what gear ratio came with a 1964 impala ss

The '64 Impala SS was available with a bunch of different engines, smooth: 283 V8 170 bhp. 283 V8 195 bhp. (L30) 327 V8 250 bhp @ 4400 rpm, 350 lb-ft @ 2800 rpm. (L74) 327 V8 300 bhp @ 5000 rpm, 360 lb-ft @ 3200 rpm. (L33) 409 V8 340 bhp @ 5000 rpm, 430 lb-ft @ 3200 rpm. (L31) 409 V8 400 bhp @ 5800 rpm, 425 lb-ft@ 3600 rpm. (L80) 409 (2x4 bbl) V8 425 bhp @ 6000 rpm, 425 lb-ft @ 4200 rpm. Do you know which one the car you're asking about has?

Generally in that model year, the stock gear ratio with automatic transmission was 3.36:1, and I believe that this ratio also applied to the 3-speed manual. The more common 4-speed gearing used with the high-performance 409 was the well-known 4.11:1.

Mine had 6cyl 3 speed on the column

My speedo is 20 miles per.hr. slower than I'm really driving, rear end and tranny both look original .

@1964impala. if your Impala has the shifter on the column it is not an SS. SS had shifter on the floor / bucket seats. Regular Impala had full bench front seat.