look to the left of the exhaust manifold, should be a little plate attached to the engine, or an imprint, I can't remenber which that has the engine code..
b18c1 = GSR engines, b18c5 = Type-R engine (note: you'll see ppl say ITR a lot, that'd be a type-r, so you're less confused.)

there's the off chance that it's a japanese crated engine, which, if someone can correct me if i'm wrong, doesn't tell the difference between the 2 engines on the code... there may be a way I don't personally know of, or run it on a dyno and find out what's going on.

p.s. welcome to HAN :cheers: