Strongest series Mustang II? Boss?

Hello,
Unfortunately, the most powerful Mustang II—even the Cobra—only had 140 hp.
I once heard about a prototype "Boss" model being built; are there any documents regarding that?
I want to get my V8 approved by the TÜV in Germany, but they can't certify anything over 190 hp; I need to prove that such a version actually existed.
 
I'm not 100% certain about any production II having anything exceeding that 140 hp number. There may have been some specialty cars somewhere, but I believe they're pretty rare if they exist. I don't even think that the few Monroe Handler replicas had anything other than the stock 302 offered in other trims.
 
Hey, i checked the Mustang Red book. Nothing exceds 140 HP.
The 4 Speed Manual was available beginning 1976 model. It ist in the Text in the second Page. First Page Shows Option "4-speed Manual..."
Good luck For finding the right TÜV Inspektor.
 

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know whether the chassis can withstand the increased horsepower or if it might fail.
We are allowed a 20% increase in power, but anything beyond 40% requires us to provide supporting evidence.
The Mustang II was available with 141 hp, so I am not allowed to drive one with 200 hp without a structural integrity certificate.
However, if there were a model with over 200 hp that had already been road-legal, you would be allowed to drive that.
 
I am pretty sure there have been many folks in North America that have had well over 200hp with no structural upgrades. Would a documented car like that be useful for your purpose?

Any Mustang II owner that put a stock 302 EFI out of a foxbody in their car would easily exceed those power numbers. I would bet there have been MANY of those folks over the years.
 
I am pretty sure there have been many folks in North America that have had well over 200hp with no structural upgrades. Would a documented car like that be useful for your purpose?

Any Mustang II owner that put a stock 302 EFI out of a foxbody in their car would easily exceed those power numbers. I would bet there have been MANY of those folks over the years.
Yes, there were some Mustang IIs with over 200 hp—even 300, and I even found one with 400 hp—but our TÜV inspectors want to see proof that such a car was built as a production model, even if it was only a limited run.
I could also try to get confirmation from Ford. If they were to issue a document stating that the Mustang II body can handle 200 hp, I would be able to get it officially registered.
But Ford in America would never do that—especially since there is no point in making such inquiries for cars of that age.
 
I don't think such a car exists. Remember horsepower for everything was dropping (especially "official numbers" for insurance reasons) for fuel economy.

Maybe they would take something like this...

dynodon.webp
I don't what numbers they were making for horsepower, but it was called Pro Stock.
 
I don't know how much this helps you, but the Mexican version of the Mustang II used a 302 V-8 rated at 205 horsepower. 20 percent over that would get you to 246 HP.

 
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I clicked the link and found literature, but none of it was Mexico only, it all appeared to be standard Ford USA. Maybe you can find some contact info and reach out, maybe they can help?
 
I had the same experience; I managed to find brochures listing 205 hp, but unfortunately, I haven't found a data sheet or vehicle document yet.
I’m finding bits and pieces little by little. ;-)
If anyone here has the Mexico registration details for their Mustang II, I would really appreciate a picture of the vehicle document.