3.55 vs 3.23 - 1972 440/4spd RR

[AR67GTX]

If you don't notice the difference between 3.23 and 3.55 with the same size tires.....

I sure do.

I agree. I changed from a 3.23 to a 3.55 in my 67 GTX and it’s enough of a difference to definitely notice. My GTX has factory air so it’s pretty heavy and with the 3.23 the tires would hook up too early off the line and pull the engine revs down to where it had to slug or fight its way back up the rev scale. With the 3.55s it doesn’t slump when the tires hook up and have to struggle back up in rpm - it just keeps pulling and reving.

 

[68GSS440]

I didn't see anyone post the obvious (to me) answer. if you're going to spend the $$ on a different rear gear set, instead spend it on a Gear Vendors. a 3 speed automatic becomes 6, a 4sp manual become either an 8 speed or a dual range 5 speed. I've used them for over 25 years, with rear-end ratio from 3.55 to 4.10 and once with 4.56 in a 54 Savoy gasser with a 331 Hemi with a 4 speed ( younger and crazier )...
your car - your choice