Hi,
You can grab 50HP+ over stock with Bolt-on’s, Tuning, enhanced with lower gears.
I’ll go a little deeper, see what you want.
After the ‘bolt-on’ level, it really begins getting more expensive, and whether Cams & porting, Or boosting, the car needs balance, built equally to utilize the additional power & remaining safe and reliable.
I’ll put FI on the conceptual table, for information only. if you ran dished pistons & dropped C.R. to that of the 03’-04’ Termi’s (8.5:1), if a Tekskid or WAP block you could boost it to 400-450HP running a Roots or Centrifugal supercharger & keep a mostly stock topend and sacrifice no drivability.
There’s a few areas I’d suggest improving the build if you’re going “ground up”, regardless...steel rods, forged pistons, ARP fasteners, as a generalized statement.
As I understand it, the 01’ SVT’s predominantly ran the WAP block, but there were older Tekskid blocks that made there way into them. Did you confirm it as Tekskid?
Is the car currently bone stock, or have some bolt on modifications?
Best!
-John