Right now I have a strange 12 bolt that came with 3.90 gears from motive. They make a lot of whining noise, and have heard the same from several people. I have had to shops look at them, and are in perfect condition. I was thinking of switching to a gm 3.73 or 4.10 gear to take a lot of the noise away. Any suggestions. My mods are in my signature. And how much difference in performance would I see from going to 3.73 or 4.10??

 

You have a 383, and a 700R-4, in a third gen. And you're seriously considering 4.10:1 gears? How big is your cam?

 

nothing is wrong with a 700r4 and 4.10 gears. My cam is a zz409 from tpis .520 lift 226 duration 112 lobe separation. And its a roller cam. Those specs are with 1.5 rockers, I have 1.6 so it bumps it up a little