If you want something streetable and a good amount of fun, don't go over 250rwkw. Just starts getting a little crazy for the road then.
To give you an idea, when I get my R34, I'm building it mainly as a road car, but want to use it to start competing in the Autotest series. Don't want huge power for that as most of the tracks are tight and twisty.
To do this I'm going to start with a little over 200rwkw and see how that goes first. To get there I'm getting the following
- RB20 wastegate actuator (increases boost to 10psi)
- FMIC
- CAI
- High flow filter
- Power FC (if I can find one )
- 3" turbo back exhaust
- Iridium sparkies
- Tomei Fuel pump
- Surge tank
Then I will work on suspension and braking as well
This will give me between 200 and 210 rwkw and be pretty competitive and a lot of fun to drive. Since I've still got the stock turbo, it will spool up quickly and give good response. The only other mod that I may also add is a front facing plenum. This will once again increase the response that was lost from all the fmic piping going over the top of the engine.
I will use it like this for a while, and if I feel I need a little more of a kick, I will look into some more options