Originally Posted by Servin_upaces
Hey guys, Bare with me this is the first forum I've joined. Just bought an 87 rx7 fc and want to make sure I do everything right the first time. I know I need to get matching injectors, bov, recuirculate, tune etc.. but just talking strictly turbo chargers how big does it need to be to make significant hp? I know it needs to be big. I was going to buy a t28 from an s15 off my buddy I worked with at Nissan and yes you guessed it.. it was going to go on his 240.. (s13). I did my research and I know I would need two so I didn't buy it. Anyways, what turbo(s) should I get? Single vs twin? Just want to do this right!
You have omitted a lot useful information, but your first hurdle is budget.
300whp is not a lot for these cars, but you need to change a lot of things and spend a decent amount of money to make the "jump". Also, almost no one is doing twins on the FC...even FD guys are getting away from twins. A modern single turbo is just as good if not better in most applications.
Strictly referring to the turbocharger, I'd recommend one of three choices:
Cheapest: hybrid turbo. BNR stage 2/3/4 will get you to 300whp.
Budget conscious: Garrett GT35R or comparable Borg Warner SXE.
Price is no option: Borg Warner EFR.