its not a matter of the engine, its your hp goal. honestly 300 isnt shit, you have to understand there are 1700lb civics putting 350 to the ground riding around EVERYWHERE, and thats fucking fast, damn near 1k lighter than you and more hp... if you want to own the middle weight class.... (boosted civics, srt-4's, cobras, ss's, stock vets... ect..) you are going to need a minimum of about 450, and some weight reduction. dont worry about that kinda stuff though, 300 is good, it will handle the ricers running around, your factory gt mustangs, factory 350's and stuff like that, but your big boys in the middle weight class will smack your pee pee in the dirt. I live in greenville sc, and the middle weight class around here is pretty nice, we have some 350hp civics, 400hp srt-4's, so on and so forth, my 240 puts 446 to the ground and holds his own 95% of the time, the ones you can never tell what is done is your mustangs, ta's, ss's and shit like that... stick with the sr, it will make all the power you want.