1/24 Revell Mustang GT350 H

[Neddy]

What better rear axle assembly could you find to tame a Mustang?  They use them almost exclusively for hot-rods for a reason.

[Six97s]

That's different, nice idea.   I was aware of the 1968 "Green Hornet" Shelby with IRS, but I didn't know it had been conceived much earlier.  I did some reading around this today. You probably already know that a '65 was built in this configuration recently - photo of the IRS here: 

 

https://www.motortrend.com/uploads/f/132719256.jpg?fit=around|875:492

 

Interesting (to me anyway) that neither uses a Ford axle, I guess because the Ford 9" has a stamped housing with a removable third member, so a Salisbury type diff is more suited to mounting to the chassis and hanging the suspension from it.

 

The original concept:

 

https://performance.ford.com/content/dam/fordracing/enthusiasts/newsroom/image/2016/03/THE INSIDE STORY OF HOW AN IRS MADE FOR MUSTANG WON LE MANS/IRS Drawing.jpg

[Anteater]

Thanks for those URLs. I'm creating some mounting plates to locate the axle control arms but I'm currently undecided whether to use the Jaguar radius arms or create link bars as shown in the motortrend photo. The Motobitz kit includes a nice pair of Jag arms so I'll probably use those, but Google tells me there have been various ways of controlling fore and aft movement when retrofitting to first gen Mustangs. Basically, I'm concluding that if it looks right, it is right. Also, working in 1/24th scale means the consequences to my personal safety are non-existent if I come up with something that's sub-optimal from an engineering perspective.  

[Six97s]

16 minutes ago, Anteater said:

f it looks right, it is right.

 

I rely on that principle more often than not.

[Anteater]

Right so, time for the last update for this week. 

 

Building platforms for the rear axle carrier gave the necessary height but there's still the problem of centering the wheel in the arch. It wouldn't take much to make the whole thing look wonky, can't be having that. I've stuck a bit of rod either side to create a slot for the axle to locate to, all done by eye because that's how I'll view the finished car.

 

I've added a length of rod to the stepped section on the plates for the radius arms too, but that's most because it just looks better.   

 

 

 

Next step is to narrow the axle to bring the wheels within the bodywork. The easiest way was to saw the end off each hub and drill out a hole to receive a new stub axle. The kit wheels are snap fit but that won't work now, so I'm filling and drilling the backs of the rear wheels to suit. 

 

 

 

The assembly mocked up:

 

 

 

I need to tweak the mounts to set it dead level but I'm fairly happy with it. Shame all this work will be essentially invisible when the car is set on its wheels! Thinking about it, it'll only be invisible if I get it right so it's worth taking the time. This is a multiple pint problem and can't be rushed. 

 

 

[Spiny]

As you say, the work will only be invisible if you get it right. Looks like a good bit of micro-mechanicking going on here and, thile the work may be invisible, the end result will certainly be worth it.

[Neddy]

I can only echo Spiny's comments.  It's a lovely bit of redesign, well thought through and equally well executed.  When finished it would be worth displaying on a mirror to show it off.

[Anteater]

Thanks. The mounts for the arms weren't quite right so I've added some fake bushes, otherwise the fake suspension wouldn't fake work. 

 

 

 

[Six97s]

Nice fake engineering. 

[Anteater]

Being a natural troublemaker, the usual order in which I build cars is rarely in line with the instructions. However, changing the back axle has led to this one getting all a bit chicken and egg. The last Mustang I built (OOB) didn't sit quite square and I had to shave the tyres to stop it tri-podding. That was my first build of modern times and I'd like to think my standards have improved in the intervening few years, so tripods are firmly off the menu this time! 

 

So what? Well, I normally wait until the engine and running gear is in place before I add the wheels and tyres, but there are too many variables here to take a chance on all four wheels being at the same altitude simultaneously. The wheels have to go on early.

 

First of all, the chrome gets stripped and the bare plastic primed. Bye-bye bling, I can actually see the detail now.  

 

 

The kit comes with two-piece wheels and you'll maybe recall I filled and drilled the backs of the rear wheels to fit the new stubs. Snug. 

 

 

 

And here's an idea of what the wheel assembly should look like.

 

 

 

I'll be sanding the bobbles off the tyres of course. An important step closer to getting the back axle located. 

 

[ElectricLightAndy]

That's looking fabulous 👌 

[Neddy]

Isn't it just!

[Redstaff]

Good progress on the mods  

 

Ian

[Anteater]

Measure twice, glue once. Pause, measure again, hold glue, measure again... ah close enough? GLUE GLUE GLUE!

 

 

 

 

It's either right or it isn't.

 

I have much superglue on my fingers. 

[Marco F.]

5 minutes ago, Anteater said:

Measure twice, glue once. Pause, measure again, hold glue, measure again... ah close enough? GLUE GLUE GLUE!

 

 

 

 

It's either right or it isn't.

 

I have much superglue on my fingers. 

 

5 minutes ago, Anteater said:

Measure twice, glue once. Pause, measure again, hold glue, measure again... ah close enough? GLUE GLUE GLUE!

 

 

 

 

It's either right or it isn't.

 

I have much superglue on my fingers. 

Great ideas,superb work, this is going to be an absolute masterpiece when finished. 

After all these years I guess I am still an absolute beginner 

Congratulations and I love your skills 

Marco F 

[Neddy]

That's a lovely sight, a Jag diff hanging from a Mustang.  Looks like it grew there!

[Anteater]

Thanks for the feedback and encouragement. 

 

In all of this evening's excitement I almost forgot to tell you what an utter pantomime the rear wheels turned out to be. As the Jag axle is a bit wider than the Mustang chassis I had already trimmed the hubs down. However, test fitting of the wheels showed it wasn't enough. The axle wasn't stuck in place at this point but it clearly needed to lose a bit more width. 

 

Evidence Photo #1 - AWFUL!

 

 

 

Thing is, I couldn't trim the IRS assembly any further. The answer would have to come from changing the offset of the wheels. 

 

This was the problem - the two piece wheels have an inner face for push fitting to the kit axle. That bit, the part I had diligently drilled and filled in an earlier installment, was simply too big. It stood too proud. No getting away from it, another re-think was required. 

 

 

My solution was to drill the centres out and enlarge the hole with a knife until it cleared the axle hub. Not so neat, but effective.

 

This created the next problem - nothing remaining for the stub axle to insert into. I needed to make sockets and glue them to the inside of the wheel-outer. A scrabble in my drawer of tubing yielded the right stuff, but a short length with only millimeters to spare.  

 

 

 

Better offset, and now glued in place.

 

 

 

YO STANCE

 

 

 

More next week. 

[Pete in Lincs]

Nice save. And now, lie down and breath slowly and deeply. There there....

[Neddy]

Ingenious, well executed too.  1:1 scale Cobra replica builders had the same problem using the Jag diff/rear axle assembly, it was just too damn' wide.  The normal (and crude) solution was to widen the wheelarches but they just didn't look right.

[Vesa Jussila]

3 hours ago, Neddy said:

1:1 scale Cobra replica builders had the same problem using the Jag diff/rear axle assembly,

 

Maybe this will be Mustang replica 1/24 with Ford V-6 from Capri. 🤣

[Windy37]

Some good engineering happening here . I've just been watching the Car SOS TV show rebuild a completely rotten '65 Mustang . Some good detail footage of the engine and chassis , although maybe too late to help you out . Worth a watch though . 

Gary 

[Anteater]

I saw that episode of Car SOS last week, there seemed to be very little left to weld to! The specialist they outsourced to seemed to know what they were doing but the risk remains that a car like that becomes a patchwork quilt of welds and new sections. You'd want to have confidence it had been done right.

 

Along with the mammoth job on the shell, I assume the retention of the original live axle at the rear was necessary to make up the points to retain it's identify under DVLA rules. The front crossmember was bespoke, the front suspension completely changed to double wishbone IIRC and the larger capacity engine was new, not sure about the transmission. What do we reckon the total bill was? Must be at least £50k of labour into the body before paint or any mechanicals. What with a colour change and conversion to RHD it didn't bear much relation to the car they started with but the owner looked happy enough, as you might well be...

 

[Anteater]

7 hours ago, Vesa Jussila said:

 

Maybe this will be Mustang replica 1/24 with Ford V-6 from Capri. 🤣

 

Arguably an improvement!

[Anteater]

@Vesa Jussila

 

I joke of course. But I recalled they did use the Ford Cologne 2.8 V6 in the Mustang II. You'll know the European version of the engine produced 160bhp in the Capri. I looked at the figures for the Mustang II with the same engine in an American state of tune and it's not good news... a whole 105bhp which dropped to a miserable 97bhp after catalytic converters.  ☹️

 

Maybe stick with the 306bhp from the Shelby 289 after all.  

[Spiny]

Unfortunately that's fairly typical for US engines of that age - my old '78 Pontiac was even worse. Even though it had an extra 15hp courtesy of having the 4-barrel carb, it still only achieved 150bhp from a 4.9l V8. To compare to modern cars, my one-litre fiesta produces over 80% of the horsepower from 20% of the capacity.