The Snot Rocket: Green '73 fastback

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giantpune

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I was shopping around for a parts car, and this one caught my eye. I went and picked it up today. It looks in good enough shape, I may end up keeping it and not tearing into it for parts.
Its a 73 fastback. Original paint color is booger green (4B paint code). The outside was painted a forest green with sparkles some time back in the 80s or 90s. If you look close, it looks like a DIY job, but not completely terrible. The door jambs and inside of the trunk lid are still booger green. Interior is avocado green. Its in OK shape. It will need carpet and a headliner for sure. All of the seats need some attention. The radio was swapped for as AM/FM cassette player at some point, and that still works.

Marti report says H code 351C, C6 transmission, open 2.75 rear. It has the power disc brakes, power steering, and all the AC parts appear to still be there. The body is in pretty decent shape overall. The cowl is rusted through. There are several spots in the passenger side floor pan rusted through. The bottom of the driver's door has a rust hole big enough for your fingertip when you open the door and feel around at the bottom. The battery tray is pretty rusted, too. The rest of the sheet metal looks pretty decent. The car has spent some time sitting outdoors. Underneath, there are vines that have grown to it. Most things under the car have a fair amount of surface rust.

Previous owner has put on a holley intake manifold and what look like a holley vacuum secondary 4 barrel carb. Gas tank is new. It has long tube headers connected to a pretty rough looking aftermarket exhaust with what looks like glass packs. Between the glass packs and all the exhaust leaks, it sounds pretty bad. It looks like most of the convoluted smog crap, vacuum lines, and tees are still there. Some are connected, some aren't. Kickdown linkage is present, but not connected to anything. I guess because the carb requires some special adapter for it.

The car currently runs and drives. It starts right up, with a little cloud of smoke that looks like fuel. It feels like it has double digit horsepower. I've ridden powerwheels that felt snappier than this. The transmission shifts like it should. The brakes all seem to work. Previous owner has done new lines and new calipers at least. And it seems like at least 90% of the lights currently work. The heater blows hot. I havn't tried the AC yet. The seat belt buzzer works sometimes. That may be down to the switch in the seat not working right. All the tires are holding air enough to drive around, but they are all dry rotted.

So thats where I'm starting on this guy.

First thing I did was take off the silly looking front license plate bracket and the antique Bill Elliot front plate.
I checked the engine out a bit. Initial timing is set at about 18 degrees. I can loosed up the distributor screw but the distributor itself didn't want to turn. And I didn't want to smack it with a hammer and break it the first hour I had it home.
I'm sure it will rustle some jimmies, but I swapped the vacuum advance over from ported to manifold vacuum. Then I played with the idle speed and mix screws to try and find the spot where the engine is happy. I'll play around with it and try and land on some combination of settings that makes this thing feel like it has more than 3 cylinders.

Next order of business is probably sort out the tires. I'm still debating if I want to keep rocking the factory 14" wheels and dog dish hubcaps, or buy a new set of rims.
After that will likely be pulling the carpet and seeing about the floor pan. And I need to do something about the cowl. I am not going to pull this car apart to weld in a new upper and lower cowl. I was thinking about some sort of blockoff plate for the top to keep water from coming in and rotting out the floor.

I would like to eventually do the body work and paint it back to its original snot green glory.

And if there's a way to remove the surface rust from the things under the car quickly, I'm interested. I was thinking to put it up on a lift, make a big plastic tent, and then start sandblasting or put a wire brush in a drill. I'm open to suggestions for how to do it fast and easy. :D

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It's never as fast of easy as you hope. That said, I recommend a Harbor freight 5" grinder with a wire brush basket attachment in the arbor. I used this for the surface rust on my interior and exterior floorboards. If the undercoating is tar based, bug and tar remover will soften it so you can use a paint scraper to remove it. Also get a comfortable creeper, as you will be spending a lot of time on it.
 
Heck of a nice looking parts car. I had the same dilemma with a 71 M-code Cougar. rotted to death, but I drove it for two years before it got totalled.

Undercarriage is just get in there and get dirty. I'd try some Simple Green and a pressure washer to knock the mess off, then suit up and a cup wire wheel on a 4.5" angle grinder. A couple coats of Rust Bullet and it'll be looking good. Build some wheel cribs to get it to a comfortable height.

I made sheetmetal blockoff plates for the cowl on the above mentioned Cougar, siliconed them in place. They really helped, but I'd use clips if you can, rather than silicone. Depending on how bad the cowl is, you could fix it from below. Pulling the dash on these cars isn't difficult. Welding overhead is no fun, but it's better than pulling the whole car apart for the cowl.
 
Heck of a nice looking parts car. I had the same dilemma with a 71 M-code Cougar. rotted to death, but I drove it for two years before it got totalled.

Undercarriage is just get in there and get dirty. I'd try some Simple Green and a pressure washer to knock the mess off, then suit up and a cup wire wheel on a 4.5" angle grinder. A couple coats of Rust Bullet and it'll be looking good. Build some wheel cribs to get it to a comfortable height.

I made sheetmetal blockoff plates for the cowl on the above mentioned Cougar, siliconed them in place. They really helped, but I'd use clips if you can, rather than silicone. Depending on how bad the cowl is, you could fix it from below. Pulling the dash on these cars isn't difficult. Welding overhead is no fun, but it's better than pulling the whole car apart for the cowl.
I have a 2 post lift. Shouldn't be too hard to get the car high enough and then I can roll around under it on a rolly chair. I do have a drawer full of angle grinders and wire wheels. I guess I way hoping you guys had some tricks that would avoid me sitting under the thing getting covered in rust dust and making a huge mess on the floor.

They should make some sort of attachment to connect a shop vac or dust extractor to suck up all the stuff you're knocking off the car. Otherwise it looks like I'm gonna come out looking like a coal miner.
 
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I could think of worse things than buying a Mustang as a parts car only to find it is in good enough condition to restore. That green is far from being "snot green," IMHO. And, it is one of my favorite shades of green on these old Mustangs. Being a factory A/C equipped Mustang is especially nice. I like those Holleys with vacuum secondaries. They let us use larger CFM carbs without causing any overcarbing issues at lower RPMs.

I have attached Volume 6 of the shop manual, which covers emission control systems and engine vacuum routing, to include two calibrations for the 35 4v engine versions that we left out of the original shop manual. That should provide you plenty of info to help you get the vacuum hose connections all hooked up again.

1973 was the year Exhaust Gas Recirculation first got installed on those older Mustangs. You also have a Dual Diaphragm Vacuum Modulator and quire possibly a Dual Diaphragm vacuum advance distributor. If you have any unusual vacuum routings, please feel free to let me know via reply in this thread.

If you need electrical schematics my Go To site is Forel Publications at:

https://www.forelpublishing.com/clickbank/index.html

Not meaning to be presumptuous, as you may be a very highly skilled Mustang restoration artist... But, we have a 1973 Mustang that was literally stored in a barn over 40 years. It has about 21,000 original miles on it, and other than some enhancements/upgrades we did it is in unmolested condition. If you need any photos showing how these were built back in the day, let me know and I can get photos of anything you need to see. We have a 2nd 73 Mustang, a deeply re$tored Mach 1, that is not in such original condition. But it photographs well.

For vintage A/C systems I like Original Air Group, a division of Classic Air:

https://www.originalair.com/
 

Attachments

  • 10010wm - 1973 Ford Car Shop Manual copy_PasswordRemoved_Volume6of6.pdf
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I could think of worse things than buying a Mustang as a parts car only to find it is in good enough condition to restore. That green is far from being "snot green," IMHO. And, it is one of my favorite shades of green on these old Mustangs. Being a factory A/C equipped Mustang is especially nice. I like those Holleys with vacuum secondaries. They let us use larger CFM carbs without causing any overcarbing issues at lower RPMs.

I have attached Volume 6 of the shop manual, which covers emission control systems and engine vacuum routing, to include two calibrations for the 35 4v engine versions that we left out of the original shop manual. That should provide you plenty of info to help you get the vacuum hose connections all hooked up again.

1973 was the year Exhaust Gas Recirculation first got installed on those older Mustangs. You also have a Dual Diaphragm Vacuum Modulator and quire possibly a Dual Diaphragm vacuum advance distributor. If you have any unusual vacuum routings, please feel free to let me know via reply in this thread.
Yep. I like the lighter snot green. If I ever get around to painting this guy, its going back to that color on the exterior.

Thanks for the info. I think this car may be missing just enough of those EGR/smog/emissions related parts that it may not be worth the headache of trying to put everything back to the factory configuration. I think it would probably be easier to hook up a holley sniper system and let the computer worry about the timing and emissions. :D

I did get the car up on my lift tonight to assess the situation. It turns out I will probably need to do both floor pans. I found a spot in the driver's side I had missed before I bought the thing.
Front seal on the rear end is leaking. I guess that's my excuse to swap in a 3.25 rear with traction lock.
Transmission is dripping from a couple different places.
Steer gear is leaking around the shaft.

And it was raining today and I took the opportunity to drive the thing around in the rain and watch for leaks inside.
The rear window and one of the quarter windows are both allowing water in.

Here's some of the pictures showing the sort of surface rust I'm up against. Its pretty much everything. Every part under the car I'm not going to replace will need wire brushed. Every rubber bushing also looks like it needs to be replaced.

I did have questions about replacing the floors. I see the floor is welded to the end of the front frame rail.
What sort of considerations should be taken around that?
Does the car need to be sitting with its weight on the wheels when the floor is cut and and the new one welded in?
Does anything need to be braced when the floor is removed to keep the car from shifting before the new one can be welded in?
Do new floor pans come with the bracket for the emergency brake? Mine has the little hook stuck to the underside of the floor.

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Hard to tell from pictures, but the frame appears to be solid, so you have a good base to build on. I sprayed the inside of my frame rails and cross members with Eastwood rust converter. Be sure to wear safety glasses as this is just one more very messy job.
 
Heck of a nice looking parts car. I had the same dilemma with a 71 M-code Cougar. rotted to death, but I drove it for two years before it got totalled.

Undercarriage is just get in there and get dirty. I'd try some Simple Green and a pressure washer to knock the mess off, then suit up and a cup wire wheel on a 4.5" angle grinder. A couple coats of Rust Bullet and it'll be looking good. Build some wheel cribs to get it to a comfortable height.

I made sheetmetal blockoff plates for the cowl on the above mentioned Cougar, siliconed them in place. They really helped, but I'd use clips if you can, rather than silicone. Depending on how bad the cowl is, you could fix it from below. Pulling the dash on these cars isn't difficult. Welding overhead is no fun, but it's better than pulling the whole car apart for the cowl.
I pulled the dash and blocked the cowl vents off. We welded a patch and fiberglass patched them in. I have an aftermarket AC so it deleted 1 already.
Jeff
 
Latest updates on this guy -

I think I can make out the vin on the engine block. It appears to be numbers matching. The passenger head still has the yellow writing on it. So I'm thinking its the original engine and has never been rebuilt.

I have ordered a set of 17x7 wheels. After a bit of researching around, I found the tire size 215/50r17, which is very close to the factory E70X14 size, and is available stupid cheap. Like $58 for the cheap tires. So I will be able to get some and do burnouts to wasted them and not feel bat at all. :D Hopefully will get wheels in later this week.

I managed to order 2 forest green racing mirrors off ebay. I will need to figure out how they are supposed to attach to the doors. I see scott drake makes some kit with oversized plastic grommets. Or I could do nutserts.

My deluxe avocado door panels came in. I am working on getting all the other bits in to be able to swap to those.

Like my other thread said, I'm pretty sure my rear end is shot. The car shakes once you hit 40 and it feels pretty sketchy. Even pushing it into neutral as it rolls does not stop the shaking. I am taking steps to score a 3.25 limited slip 3rd member. Then I will swap that in and do the rear bearings and seals at the same time. If I can figure out exactly which universal joints to get, I will go ahead and do those, too.

I knew I had an exhaust leak. I did not realize how bad it was. The exhaust from the headers back is swiss cheese. So there is a full exhaust in my near future.

We got some rain this week and I had a chance to drive around in it to look for leaks. There's a drip coming in around the quarter glass on one side, and another drip running down the inside of the back windshield.

And then I started trying to tackle the under side of the car. I already had an air compressor and some angle grinders, so I figured to try and use what I had. The paint/rust stripper discs work really well on some parts. I'm switching between an air die grinder and a corded angle grinder. The rear axle got about as good as its gonna get without disassembling things after about 40 minutes. My air compressor will do 200psi, but doesn't have the capacity to run the die grinder nonstop, let alone a sand blaster. I think the sand blaster is what it would take to really get this to the next level of clean. I tried the grinders with the discs on the bottom of the floors and they only do well where there's no undercoating. When they get on the thicker stuff, they dont even touch it.

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My order came in from eastwood. I got the gallon of their rust encapsulator plus paint and a bunch of $0.50 paintbrushes from harbor freight. The plan is to slowly sand down some of the rust under the car, then paint that section black. Rather than making it into a huge project to strip the whole thing and then paint the whole thing.

I ordered some mufflers, too. On my '69, a previous owner had installed a 3" exhaust with the summit 2 chamber guys. That car sounds great. I'm gonna see if I can make this one sound close to that.

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I'm also still trying to get this engine running a little better. It has a bit of a stumble idling at a red light (in gear, not moving) and while coasting at part throttle. I did notice the guts in the distributor are free to move around a bit. The distributor body is still seized to the block at close to 20 degrees initial timing. I soaked it with penetrating oil several times and whacked it with a hammer and a crow bar. The crow bar gouged into the distributor body pretty good, but still didn't turn it. My next attempt will be a CV axle puller on a slide hammer. CV puller is on order. Hopefully I can get this thing loose without snapping it off in the block and turning this into a bigger thing than it currently is.

Does anybody have any opinions about the loose stuff in the distributor? Or does anything else look amiss?

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Today is exhaust day. I went with the summit racing 2 chamber mufflers. Full 3" stainless all the way from the headers out the back.

I was playing around with my doodoo distributor and trying to set the points gap. I think its a lost cause. Due to all the play in it, when you set the gap, there's like 0.020" variation as the distributor guts wiggle back and forth. There's a very small window to set it where the engine will still run no matter how those parts wiggle. But the engine is definitely not running great. I'm still waiting for the CV puller to try and get the distributor body unstuck. Assuming that works, the plan is a new distributor, plugs, and wires. And hopefully that gets the engine running smoother.

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So today was a bit of an adventure. I started out by swapping over from the single chrome mirror to my dual painted racing mirrors.

I based my positioning off the existing front screw hole and the hole for the adjuster. I used the centerline of both existing holes as a guide for the centerline of the new hole. And with the front of the racing mirror attached to the existing front hole, that was enough to pinpoint the location for the new rear hole. Center punch, drill, debur, rivet nut, and the mirror can be installed. Then I got some measurements from some reference points and moved over to the passenger side. These are mirrors I got off ebay already painted. They are pretty close to the color of the car. close enough, they'll do until I get around to painting everything.


And right about then is when the real fun began. Fedex man arrived with my CV axle puller, so it was time to put up or shut up. I removed the distributor hold down clamp and slid the CV puller under the distributor. Then about 10 whacks with the slide hammer, and the stupid thing broke. I snapped the top of the housing. The shaft of the housing was still seized up in the engine hard. I sat there and beat the snot out of it from every direction for half an hour and it didn't budge. I've been soaking it in penetrating oil for the last week. Today I put some more and let it sit. And it just sat there. Nothing sank into the crack.

So finally I decided to pull out the big guns. I have a length of the biggest and strongest chain they sell at the store. I fired up the welder and stuck a link of the chain to the shaft coming up out of the distributor. Then I pulled in the engine hoist and lifted up on it. It was picking the front of the car up. The bumper was raised 5 inches higher than it normally is. Just about got the tires off the ground. Then I used a little sledge hammer and a crow bar to smack the hell out of the distributor. After about 20 whacks, the shock was enough to break it free and it dropped the car back to the ground. :D

The new distributor installed without any drama. The valve cover says it wants 8 degrees advanced for initial timing. I did about 10. Then dialed in the mixture screws using a vacuum gauge, and set the idle to around 600 while its in gear. It runs a lot smoother now. No more stumbling at idle or at part throttle. It still doesn't spin the tires when you stop on it. It does take off pretty quick. My other 73 is a 351w+C4 with the same 2.75:1 open rear end and it will at least spin 1 tire. Maybe this C6 has a different gear ratio for first gear or something?


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For today, I did the plugs and wires and swapped some of the interior out. All the old plugs looked pretty new on the part that stuck out of the engine. But from the threads to the tip, 7 of the 8 of them were black and covered in still liquidy oil. They were all gapped around 0.040", which is pretty much where they come out of the box. I read 0.032-0.036 for the gap, so thats what I set all the new ones. I'm thinking with this much oil in every cylinder, this engine isn't far off from getting yanked out and rebuilt. :(

Back in the inside, I pulled off the plain door panels. While they were off, I cleaned up the window guide rod with some sandpaper and brake cleaner. Then greased it up so the window will roll down smoothly. I swapped a couple little parts around, and then was able to install the deluxe door panels. I still need to sort out the little ring and grommet for the mirror adjuster on the driver's side. And I'll come up with something to cover the holes for the door speakers that I dont have in my car. I also swapped out the dash end caps from black to green, for that little extra smack on the face of the 70s as you open the doors.


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