Cams and Gears

[NPIGT]

I was wondering why when you switch cams, such as the VT Stage 1 cams they recommend a gear ratio of at least 3.55. How do the gears effect the horsepower you put out?

 

[DropTopPony]

my guess would be that most cams pick up hp in the upper rpm range and having the right gear will get you to the right rpm's to make max hp.

 

[Dark Knight GT]

my guess would be that most cams pick up hp in the upper rpm range and having the right gear will get you to the right rpm's to make max hp.

Bingo. With these higher performance cams, the torque curve shifts to being a bit higher. Having anything less than 3.55 gears will result in more time spent below the new torque curve, and thus it can hurt performance and make daily driving a bit of a PITA.

 

[90RanGer]

I'm still running the stock gear ratio in my car, I will upgrade but havent had a chance yet. It seems fine, its pretty obvious where the power band is in the car, but daily driving is just fine with stock ratio and those cams.

 

[Dark Knight GT]

90Ranger, you're also running a Bullit intake with Stage I cams. Not the stock intake setup with Stage II cams. The Bullit intake helps to pick torque up on the low end and improve throttle response over the stock intake. That, and the Stage II cams have a bit more lift for higher rpm band power than Stage I's. Not saying its a "world of difference" from your setup, but different none the less.