big valve questions

[fomospede]

hey guys
ive bought some ferrea valves stock intake and plus 1mm ex
the ex seats can just be machined up or do i need to replace seats?
also do i need heavier spring rate or will new oem get the job done
running hc s2 cam

[Lquad71]

not sure if the seats need replacing or not but you should be fine on spring rates with that cam.

[JH Racing]

the seats can be machined they do not need to be replaced the ferra valves are heavier than OEM so if you are a rever stiffer springs would be a good idea.