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Discussion Starter #1
Hey all, I have a ported 5s head and wanted to mate a 98 camry header on to it. My question/problem is, that the exhaust port on the Head is about a quarter inch to half inch bigger then the header Inlet ports. I was wondering if I had to port the header to at least match the head ports?

And if so... how exactly should I port the header out? thanks
 

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Discussion Starter #3
I dont mean the actual tubing. I mean just the port entrance. There is enough material to open up the entrance. There is also a 90 degree lip also, i want to dremel it down to a diagonal slope rather then a sharp 90 degree lip.
 

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you mean port the flange? You could, but again you have to be careful because the actual sealing of the header tube to the flange is on the head side of the flange, not the primary side. So if you round off those edges that butt up against the head then you are going to be removing welding, which besides being more difficult, will result in less material holding the primary to the flange.

BC
 

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you ported your ports HALF AN INCH larger? you're trying to use an oem manifold off a camry?

.. some things arent adding up..
 

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From what I have heard in an NA application it is actually benificial to have the exhaust ports smaller then the header ports and not make too smooth a transition. It keeps the exhaust gas from reversing back into the cylinder. I could be mistaken about this though... that's just something I read somewhere. Tom's right, 1/2" is alot and may be counter-productive. You should get a tubular header with larger pipes then your exhaust ports. What is the standard pipe size for 5sfe headers anyway?
 

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Discussion Starter #7
well i might have over guessed how much bigger the exhaust ports were... but they are bigger then the header ports.
 

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Mrturrari said:
From what I have heard in an NA application it is actually benificial to have the exhaust ports smaller then the header ports and not make too smooth a transition. It keeps the exhaust gas from reversing back into the cylinder. I could be mistaken about this though... that's just something I read somewhere. Tom's right, 1/2" is alot and may be counter-productive. You should get a tubular header with larger pipes then your exhaust ports. What is the standard pipe size for 5sfe headers anyway?
This is quite correct. Matching the port sizes is not good for power. Should you be able to get the larger header pipes, you may wish to slot the bolt/stud holes on the flange. You could then align the header so that most of the port mis-match occurs at the port roof instead of the port floor.

Update us with results when possible please.
 

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Discussion Starter #9
Ok, the head ports are actually gasket matched. So any recommendations on what header would be good? Does the header port size have to be bigger or the header runners?
 

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celicaguy13, based on your last question, are you planning to use 1) an OEM header, 2) an aftermarket header, or 3) a custom header from your local muffler shop?

Based on the fact that you did headworks to your exhaust port, i assume that you did same to the intake side, and that you plan to upgrade the exhaust system to fully benefit from the headwork. Am i correct?
 

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Discussion Starter #11
Correct the both intake and exhaust ports were ported. At the moment im using a 99 camry header and am planning on upgrading the exhaust as well. I would like to get maximum hp but also keep the exhaust semi quiet. The camry header is stock a tubular type.
 

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If the camry header is tubular and not cast, find out from your muffler man how easy/difficult it would be to
1) cut the headers from off the flange
2) enlarge the flange holes to the required size,
3) flare the camry pipes up to the required size (over a length of 1" to 1 1/2")
4) weld back the flared header pipes to the original flange.

Find out from him if he can do it, how much it would cost, and get back to us ASAP.
 

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celicaguy13 said:
Well i'll look around for a better muffler man. But i'll look around to ask questions though.
You may also check a local machine shop, or metal fabrication (welding) shop. The ability to cut, flare, and weld is what you are interested in.
 
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