[ QUOTE ]
The Mach I came with the 351 Windsor in 1969. It had a 2bbl. standard, 4bbl. optional. From there, there was the 390 and the 428 Cobra Jet.
In 1970, the 4bbl. engine was of the Cleveland variant, which was a new engine despite sharing the 351 size. These engines are much better, apples to apples. However, most people in the hobby prefer the '69.
[/ QUOTE ]
For some reason I thought the 351 Cleveland was available in the '69 Mach 1.
If you want to just get in and DRIVE the car with (or without) the wife n' kids, go for the Z! It sounds like a gas n' go deal and you can't go wrong with the investment... or styling.
But if the Mach I does have a 351 C, then I would think of investment potential. I heard the Clevelands are scarce.
Again, 442w30 is probably right, and the engine wasn't available in 1969.
All-in-all, being a Ponchohead, I'd vote for the 'Bird if'n it was me!
~Goat72