I have an 1984 Monte Carlo SS with a 350 trans and 373 gears and 2400 converter... I am doing 55 mph on the highway and I am at 3000 rpm.... My question is what will the difference be if i switch to 355 or 342 gears on highway? Will either of these put me at 70 mph highway??

 

Heres a chart that should help you deceide!

Speed versus RPM calculator

Hope this helps!

 

thanks the chart helped.

 

Yw!

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