I am about to purchase a 1985 Iroc-z it is an automatic 305 TPI. I am planned on making it louder and faster. I was wondering what would be the best thing to do to the engine to give it that extra power. Any replies will be helpful. Thanks

 

I would start with a set of ceramic coated headers and a free flowing
cat-back exhaust. A torque converter will prolly give you a pretty good kick off the line, But if you really wanna start with the engine without digging too deep into it a lot of people swear by the Holley Stealth Ram

 

Not to mention your basic...plugs wires, cap, rotor, coil, timing, ect.
Fuel Filter, just your basic tune up.

Headers are a pretty nice add on for power. Cant beat a free flow exhaust.

 

Go here ...

https://www.thirdgen.org/tpimod1

I am pretty much doing the same thing you are doing. I don't want to go crazy with my car ... at least not just yet ... but I do want to go faster. This is a good checklist that starts small and basic and then goes onto the more complex stuff. Plus the basics ... headers, cat-back, aftermarket intake ... don't require reprogramming your ECM, which is good because from what I have read, the only way to do that the 'right' way is to do it yourself and tune it to your car. I'm not ready for that yet, but plan to learn eventually.