Can anyone describe the driving characteristics of the stage 1 and stage 2 cams ??
This is what RSI say,
"Stage I will work great up to 300whp or so and is a GREAT daily driver cam. stage II is for folks wanting to rev things out with factory type turbo's and who have headwork etc...working upto having a header"
I think they explained it pretty well. the stage 1 will be pretty good at most rpm and fall off at high rpm, but is still plenty good enough for 300hp. The stage 2 will not have quite as good low rpm torque but will carry the power band high up in the rpms and has the potential to produce more high rpm power.
The way I look at it is like this, and this is a very simplified version, cam theory is way beyond what I can understand. So here's the cliff notes.
With an 8v head like we have you can't get something with out sacrificing something else. For instance: The volvo T cam has amazing low rpm torque, but falls on it's face at higher than 4.5k rpm. The factory K cam makes pretty good power up in the higher rpm, but isn't as good as a T cam at low rpm torque.
If you're using an adjustable cam gear you can within reason shift that powerband up or down the rev range. So by retarding the cam you are shifting the emphasis on the exhaust stroke making the power band shift higher in rpm (not necessarily getting you more power just moving it) but loosing a bit of lower rpm power. By advancing a cam you're shifting emphasis on the intake stroke allowing the engine to inhale more which in turn shifts the power band to lower rpms, but loosing a bit of high rpm power.
Understand that and you will understand why the stage 2 cam isn't sold as a daily driver cam. It's a hot cam that emphasizes peak power at high rpm, but in turn sacrifices some power at lower rpm. Losing low rpm power is hard on a daily driver, you're not going to get to rev out to 6k between the stop signs too often. It's even more so on an automatic which engages the torque converted at around 1900rpm effectively bogging your engine down until you get up to speed to get into your power band.
It's easy to say get the stage 2 because it will allow for more power. The real question is how are you going to be using the power, what rpm range will the power do you the most good, and what other mods will you be doing to justify the beefier cam.
TLDR:
Your turbo alone (mitsu 16t) and factory manifolds tells me that you're not going to be in the more than 300hp range, and I would recommend the stage 1 or ipd turbo cam. As Mike's shown it takes about 2x the turbo (holset h351) and custom manifolds to make 300 hp on his chips.
You should have all the information you need to make a informed cam choice now, maybe read it twice. Good luck.
