67
stang,
Another thing the '67 and later Mustangs had, was reinforced shock towers to handle the torque of the big block engine.
It's not just a matter of dropping it in. I like small blocks better, because of less weight and there is more room to work on/around them.
You can get a lot of HP out of a small block, but you want to make sure your car can handle it.
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1967 Mustang Convertible - 289-4V with a C4 Automatic.
1992 Bronco - 302 EFI Automatic
"When they call the roll in the Senate, the Senators do not know whether to answer "Present!" or "Not Guilty!" Theodore Roosevelt