not to sound like an ass, but thinking that you can spin an EJ25 reliably NEARLY as fast as an EJ20 is just maddness. the 2.5 ROd if just TOOO long, it's built for low end torque nothing more. You all bring up the torque issue. Torque is eliminated with a properly geared trans(which the RS very much does NOT have). well anyhow i'm not gonna sit here and paper race. but look at the foot per minute od speed of a EJ20 @ 8k rpm and look at the FPM rod speed of an EJ25 @ 8k RPM
you might be shocked at what you find, also why do you think the USDM sti block has a 7k RPM redline.