How difficult is it to hit around 170whp without going through the ls/vtec route? What modifications would i have to perform while keeping my engine naturally aspirated?

 

Well there's a dude named HX_Guy had an all-motor B20Z non-VTEC with around 170 whp. His setup was i/h/e, 11.5ish Compression, crower 62404 cams and a SAFC and FPR i think. With a port and polish he could probably have gotten around 180 whp

 

IMO yer better off goin lsvtec if its for the money issue.. fer about $400 or less u can pick up a bare GSR head and prep the heck outa it.. and run near or over 200hp.