Rear gear question

[Barry Stewart]

Hey guys I have a 440-6 with a torqueflite . I have a Dana with 3:54s. Looking for better launches but don’t want to go to radical. I enjoy cruising at 65-70 too. Will I notice much difference with 3:73? Is it worth the swap? Or should I wait till I can afford an overdrive and go 4:10?

 

[704406]

I swapped my 70 Cuda 440-6 torqueflite from 4:10 to 3:54 years ago, it made roughly 700-800 RPM difference at cruising speed.
I don't think the benefit, verses the cost, to swap to 3:73 will be worth it, as the dana 60 is quite involved to do gear swaps. Maybe wait for the 4:10, overdrive swap you mentioned. That's the best of both worlds.
Cruising at 70 with 3:54s and 15" tires RPM is 3600-3800 not real comfy for long cruising and fuel milage, at that engine speed it also creates enough vacuum to pull on the secondary carbs with very light throttle applications.
Just my opinion

 

[moparleo]

Let your torque convertor work for you.