I don't know about 4.10 gears, but in early 1969 I bought a new 69 Barracuda 340 Formula S 4 speed with 3.23 gears and NO options. Manual steering and brakes. The only mod I ever did was headers. I did a lot of street racing, and I can honestly say that I never lost to a 383 RR or Super Bee. Maybe I just happened to have a 340 that just happened to fall together perfectly. Maybe, since it was a fairly early 69, it had the slightly hotter 68 340 stick shift cam. I can only tell you that it ran like a bat out of Hell.