The car sounds really good man, its a nice smooth acceleration, And i noticed the same thing after i put on the gr2's with Ground control coil overs on. i dont spin as harsh in second gear like before most of the time it would just pound off the rev limiter when i punch it at about 35-40mph, now depending on the road it will still do that if on a crappy road, but on a nice road it will spin the tires but pull hard at the same time, i mean i go from 35-60 in about 1.3-5 seconds or so in second, i even spin third gear even shifting slower but once that clutch comes out with the reves still up the tires will spin to about 70mph. this is on falken ziex 195's in good condition with 75% tread left. So yeah the suspension holding the back up and the front down helps alot.
Although its hard to say how much power your making, Im at around 265-275whp on my t25@15psi but my car weighs only 2200 lbs so weight has alot to do with it, cuz it seems like my car on a T25, JDM, S4's, Flywheel, would take you out pretty easily, haha, here is a vid of mine that was on 8psi, i havent taken a vid at 15psi yet so it pulls a little quicker than in the video. Let me know what you think, You just have a lot more weight to pull around. I would definetly say your probably up in the 325-350whp range but its hard to say. I can definetly say your top rev holds a more steady acceleration than mine, cuz around 80mph in mine in third the power has already fallen off so from 60-80 is about 1.5 seconds while it takes about 1 more second to go from 80-90, haha
http://www.youtube.com/watch?v=_LVBC3LG_8I
Although its hard to say how much power your making, Im at around 265-275whp on my t25@15psi but my car weighs only 2200 lbs so weight has alot to do with it, cuz it seems like my car on a T25, JDM, S4's, Flywheel, would take you out pretty easily, haha, here is a vid of mine that was on 8psi, i havent taken a vid at 15psi yet so it pulls a little quicker than in the video. Let me know what you think, You just have a lot more weight to pull around. I would definetly say your probably up in the 325-350whp range but its hard to say. I can definetly say your top rev holds a more steady acceleration than mine, cuz around 80mph in mine in third the power has already fallen off so from 60-80 is about 1.5 seconds while it takes about 1 more second to go from 80-90, haha
http://www.youtube.com/watch?v=_LVBC3LG_8I