Welcome to Hondaswap ! and there are many many upgrades you can do to the car without motorswapping and the gsr engine is a great one, same note most your regular bolt-on stuff has little to 0 performance gain other than sound ex Intake/header/exhaust (within moderation cheaper stuff can actually lose power over oem) , if you really want to do it id recommend maybe power adders ex: turbo/supercharger/cams but would also need the supporting mods , post some pics up of your ride man !
looks like a sweet ride, what happened to it ? car appears to be modified some already, lol and again how much money you want to invest and power goals go a long way on what you should do , if I was to have a gsr and wasnt my daily and I was going to modify it for power without swapping I wouldnt touch a single thing on the car and go a nice turbo setup on low boost and a quality tune and supporting mods, but 5 first cheap mods that has nice performance gain in a N/A stockish honda is always I/H/E , if shocks are good then like 1.5-2 inch lowering springs or coilover sleeves if blown then do coilovers while at it , short throw shifter, a actual wheel/tire combo can make a huge difference, a new set of STOCK rotors with a nice quality performance pad (avoid 100% slotted/cross drilled fad you lose surface area and have cheese graders for brake pads) , I mean really its all about how your power goals and how much you want to spend, 200 whp is more than plenty for streeting
preach it , when I had the ST at AMP at the track event in the Auto X I got spanked by a 91 crx DX with a cone filter on the stock intake and the interior removed and not very expensive ground control coilovers and a meaty wheel/tire combo and very consistent driving, whopping like 95-100 hp in 1991 lol shit prob had 200k on itive watched a guy dominate autox with an ls integra with an intake, some mild suspension, and a decent rim/tire