Stock gear or 4.10 gear for street ?

[dpok69]

Just had my tranny done with the correct speedo gears installed and BRF code. But my speedo still reads incorrectly (speedo reads 50mph when actual speed is like 80-90mph). There is a possibilty that the rear gears are a 3.08 from a monte carlo the previous owner used to have.

My car from a standstill cannot fry its tires at any moment unless brake boosted (max boost 18psi per run). I was told that a 4.10 gear works good on these cars from the buick tranny shop. So rather than going to the stock ratio, should i upgrade?

[azgn]

a bigger gear will not improve the "tire frying" capability of your car......these cars don't make power until they are on boost........a looser converter will get you more boost quicker

a 4.10 on the street would be a real pita.....the only reason to change from a 3.42 would be on a race car to meet certain rpm/tire size/transmission parameters in the 1/4 mile.....

[UNGN]

If you have 3.08 gears, makes sure you still have a 8.5" rear end. A monte would have only a 7.5" rear.

For a turbo car, 3.42 gear cannot be beat. If I were changing gears on a car that saw street duty, I'd go 3.31:1 or 3.23:1 so I could hit 120 with 26" tires, without having to shift into OD. With 4.10's you'd have to shift into OD in the 1/4 mile (unless you had monster 29" tall tires).