What kind of hp gains can you expect from swapping the intake and exhaust cams in a gsr with those from a type r (adjustable sprokets included)? Ive read that unless you have a large throttle body/ injectors / headers (etc) you wont notice too much. Also, has anyone put civic r cams in a gsr, apparently they are worth a couple more ponies as opposed to the integra spec ones.

 

You will feel the different, but the most important thing to swap out is the GSR intake manifold and the header. The GSR IM is not meant for high RPM, so you won't get the most out of the R cams. Also, injector is not necessary if you are only going with R cams. I think all the B16 and B18 have the same injectors anyways.

 

Will you lose much low end torque with the r im? I heard that the r im only makes more power after 8000 or so....

 

You won't loss too much, at least not noticeable with your *** dyno.
But the gain about 7500rpm will be well worth it.
BTW, you won't see too much gain with TypeR cams over the GSR cams in the low end anyways.