Okay I guess this confirms it. The SR20 seems to run best for Drifting at around 350-370 HP. I have around 4 Silvias about that Range and I Love them. I'm finding out though the 180sx's Near 50/50 weight distribution is awesome. I finally got a 270RR today, so I guess my last Silvia will be a S13. I'm so behind, I'm backed up and haven't fully tuned my S15 yet.