can!
I appreciate it! I have three sets of gears I want to do in the near future.
 
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On a Fox body Mustang, the rear trans mount is a chunk of heavy stamped steel that bolts to the subframes. You are going to be making a lot more power than most Fox body Mustangs, and yet you bolted the trans mounts into the floor pan with no visible reinforcement. I would believe that it won't take much spirited driving before cracks start to radiate from the bolt holes used to hold the crossmember you made. The engine torque will try to move the transmission around and that will easily overstress what you have built.

At a minimum, you need a 1/16" doubler plate on the outside and inside of the the car. The doubler plate needs to be 1" wider on the top and bottom., and 2" longer on each end of the doubler plate. Weld it in place and you will be good to go; you will spread the stress over a much wider area and reduce the tendency to crack.
Re-read the first part where i stated that I welded an 8x8“x1/8” plate on both sides of the tunnel where that crossmember is bolted through joe.

And in every case…
The rear crossmember on a fox Mustang is a flimsy piece of stamped 18 gauge steel that can easily be twisted in a vise with minimal effort. Couple that to the equally flimsy, almost always bent to hell floor mounted 18 ga. ( at best) crossmember mounting flange.

Im quite confident that an 8x8” plate welded to the tunnel is more than sufficient to hold the transmission in place, especially considering the solid mounted front mounts for the engine.
 
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Mike, I’ve done more 8.8 gear swaps than I can remember. It’s super simple... an old racer taught me a trick. DO NOT use a new crush sleeve! Take your old pinion and sleeve to an anvil or brick, etc and hammer the side of the sleeve while rotating on the pinion. This lengthens the old sleeve. It’s softer than a new sleeve, 100x easier to crush, and won’t budge after installing. It saves TONS of effort and works fantastically. New sleeves are so hard to crush you’ll hurt yourself or something else crushing them. I also don’t bother retrieving the old shim, as long as you use Ford gears drop a .020 shim under the new pinion bearing and go. Keep your carrier shims (L&R) in order and everything goes right back in place, every time. I use a new pinion nut with thread locker and zap the nut with an impact a little at a time to crush the sleeve, checking preload by hand until it’s close. I can usually nail it as to when checked with a baby torque wrench it’s right. I did my first 3 or 4 checking preload torque. I don’t bother now. Never had an issue either. I would suggest checking preload on your first venture, however. I honestly can’t remember the spec on inch lbs.. you’ll have to search that.

edit: The caveat here is swapping Ford gears for Ford gears. If you do that, your checks (depth and backlash) will fall into place every single time. Not so much with Yukon or Richmond gears. That is a nightmare. I refuse to use them at all anymore.
Just to check that I’m reading you right, you’re removing the old pinion with the existing bearing on it still, and installing a new bearing onto the new pinion with a .020 shim. Flattening out the old crush sleeve enough to allow it to preload the bearing when reinstalling, and then sliding that dude onto the new pinion and putting it in place using a new nut.

Are you re-using the existing races from the old bearing?
 
This is what i’m talking about..
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Seemingly good from far….but
Far from good.
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I think they call this solvent pop..paint under didn’t get a chance to adequately flash off before i shot a second coat.
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And there’s this…good old contaminated substrate,…something on the surface that the paint i sprayed on top didn’t like and reacted.

And this is what I gotta accept. Especially now that these new layers of an enamel paint have been added to the already substantial base layers. Firstly, attempting to sand and spray a rattle can top coat is full of peril, as there is a fairly long cure time before that can be attempted w/o running the risk of the whole freaking thing wrinkling. Second, there’s already a buttloads of paint on the thing as it is.

If i knew for sure that there wasn’t any body filler in these parts, ( dash, console, door bars) i’d just take this stuff and have it powdercoated, but i don’t know/remember where it is for sure. I’m pretty sure it’s there though.
Even if I do, Ill just fck that up trying to get the mesh on.
Defying Karma, I went ahead and wet sanded the dash bars to smooth out the solvent pop and the fish eyes. Prepped the thing again with wax and grease remover twice, all while wearing rubber gloves, and remembering not to touch my face/hair while handling the whole mess.

Then I lightly sprayed the bars with a first coat, and watched, and waited for a paint reaction.

Nothing……So i gave it 5 more minutes, and sprayed one medium wet coat, and went inside so I wouldn’t be tempted to spray it again too quickly.

When I came out, it was wrinkling in a few places. I knew that I would be wasting my time adding more paint and it would just aggravate the wrinkling if i did, so I bailed on the project for the night and left it.

I argued with the notion of just having the thing powder coated again, but after having wet sanded it this last time, I could plainly see that I had added body filler to the tops and bottoms of the curved portion of the dash bars. Powdercoating would require sandblasting, and that filler would get blasted away, leaving whatever mess that was under the filler exposed, and then amplified with the brand new satin black powder coat.

This morning, I go back out to the bars now that they have had the evening to cure…The wrinkling has shrank back, and is no longer noticeable, but…..It needed another coat of paint.

Im at the fck it stage…I’m installing the dash bars as is.
 
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Just to check that I’m reading you right, you’re removing the old pinion with the existing bearing on it still, and installing a new bearing onto the new pinion with a .020 shim. Flattening out the old crush sleeve enough to allow it to preload the bearing when reinstalling, and then sliding that dude onto the new pinion and putting it in place using a new nut.

Are you re-using the existing races from the old bearing?
Bingo. Just make sure the bearings are the same angle. Those Ford Racing install kits use Chinee bearings with different angled races. Find a timken or National pinion bearing.

Heat your bearing in the oven at 225 degrees for about an hour and just drop it on the pinion. Don’t exceed 250 degrees, that’ll ruin it.
 
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Bingo. Just make sure the bearings are the same angle. Those Ford Racing install kits use Chinee bearings with different angled races. Find a timken or National pinion bearing.

Heat your bearing in the oven at 225 degrees for about an hour and just drop it on the pinion. Don’t exceed 250 degrees, that’ll ruin it.
Uhh, that doesn’t tell me the Answer Allen. There is probably a Koyo bearing on the existing pinion. The bearing that I have new is a Koyo bearing. Do i leave the races in the housing if that’s the case.
And i have a HF press, I don’t need to heat the new one. And i can pull the old one off just as well.
 
Uhh, that doesn’t tell me the Answer Allen. There is probably a Koyo bearing on the existing pinion. The bearing that I have new is a Koyo bearing. Do i leave the races in the housing if that’s the case.
And i have a HF press, I don’t need to heat the new one. And i can pull the old one off just as well.
Okay, my apologies, let me try to clear that up. If you have a like for like branded bearing, yes... use the old race. I have actually mixed National brand with Timken and they were good, I wouldn’t try that with any other brands. If it was running fine and doesn’t show signs of damage it’s ok. The thing about good bearing companies is, they hold their tolerances so precisely, you practically never see any variance between bearings of the same make. The only time I’ve ever seen that happen is with Chinese bearings. Since you do are working with Koyos, I would pull the old pinion bearing and retrieve that shim just to be safe and use it under the new pinion bearing, or at least one the same thickness. Also, any time you press on a new bearing in lieu of heating it, you run the risk of damaging the cage or a roller. Just not worth it. In the industry we very, very seldomly press on new bearings. 99% of the time we use an induction heater. An oven is an excellent alternative. Hope that helps, don’t hesitate to ask if I overlooked answering part of your question again, lol.
 
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Okay, my apologies, let me try to clear that up. If you have a like for like branded bearing, yes... use the old race. If it was running fine and doesn’t show signs of damage it’s ok. The thing about good bearing companies is, they hold their tolerances so precisely, you practically never see any variance between bearings of the same make. The only time I’ve ever seen that happen is with Chinese bearings. Since you do are working with Koyos, I would pull the old pinion bearing and retrieve that shim just to be safe and use it under the new pinion bearing, or at least one the same thickness. Also, any time you press on a new bearing in lieu of heating it, you run the risk of damaging the cage or a roller. Just not worth it. In the industry we very, very seldomly press on new bearings. 99% of the time we use an induction heater. An oven is an excellent alternative. Hope that helps, don’t hesitate to ask if I overlooked answering part of your question again, lol.
One more thing, which may not need to be said, but I’m going to throw it out there... Any time you press a bearing off of a pinion, carrier, shaft, etc... NEVER reuse it. Throw it away.
 
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Ok, I think I’m in the right mental place to start the gear change over. For whatever reason, and for the first time in about a year, I slept till like 9:45.
( It’s like I’m a college student or something) :jester:
I’m leaving the dash bars “ as is”. I’m thinking about trying to relocate the tweeters to the top corners of the dash bars that look a little dry, as that is the only place I could possibly find fault with, and if they’re covered, I don’t see that anymore.
But that’ll leave holes, and impressions where they used to be 2” above that on the leather part of the dash.
And yet another eyesore that I’ll focus my gaze upon.
 
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Well it’s on…Gear-n-dectomy 101.
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A keen eye (for those of you that have them) will notice the lack of upper C/A mounts, and the goofy metal bars that make up the support mounts for my GM style Torque arm.
I removed the axles.
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The bearings on the 9” ends don’t want to slide through the backing plate, so I just remove them as units.
I made the tool to hold the pinion flange..
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removing everything was pretty easy comparatively…I left the rear sway bar in place to act as a stop so the freakin carrier wouldn’t just roll out on me. ( it didn’t)
When I got the pinion out, I opted to press the bearing off because I wanted to see what brand bearing was on it. It came off really easy.
So easy in fact that I decided to re use both the existing shim and that bearing and pressed them onto the new pinion. ( which also went on easy)
I checked the crush sleeve to see what thickness it had crushed to, and compared that to a new one .450 versus .480.
.030 diff.
Didn’t seem like getting a new crush sleeve to crush .030 would be that big a deal, but I knew from experience that it was, so I employed the @Boosted92LX recommended method of flattening the old crush sleeve to put thickness back in it so that it would be “ easier” to get it to crush.
So I put the thing back into the housing, put my bonafide pinion flange tool on, zipped a new nut down as far as my weak-assed HF 1/2” cordless impact would tighten it to, and then went about the process of trying to tighten that nut tight enough to crush that sleeve.
* If anybody knows where I can find a new left nut, please PM me.
Nothing I have was up to the task.
Every HF breaker bar I had was a joke. while they didn’t break, there was enough deflection to severely limit how far I could push/pull the bar. The 24” long bar had a rubber handle and I couldn’t slide the jack handle over it, and while I could slide that jack handle over the 18” bar,…the car was too close to the ground to let me get it where I needed it.
I decided to get the “man” out…My3/4” torque wrench that I use to torque that freakin harmonic balancer bolt on that requires 275 ft lbs.
I set it to 300 ft lbs and pull it with all my might…..movement.
I ck the pinion preload. Registers 0.
I pull the thing again, and again it moves…
4” pounds.
I pull it one more time and it moves once more.
18” pounds.
A little on the tight side for a used bearing, but I can’t back it off, so I gotta leave it where it is.
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So that’s done. Hopefully I’ll not have to take the bitch back apart due to a bad pattern, but I’m halfway there.
The dash bars have been in the sun for 3 days now. The heat did the paint alot of good.
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I believe I can live with them.
 
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I’ve said it here before. If you buy carpet from ACC, you are paying way too much.
1B2631AD-E6D3-4D9C-8283-F0B2B146AFF4.png

This is from their website.
When you google Auto carpet, these guys come up too.
C9EDE044-A61C-431B-A7CA-80DEB0647A89.png

Guess what?…..both carpets come from the same company.

So, i’m gonna take a chance here…I planned to do a total custom carpet that looks like the mach 1 sets that you see above, but I got to thinkin’.
“ I wonder how far apart the 69 mustang set is from the 79 fairmont set? If anything, I’d imagine that a 69 mach 1 is a bigger car than my little fox, so at worse case, i split the set in the middle of the tunnel, cut out the “ too much”, and take it to my upholstery guy to seam back together.
On the other hand, if it just won’t freakin work at all I can always ship it back. ( or just get in my car, and take it back to Anniston where it’s made)
So for 250.00 shipped, I ordered the black set with the saddle inserts..Allows me the opportunity to change out my carpet color w/o totally bailing on my existing interior color scheme.

Just remember next time you buy carpet, and now you have an extra couple of hundred in your back pocket to thank me.
 
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I’ve said it here before. If you buy carpet from ACC, you are paying way too much.
1B2631AD-E6D3-4D9C-8283-F0B2B146AFF4.png

This is from their website.
When you google Auto carpet, these guys come up too.
C9EDE044-A61C-431B-A7CA-80DEB0647A89.png

Guess what?…..both carpets come from the same company.

So, i’m gonna take a chance here…I planned to do a total custom carpet that looks like the mach 1 sets that you see above, but I got to thinkin’.
“ I wonder how far apart the 69 mustang set is from the 79 fairmont set? If anything, I’d imagine that a 69 mach 1 is a bigger car than my little fox, so at worse case, i split the set in the middle of the tunnel, cut out the “ too much”, and take it to my upholstery guy to seam back together.
On the other hand, if it just won’t freakin work at all I can always ship it back. ( or just get in my car, and take it back to Anniston where it’s made)
So for 250.00 shipped, I ordered the black set with the saddle inserts..Allows me the opportunity to change out my carpet color w/o totally bailing on my existing interior color scheme.

Just remember next time you buy carpet, and now you have an extra couple of hundred in your back pocket to thank me.
I doubt you’ll be happy with how it is molded. I do not think the floor pans are interchangeable. Not that your floor pans are still entirely stock shape, but you should have some major steaming to get it to fit.
 
I doubt you’ll be happy with how it is molded. I do not think the floor pans are interchangeable. Not that your floor pans are still entirely stock shape, but you should have some major steaming to get it to fit.
Whatever are you talking about Willis? All it’s gotta be is close enough to “make” it fit.
If, dimensionally it’ll fit and leave me enough overlap to trim it, I’ll cut the bulges/ excess out and have it sewn back together if I can hide that surgery under the console.
 
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