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??? on porting exhaust on Katech heads

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Old Jan 6, 2006 | 06:46 PM
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Default ??? on porting exhaust on Katech heads

Would it be beneficial to finish porting the exhaust ports on a set of Katech stage II heads,to the same size as the header gasket. Or will I hurt the flow or design of the heads. I'm planning on installing the heads soon and if I need to finish porting them, I can do so before hand. Any help would be greatly appreciated. jwcej@msn.com
Thanks, have a great weekend and God Bless Our Troops and the U.S.,
John Junkins
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Old Jan 6, 2006 | 10:48 PM
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Typically, ports can be opened up if necessary to match the pipe, not the gasket (which is often oversize), but only at the top and sides (better the port should be a bit smaller than the pipe rather than at all larger, which would create turbulence). On the bottom it is pretty well universally felt that any step-up from port size to the header should be left intact, as there is very little flow in the region, but power-robbing reversion pulses tend to move up this low velocity region, hurting lower RPM output.
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Old Jan 6, 2006 | 10:55 PM
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I agree with Bill and have done that.
Gasket bigger than port leave that alone, header primary smaller than port then portmatch primary (done that on my MACs).
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Old Jan 7, 2006 | 11:58 AM
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Thanks, MadBill and PredatorZ for the info. I really appreciate it.
Thanks again, have a great weekend and God Bless Our Troops and the U.S.,
John Junkins
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Old Jan 7, 2006 | 01:37 PM
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Contrary to popular believe, the exhaust side is more sensitive than the intake side, when it come to porting. If the head is already ported, dont touch the thing unless you are pro. I will modify my own work, but would leave modifing someone elses work to a pro or that person.

Brandon
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Old Jan 7, 2006 | 02:45 PM
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The heads I received from Katech are a VERY nice set of heads. Even the bosses in the inside of the intake ports have been removed. I was just wanted to check to see if I could make the exhaust side a little better. I appreciate all the info. I'm receiving on this matter. From all of the input I'm just going to leave them alone.
Thanks again and God Bless Our Troops and the U.S., John Junkins
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Old Jan 8, 2006 | 10:02 AM
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One last question, My car is basically a car show only car with a little to no racing. I was just going to install them for brag rights alone with all the other stuff I installed on the car. Would it be even worth it to install the heads. Would I notice that much difference. I also have to run cats to get my car inspected. Or would it be worth it just to install true duals instead. OR just nothing at all.
Thanks again and God Bless Our Troops and the U.S., John Junkins
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Old Jan 8, 2006 | 10:19 AM
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You mean heads only, stock cam?
If so no, not really. AFR 205's have been swapped on a stock vette and only could do 22 rwhp, so Katech would not match that.
Cam is definately needed.
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Old Jan 8, 2006 | 10:29 AM
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I have a TSP 228R 228/228 .588/.588 112lsa cam in my car now. Weiand intake , headers,tuned and all the bolt on you can buy. I just wanted to know from someone whom already done the change. If it would be worth it. In my case before doing the work. Thanks for the info Predator-Z Any help is greatly appreciated.
Thanks again and God Bless Our Troops and the U.S., John Junkins
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Old Jan 8, 2006 | 10:39 AM
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Then yeah, those heads should get you a good 30+ rwhp with a good tune.
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Old Jan 8, 2006 | 10:55 AM
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Predator-Z, Thanks for answering my questions. I will start on my car when I get back from Dale City Ca. in two weeks. Again THANKS!!!
Have a great Sunday and God Bless, John Junkins
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Old Jan 8, 2006 | 12:23 PM
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John, I'm guessing you're the person I talked to on the phone on Friday. FYI for everybody else, I said don't modify our heads.
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Old Jan 8, 2006 | 04:20 PM
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Jason, Yes I'm the one you talked to on Friday. Just checking with the other racers on their opinion. They are a VERY nice set of heads. Just trying to get as much as possible out of them before installation. And I'm going to take yours, Predator-Z and MadBill advice and leave them alone.
Thanks again, John Junkins
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