I would do some suspension mods too. Help plant that power to the ground so you can hook and book.

 

Hey guy. There are a dozen other post like this one on this forum. Some even on the same page. You can also use google to help you. Picking a cam is not a good idea until you know what set up you are going to try to run. If its a auto car that will also be a factor on your converter as well.

If you have a strong LT1 then it doesnt take much to beat a STI. They are strong out of the hole but need good air to perform at the best. A well bolted LT1 with good tires can run the same times as a stock STI. Add some juice and its game over.

 

im just happy you are going after a subaru...

My sig used to say, "the reason that subarus dominate in rally is, you dont take nice cars in the dirt"

 

The STI is a great car dont get me wrong. They are fun to drive and do pretty darn good in rain and mild snow (as long as you are not running DRs) And they still get decent fuel mileage but then again they are high maintenance.