Tex's RETRO 1973 Ford XA Hardtop Build (Aussie Falcon)

[Tex Scrotum rides again]

G'day, I'm new to this forum and I have been reading through a few of the great build threads on here, so I thought I'd share my build.
The car in question is a 1973 XA Ford Falcon Hardtop (Coupe), made in Australia.
The pic was taken about 12 years ago before I decided to take it off the road for a few rust repairs.
As is common, the "few" rust repairs turned into a full strip down and rotisserie restoration.
But as even more common, there the car sat on the rotisserie while I got a game plan together and let my young family grow up a bit so I'd have time to dedicate to my car.
About 8 years passed before I made a proper start a year ago.

BUT first before I go further, let me post this up and see if it all works for me.
Plenty more to come, I promise!

[Tex Scrotum rides again]

Ok, I seem to have mastered posting on this forum.

First a little about me, I'm 52 and have NO formal qualifications in anything to do with car building, having said that, I have been playing with cars most of my life and I'm pretty handy with tools and prepared to learn and have a go!

Secondly, a little about the car because although a few of you may be aware of this particular Australian model, a lot of you may be scratching your heads.
Most of you would be aware of MAD MAX, well Max's car was based on the model after mine, the XB Hardtop. The differences between XA and XB is basically the front sheet metal and tail lights.

My XA started life as a lowly 6 cylinder auto Fairmont painted in Copper Metallic colour Vinyl roof with White interior, so nothing special which means I can pretty much do what I like with it, without upsetting the "purists".
My car looked similar to the car below when it left the factory in 1973....



Not to everyone's taste including mine.

I bought the car about 15 years ago before the "Muscle Car Boom" and it was painted a lime green colour, was fitted with a 351 Cleveland and C4 auto with a 9 inch rearend.
I rebuilt a Toploader gearbox and fitted a Detroit Locker with 3.9 gears and 31 spline axles.
I changed the cam and ported the 2V heads and added a single plane manifold but left the 780 square bore Holley and with these mods it performed pretty good until I took her off the road.

Next post I'll go into more about what I'm going to do with the old girl.

Cheers!

[Godbolt]

Yes please!

[Tex Scrotum rides again]

What to do, what to do???

My main influences were Group C racing which was a bit similar to your TransAm racing in the states.
Group C was a "touring" car race category which was very popular in Australia during the 1970s thru to the early 80s and included the annual BATHURST 1000 km (600 mile) endurance race which is a really BIG deal here in Oz.
The XA GT Hardtop won this race twice in 1973-74, see pics below....





My father took my grandfather and I up to Bathurst for the 1974 race (I was only 10 years old) and although I was only young, it was that race which made fall in love with the XA Hardtop.

So those along with other memories being my influences, my car was always going to be "race" inspired.

Without boring you all to much and going back in history to much, what was happening in Australia was similar to you guys in the states with NASCAR and TransAm, the factories were at each other's throats trying to build faster and faster street cars so they could "win on Sunday....sell on Monday".

Hence we also had a lot of "factory" specials and under the counter performance options available to people in the know which spawned all sorts of myths and legends exactly like what had happened in the U.S. a few years earlier.

It was these factory specials and reading about other factory specials being built all over the world during this era that captured my imagination and interest.

Kar Kraft, Holman and Moody along with others were also part of my influences.

I always liked the no-nonsense and stealthy ways the factories and those supported by the factories skirted the rule book in order to get any advantage.

Below is a car that was also a huge influence on me and one that you guys maybe more familiar with....Allan Moffat's KarKraft built Boss 302 Mustang...



This car was a giant killer here in Australia in another category which ran in tandem with Group C but they were allowed a lot more freedom for modifications.

Sorry to go into so much depth but due to it being a foreign car and also it will hopefully make a little more sense of what I'm trying to attempt.

More to follow.

[Tex Scrotum rides again]

So what if?

What if Australia didn't have the "Supercar Scare" which changed EVERYTHING as far as Muscle cars were concerned in Australia....



The above headlines put pressure on the Australian government who in turn put pressure on the manufacturers to STOP the arms race that was occurring with factory muscle cars.
The Australian government threatened to stop buying cars made by the big 3 (Ford, GM and Chrysler-Mopar) if they didn't stop creating "Supercars".

Obviously the factories shat themselves at the thought of losing valuable government contracts and they caved in, suspending all "race specials"

All Aussie Muscle car enthusiasts are familiar with this story!

But what if it never happened?

Now I know "what ifs" are all open to all sorts of criticisms etc but humour me as its my what if and I like to play.
Although the factory specials continued but at a much more subdued and secretive pace, it makes me wonder what would be if political correctness hadn't got in the way of a good old factory oneupmanship battle where money was no object to winning races.

So my Hardtop will be built in that sort of spirit using parts, technology and materials that were readily available during that era.....hence the RETRO tag on my heading.

Yes it will be all fantasy and people will be able too pick lots of holes in what I'm attempting and I'm sure a lot of it will be controversial to what could and couldn't be done back in the day, but hey.....it's my fantasy and it'll keep me and maybe you amused for the next few years.

Anyway I've waffled on way to much so next post I'll outline my plans....

[Tex Scrotum rides again]

Thanks for sticking with me so far!

Now I'm no millionaire and I'll be doing 99% of the work myself but on the plus side, because I'm sticking with 40 year old technology things shouldn't get to outta hand.

The PLAN; the car has to be road registered, be fun to drive and maybe do the odd track day.

BODY; the underbodies of these cars are very similar in construction to the 68-70 Mustangs and besides the obvious, knocking the body into shape, the three main focuses will be weight, rigidity and aerodynamics.
Weight loss and increasing stiffness is going to be hard to achieve but if there's less weight then there's less strength required to control that weight.
Stiffness will be increased by working with the shell and the way it was constructed as much as possible.
Because the shell is a monocoque construction, then I will try and stick with that form of construction as much as possible and will try and limit the use of steel tube, plus it's usually lighter.
Because I'm also trying to build a factory type road race car, there will be no rollcage, down here in Oz we don't have anywhere near the freedoms you guys in the states have when it comes to rego laws.
Because of these restrictions all mods will have to look factory'ish which suits me.
Improvements will be made to aerodynamics where practical and will be reasonably subtle.

ENGINE; with the help and expense of an engineer we can put Big Blocks in these cars but Big Blocks are not light.
These cars came out with 302 and 351 Clevelands which are pretty heavy.
As I only want between 430-500hp and the car will be relatively light I'm going to use a smaller Small block.
I've always been fascinated by the BOSS 302 engine probably because it's a hybrid engine.
The light weight of a Windsor and the breathing of a Cleveland.
The other thing I like about the Boss302 is that it fits into my era very well and could theoretically have been used by Ford Australia as we were always a few years behind the U.S. In terms of car styling and mechanical updates.
If finances allow (and they should) I will get even more exotic and use an Aluminium block and SCM Aluminium 4V replica heads.
Induction will be Quad Weber carburettors.



GEARBOX; will be at the moment a close ratio Toploader with possibly David Kee Aluminium cases.

REAR AXLE; will be 9 inch with Aluminium centre, possibly full floater. However I'm looking at lighter options.

SUSPENSION; will be up rated factory with tweaks here and there.

BRAKES; Disc all round and period 4 piston calipers up front.

WHEELS; 3 piece Aluminium 15 X 12.5 rear and 15 X 9.5 front.



INTERIOR; will be bare bones with essentials only.

COLOUR; will be BLACK on BLACK.....the Mad Max influence coming thru there.



At the moment I'm laid up with a hand injury which gives me plenty of time to bring this thread up to date with where I'm at, remembering I've been working on the car for the past year, mostly doing rust repairs which I won't bore you with too much.

Cheers!

[Mr.VENGEANCE]

OH man I love those XBs.. that is gonna be such a cool ride!

[Tex Scrotum rides again]

Yes please!

I've been following your build Godbolt which is excellent, good to see another Aussie here.

Cheers!

[Tex Scrotum rides again]

OH man I love those XBs.. that is gonna be such a cool ride!

Thanks mate, remember mine is an XA but much the same, hope you enjoy, I will be bringing this thread up to date over the next few days with a lot of pics and posts and then obviously the build will slow down to a more normal pace but first I have to get my wounded hand healed (bloody angle grinders).
But if it weren't for the injury, I doubt I would have had time to do this thread properly, I'm just bored outta my mind at the moment.

Cheers!

[Tex Scrotum rides again]

The car was stripped of every nut bolt and screw and put up on a rotisserie where it sat for a couple of years.
I guess there's a few reasons why I didn't make a start, one because I didn't think I had the time to commit to it, and two because I wasn't entirely sure of how or what I was going to do with it.

But I would spend plenty of time going into the garage with a beer and just staring at the car, studying it's shell and trying to formulate a plan.













Like I mentioned before, these cars had similar architecture to the 69-70 Mustangs and some of the suspension along with engines, gearboxes etc are shared with the Mustang.

However you may notice that there is a few extra braces here and there that these cars needed because of the terrible Aussie roads back in the 1970s.....actually some would say the roads are still quite bad!

Next post we'll check out the rust that these Hardtops are famous for!

Cheers!

[Tex Scrotum rides again]

As I said before, these cars are very prone to rust and as this car was my daily driver before it was retired to the garage, the rust was accelerated because the car was parked right next to the ocean at work and was continually covered in coke dust from the steel works.

Also the car had had previous rust repairs done which were of a very poor quality, mostly bogged and filled or very poorly welded in plating.

Dodgy plenum (cowl) repairs....



A & B pillars pretty messy....





The firewall seam that joins the plenum to the firewall in the engine bay needed attention....




B pillar latch areas were a mess....



Both sills were shot....



Upper A pillar hinge area also stuffed....



Along with a few other areas like the roof gutters and rear tail light panel needing repairs as well.

There's also some rust in those huge rear quarter panels and on it goes.

Now being a fairly low production run compared to American cars (there was only about 5000 of these made over about 6 years and three different models XA XB XC) that after market panel replacements are just about non-existent.
There are some smaller repair panel sections available and quality of fit varies from reasonable to bloody terrible from what I've read.
I look at what you guys in the states have available for restoring old muscle cars and get rather envious.
But where there's a will there's a way, and if a man built it then a man can repair it!

Next up I'll start going over briefly about some of the rust repairs.

Cheers!

[Tex Scrotum rides again]

So armed with a little cheap Gasless Mig welder and really no idea of how to weld, I started on the rust repairs.

First up I decided to attack the upper A pillars (around the windsceen) which had been previously repaired by other owners.

Attachment 127145

Attachment 127146

Attachment 127147

I slid angle down inside the pillars so the joins were overlapping for strength....

Attachment 127148

Where the pillars join the roof also needed attention...

Attachment 127149

Attachment 127150

With the RH side done, I moved on to the LH side which was worse...

Attachment 127151

[Tex Scrotum rides again]

Next was the B pillar door latch area...











Plenty of measurements were taken to ensure that the latch was put back in the proper position.
With the LH side done, I then moved on to the RH side which was just a repeat of the LH side.

Cheers!

[Tex Scrotum rides again]

Next up was the Plenum or Windsceen Cowl.

This was a big job and these cars are well known for rust in this area, and mine was no different living up to expectations.
There's quite a few braces that have to be removed to access the plenum and this whole area is structural so extra bracing was added where needed.
RH side...

LH side...

Top of plenum removed after drilling out eleventy billion spot welds...


And after a fair bit of welding and fabricating...


The seam that runs across the firewall was also cactus...

There actually 3 seams that all join here, upper plenum, lower plenum and the firewall...


The upper plenum lid also needed quite a lot of work as well and it took a fair bit of time replacing all of the seams as the work is quite fiddlely.

Cheers!

[Tex Scrotum rides again]

At the same time I was doing the plenum I also repaired the upper A pillar door latch areas...





That was the LH side and the RH side was also repaired in the same manner.

Finally with a good base to work off, it was time to nut out a few stiffening modifications.




Cheers!

[Godbolt]

Nice work on the rust repairs! It was in much worse shape than I was expecting from the original photos but good job. I like your plan and love the quad webbers.

[Tex Scrotum rides again]

Nice work on the rust repairs! It was in much worse shape than I was expecting from the original photos but good job. I like your plan and love the quad webbers.

Thanks mate, you weren't the only one that was surprised about the condition.

Rust is like an iceberg, what you see is just the tip.

But starting with a good solid foundation is pretty important and with the values of these cars getting a bit crazy it makes it worthwhile to do it properly and once it's done I can sit back knowing the body is in good shape.

It's always been a dream of mine too run a Webered V8 and when the opportunity came up to buy this setup, I jumped at it.
The manifold is a Shelby Boss 302 with early 1970s made in Italy Webers that are in very good condition.
So reasonably period correct for my car and the same setup as Allan Moffat's Boss 302 Mustang.

It may seem a stretch that Ford would consider running Quad Webers but when you consider that Chysler ran triple Webers on their Hemi 6 at around the same time then maybe not so much of a stretch, I have a pretty imaginative mind sometimes lol.

Ideally I would've loved to get my hands on a set of Autolite carbs below....



But a little out of my price range.... I think the guy was asking about $7500 Aus for these.

Cheers!

[Tex Scrotum rides again]

So now that the plenum was ready to put back together I was ready to explore ways of stiffening up the firewall as I planned to use a strut brace.
A later model XC Hardtop had used a simple strut brace,( known as option 97 which was part of a Homologation package designed for Bathurst , very few were actually made) which attached to the firewall seam as did various Mustangs.

I actually bought some repo Mustang strut braces cheap to play around with....



The Mustang braces will need modifying to fit, but I'm after a "factory look", I'm not into "bling" but I may try to replicate the look of these steel braces out of Aluminium later on down the road.

But it would be little point installing a strut brace if those loads and flex were transferred into the firewall.

I looked at various ways of strengthening the plenum firewall area using tube etc but one, I didn't want to start running steel tube throughout the car and two, the weight would start adding up!

I noticed that the factory had installed a rib on the inside of the plenum....



Then whilst doing some research I found that the factory had installed another rib further along on a later model XC, so maybe the factory new something.

I started researching monocoque construction of race cars, aircraft and even boats and came up with a plan.
I would fabricate 4 more ribs and turn the plenum into a proper "beam" giving the firewall a lot more stiffness.
This would also be significantly lighter than reinforcing with steel tube.

Cheers!

[Tex Scrotum rides again]

Here's a cross sectional diagram trying to explain the forces as I saw them...


So after lots and lots of measuring I made some ribs to install inside the plenum, keeping in mind that the windsceen wiper mechanism was also inside the plenum and had to be free to do its thing...



Some odd shapes there but so is the inside of the plenum....




A mock up with the Mustang braces....


It maybe controversial and it sure was a hell of a lot of work but I think the theory is sound, besides I ran it past my father who's an engineer, he thought I was mad because of the amount of work but liked the idea and gave his approval.

Cheers!

[Tex Scrotum rides again]

With the reinforcement taken care of it was time for some paint....




And with the upper plenum ready to pop back on...



But before I plug weld the top back on FOREVER, I made a little stainless steel plaque too commemorate the occasion...



A bit weird I know but that plenum dam near sucked the life outta me and I was glad to get it back together!



Cheers!