The famous Grand Turismo Omologata (GTO) was for the first year offered to the public. Available only in 1964 as an option on the 1964 Pontiac Tempest LeMans. GTO optioned Tempest Lemans featured distinctive appearance items in place of standard LeMans features. Standard Engine was a 389 cubic inch with 10.75:1 compression ratio which produced 325 horsepower at 4600 rpm’s. Optional you could factory order the same 389 cubic inch motor which produced 348 horsepower at 4600 rpm’s.
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The only engine available on the’64 GTO was the 421 CI V8 with three 2 BBL carbs.
The 389 was only available in the regular Tempest.
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