65 Impala 409 4 speed overhaul - input requested.

ngale65

Member
Have a 65 impala, factory 409 340hp with an automatic. Original paint unrestored car. Plan is as follows. Currently putting together a 409 bored 60 over with a stroker crank. should push 550hp on pump gas with no issues. Planning to put a wide ratio 4 speed in the car. Question is what ratio rear end gear to run. I don't care about racing the car. highway is important as we drive the car, not into trailer queens. I'm thinking a 3.42 but open to advice. Last car I built was way to radical for the street with a 3.73 and a 496 big block with a 4 speed. IMG_1877.JPG
 

63impalass409

Well Known Member
Supporting Member 2
Love your car!! In my 65 409 4speed with a m20 wide ratio I run a factory 3.07 12 bolt posi and love to cruise around, not the fastest but enjoyable to drive on the street and freeway.
 

i8ntnuts

New Member
Very nice. I do think you woukd enjoy something like a 370 rear gear if you don’t drive on the freeway,or very little freeway driving. This is just a thought,and if you have a short tire maybe the tall gears are perfect for you.
 

DonSSDD

Well Known Member
Supporting Member 2
3.08 or 3.36 stock would be good if regularly driving over say 55 MPH to keep RPM's lower. You can switch from a taller tire on the highway to shorter on the street if you want to play with it. How tall a tire?

Cool car.
 
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