you guys need to research your facts better.
1- the car is a Dodge Challenger. It was available with a Hemi engine, amongst a handful of other engines (318, 340, 383, 440, and probably a slant 6). The car itself was never referred to as a hemi. It was always a Challenger, whether a Challenger R/T, T/A SE, etc... "Hemi" is short for hemispherical which is the shape of the inside of the combustion chamber- for which this style of engine was named after. The Challenger was made from 1970-1974. The chassis was referred to as an "E-body" (also for the Plmouth Barracuda and 'Cuda counterparts) a name they commonly are called.
2- Chrysler produced many versions of the family of "Hemi" engines over the years. they offered them in the 1950's with Chrysler, dodge and DeSoto versions, they offerd them in the 1960's through '71 as the 426 Hemiin both street and race versions, and now they have the Hemi again in multiple displacements. I don't know the hp ratings offhand, but you can learn a lot about this engine on the
www.allpar.com website.
check this link:
http://www.allpar.com/mopar/hemi/Hemicntr.html
3- camaros are not 2 of the rarest muscle cars you can get. they produced many thousands of them. In fact, the 1969 Camaro is being reproduced again today. you can buy a new "shell". all new sheetmetal, the works.
Of course, your statement is terribly general. by this I mean what do you consider rare. do you mean factory production cars? (something straight off the dealer lot) tuner cars? (yenko, baldwin motion, etc) Factory race cars? (hemi dart, thunderbolt, etc) or Factory one off mules? (one of a kind development test cars)
If you are referring to dealer lot cars I'd consider the 1971 Hemi 'Cuda convertibles amongst the rarest. They made like 8 of these cars. They're multi million dollar rides now if you are lucky enough to have one.
If you mean tuner cars, this could be any of a number. For exampe, in 1969 they built 2 ZL1 corvettes. I'd consider this much rarer than the 69- 1969 ZL1 camaros they made that year.
Factory race cars like the Tunderbolts or Hemi darts are incredibly rare.
By comparison, they made about 602 Z28 camaros in 1967, over 6,000 in 1968 and over 20,000 in 1969. The rarer Z28 camaros are the ones with the cross ram intakes. But, they are by no means at the top of the rare list.
Don't get me wrong, there are rare camaros out there. There is a '68 camaro that is 1 of 1, but I think it was a car built at GM for an executive never meant for public sale. I think it was a Z-28 convertible. Therefore it can't really be counted because it was never meant for production or public sale, even.