hey guys getting ready to start doing some upgrades to my 99z just a thought if I go with headers should I do headers hi-flow cat and a new exhaust system all at once also what brand headers and exhaust you recommend and when it comes to replacing pullies does it make that much of a difference and which set would you recommend thanks again money is not a problem thanks for the answers in advance

 

Lid, catback, and Long tubes..i wouldnt be so worried about your cats...even high flow ones dont produce much more power over stock

 

Lid,filter, and catback. Before longtubes, try working on stiffening up the car because that is one the most important things to do.

 

long tubes are the way to go if emmissions are not a worry

as for the pullies, the standard underdrive pullies will not work on an LS1...the only company that i know of producing ls1 pullies is ASP

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