I drive a 2000 GMC Sierra Z71 with a 5.3. I am wondering if it is worth it to go to a set of long tube headers from shorties. I want to be able to keep it catted also, is that possible. Or would I get more out of it be just re-gearing. Let me know. The truck is going to Nelson next Friday so I need to know ASAP so that I can get the parts in and installed. Thanks.

 

One or the other? Gears. What is your current ratio? With the 35" tires you should be lower than 4.10's, like 4.56

 

As of right now the ratio is 3.73. Eventhough it is a daily driver do you think 4.56 are the right choice? I do but people keep telling me to stick with 4.10's for the revving.

 

4.56 would put your rpm's back into the stock powerband with 35's. Some go with 4.88's for a little better acceleration but you should be fine with the 4.56's.