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i am getting tuned in 2 weeks and i cant afford headers.........so i can goto my team shop and get my stock ones ported for free

is this a good idea?
pros and cons? thank you!
 

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i think porting the ej20 heads is a good idea, especially if you can get it for free. they will flow as good if not slightly better than a set of JDM or RA heads. and it'll probally take a while to get those unless you get them used. im not sure if there is different degrees of port jobs, but you can find how axis does theres on vivids site. oh and the result will vary depending on the size of your turbo and how aggressive of cams you are using.
 

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I have a stock header that is being ported and installed today. I checked to see how much iron would be removed by placing a new gasket over the pipe entrances by the cylinder heads. It looks like there's 1/4" or so of overlap, meaning the it'll take 1/4" of grinding to get the header to fit the gasket.

My car is tuned for the Borla header that is being replaced, so I'm worried that the stock one might throw things off. Therefore, I'm having it dynoed right after the ported header is installed. I'm also having the car videoed before and after, so I can hear the difference in sound. I'll post the results on Sunday.
 

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Quick summary:
The porting job was excellent. The 1/4" of iron that overlapped the gasket is now a polished, gradual taper. The car sounds a lot meaner without the Borla header. It is much deeper and less metallic and raspy. The graphs show that the turbo is spooling about 200rpms sooner than with the Borla. That doesn't quite live up to the hype, but it's better than nothing. I lost about 10 ft/lbs of torque, but the change in sound is worth it. I'd say if you can do it for free, you have nothing to lose. If you see just how much of an obstruction the overlap is, you'd want to remove it.
 

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Here's the dyno sheet. The runs in red and blue are the same, with the dyno set at two different loads; disregard the red one. The black line represents the car with a uncoated, unwrapped Borla header. It looks like I lost some torque, but the turbo spools up a little faster. I have another sheet showing the current boost, but I forgot to get a graph of before/after. I have some video clips of both setups, which will be up soon.
 

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Are they going to port the header or sandblast it? A lot of the local V8 guys get their intake and exhaust manifolds sandblasted, not ported. This just makes the runners smooth as glass so they will flow better. Perhaps FHI has better casting techniques for the manifolds than Ford or Chevy . . .
Either way if it is free, do it it wont hurt anything at all.
 

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I got the image to work from my home computer. Regarding sandblasting, the company that does it calls it Extrude Honing. It would be a good idea for Suby headers, for the inside of the pipes is kinda rough. However, it costs at least $450, and to gasket-match the header is extra.
 
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