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My head is currently off to install a thicker head gasket. I will take this as an oppurtunity to do some head work. As of now I have a set of tomei cams and GcG highflow coupled with the supporting mods. Im interested in getting some more flow through the heads. A port and polish seems like the best if not, the only way to go. I have even heard some people say to only do a port and not a polish cause it messes with the atomises of the fuel? either way can all you tech boys guide me through on the best option to go? And also factoring in that budget is a big issues :rofl: I live in perth :/ and have not heard of any good places that can do the job. Can any1 suggest one for me? Any idea as too how much it would cost?

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usually around the $1K mark

have also been told by my mech that on FI motors the rewards arent really that great compared to doing this on an NA ... and for the cost .. im with Ash

i have done a knife edge on the spliter between the valves per inlet port on my rb25 head for my rb30 ... but thats it

would get more gain from porting if you coupled it with bigger valves - but thats big dollars - machining and fitting plus port plus parts

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I don't think it's worth it until you are going for a very big turbo and lots of boost. All you will be doing is increasing the time you take to spool up (more lag) and wont get any benefits.

I got quoted $1200 to match port and polish and reduce the compression ratio. This would be ok and a better idea than using a thick head gasket.

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