I'll try to keep it short; for example, I drive at 70mph in my '84 TA, tach says about 2,400 rpm. If I drive at 70mph in my '91 bird, the tach says only about 1,800. Is it rear gearing that determines this, or something with the tranny? Maybe both? I'm (almost)clueless when it comes to this stuff.

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DR Stevens
1984 Trans Am 305HO L69
sucks gas, hauls ***
1991 Firebird 305 LO3
for days when I need a/c

 

Its in the rearend. The internals between the two transmissions are almost identical (as far as gearing anyway). It almost sounds like the '91 may have 2.73s and the '84 probably has 3.42 or 3.73.

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