On FP's site, it says 84mm surge port vs 64mm...what does this mean?

It also gives an option for three wastegates; stock evo 9, 18psi, or 25psi? What would be best for quicker spool?

Thanks

 

64mm is a stock sized inlet. Some people have compressor surge with this housing. The 84mm housing is FP's solution to this problem. Get it.

WGA doesn't have much to do with spool. Choose one based on your target boost. For a pump gas car an 18psi actuator will do well. The 25psi is good too but you won't be able to run lower than 25psi. One part the wga plays in spool is by the preload. By adjusting the eyelet on the end of the arm you basically hold the gate closed tighter and longer which can help spool up and with holding boost up top.

For most green users: 84mm cover and 18psi wga

 

Can they upgrade an OG Green to the 84mm cover?

 

Sure can. Well, it is doable for FP to cut the 84mm surge port cover to fit any 16G stock based turbo, I think. Whether in actuality they'll do it or not, IDK, ...you'd have to call their shop. There are a couple peeps on here running that compressor cover on a stock IX turbo. I know that for sure.