Re: Porting na head
You are correct when saying getting bench flow tests are the only way to show that the porting was successful. I used a machine shop in Appoka, just north of Orlando. It is a small shop that has done a lot of high horsepower WRX's, SRTs and others. They did not benchflow the head, but we did not make big changes to it either. Primarily, cut the port to match the intake, smoothed out the metal and the like. I trusted that they knew what they were doing and my experience in racing heads, those minor changes are always good ones.
I am porting the TB to 55mm. I am not sure what the true measurements are for my TB is to begin with. There is a internal sleeve where the butterfuly closes. I thought the stock bore was 47mm, but I have heard that in some NA cars built in 06 and up, (mine is a 06) they have a 52mm bore. If so, some may not think a 3mm additional bore is worth it, but actually it is. I don't have my numbers anymore but when I calculated it, a 55mm could flow a max of 289hp at the crank on our motor. Someone else may be able to correct me on this.
Once I get to the dyno, I think the real numbers will show. (Good or Bad). Only a few more weeks away.
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