Im from australia and running a n/a 3800 like you there is alot you can do alot of it yourself.Half the prices below for US $
My car is a vn same engine ive fitted pacemaker extractor's and a 2 and half inch exhaust with high flow cat i did all that myself for $400 worth of part's .
I used a dremel with the right bit's and have made my throttle body bigger and also did some on the inlet manifold ( i dont want to touch the head's yet ) Cost of dremel and bits $200
I have a K&n inbox high flow filter connected upto a 4 inch cold air intake feed going to the front of the car.
Do a complete service of your car my vn on the dyno after a complete oil filter and change using the best oil i gained 10Hp on a dyno before adding other mod's so a service help's
When servicing you replace spark plug's (use a cold heat range)
Use performance lead's replace fuel filter ( EFI ? mine is efi electronic fuel injection)
Run a higher octane petrol over hear we have 93 standard and 98 for premium i wish we had 100 + on tap.
because my car is EFI i put an aftermarket chip in and that removes the revlimit / speedlimit
There is alot of little thing's you can do that all add up
all i know is i wish holden imported the 3.8 litre turbo instead of our N/a 3.8 engine.
Im converting an old turbo into a belt driven supercharger and should be able to run 13Psi after a dyno tune and fit bigger injector's etc and a metal shim headgasket all for $1000
