Author Topic: Header install  (Read 5275 times)

Offline 1Chevy

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Header install
« on: March 07, 2016, 11:00:48 PM »
Pick up some flowtech headers for my 82 c10 454. Got them sand blasted so i can recoat in just some VHT cleat coat, i like metal finishes. Big problem ive ran into is i brain farted and didnt check exhaust port shapes now have circle port headers with square port heads. Thinking they should still work as long as the headers ports are bigger than the heads. Any thoughts? I'll have to check to tomorrow as i just kinda unbolted a few things Sunday just to start the process.
« Last Edit: March 16, 2016, 01:14:38 PM by 1Chevy »

Offline LTZ C20

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Re: Header ports
« Reply #1 on: March 07, 2016, 11:53:12 PM »
It's fine to have circle port headers with square port heads. My truck is the same way. A set of sqaure port headers will be extremely expensive and won't really be worth the cost unless you are doing drag racing where tenths of a second and precise tuning actually count. You will be just fine.
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Offline 1Chevy

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Re: Header ports
« Reply #2 on: March 08, 2016, 12:21:59 AM »
Great thanks! Would the gaskets that came with it be ok? Or would something better be recommended for the situation?   

Offline Stewart G Griffin

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Re: Header ports
« Reply #3 on: March 08, 2016, 06:52:00 AM »
i think they make adapters?    But apparently it doesn't matter as LtZ pointed out.

Offline LTZ C20

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Re: Header ports
« Reply #4 on: March 08, 2016, 09:05:57 AM »
Depends on what came with them. I experimented using different types of gaskets trying to get the best seal. I eventually found that the paper gaskets with copper spray worked the best. I got 2 sets of paper gaskets and can of copper gasket spray, like what you would use on head gaskets. I layed all for gaskets out and copper sprayed 1 side of them all. Then when the copper spray was tacky, I took 2 gaskets and put them together with the 2 copper spray sides touching each other. Like a big autmotive peanut butter sandwich. The paper gaskets are the white bread and the copper spray was the peanut butter. Then I let the sit with heavy weight on them for at least 2 hours if I remember correctly. Since then I haven't had any issues. That was for just my application tho. There's a rule of thumb that you are supposed to match the gasket port shape to the port shape on the head not the header. Or its opposite and it's supposed to be match the gasket port shape the header port shape not the head. I can't remember which way it was, but I'm fairly curtain it's match gasket to the head NOT gasket to the header. Hopefully someone will chime in who knows the correct rule. Which kind of gasket came with them?
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Offline 1Chevy

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Re: Header ports
« Reply #5 on: March 08, 2016, 12:52:29 PM »
Good info LTZ. I measure the ports and the headers are bigger than the heads. I didnt consider which gasket to match. Sounds like i would want the gaskets to match the heads

Offline Burkhalter

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Re: Header ports
« Reply #6 on: March 08, 2016, 04:47:03 PM »
I have the SB so it's not the same motor, but should still apply. I have square ports on my heads with round on my headers. I used copper gaskets with square holes and it sealed up nicely. something you could do if your having troubles sealing it up. Would be getting a piece of copper sheet metal and making an "adapter" by cutting out circular holes and then matching the outer silhouette of the normal gasket. Then just put both pieces on.
'85 Chevy K10 361ci sm465

Offline LTZ C20

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Re: Header ports
« Reply #7 on: March 08, 2016, 04:51:45 PM »
As long as you match the gaskets accordingly and I recommend putting anti-sieze on the bolts or studs depending on what you use, you should be fine. I ended up using studs and they clamp better than bolts. Also, tighten them up when you put them on, remember they only need to be around 35 ft lbs I think is the torque spec. When you run the engine, let it cool for like 2 hours then recheck your torques again, and then again after driving 50 miles. And then again after a week or so of driving. You will find they might tighten a little more after a few heat/cool cycles. Even if they only turn 1/8 - 1/4 turn, re-checking them helps prevent them from rattling loose, warping and blowing out the gaskets. You will want to do this for both the flange mounting bolts and the 3 collector bolts.
« Last Edit: March 08, 2016, 04:55:52 PM by LTZ C20 »
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Offline 1Chevy

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Re: Header ports
« Reply #8 on: March 16, 2016, 01:13:32 PM »
Finally got passenger side installed. Been lazy. Had no fitment issues luckily.about 10 mins getting that side in minus disconnecting the starter wires.

Offline Burkhalter

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Re: Header install
« Reply #9 on: March 17, 2016, 06:05:10 PM »
I don't know if you're planning on wrapping those for heat and sound, but if you are I would like to suggest getting the tan colored wrap. Yes, the silvery white looks a little better but if you ever drive on dirt roads the tan stuff will look better longer. Those are some nice looking headers hope you enjoy them.
'85 Chevy K10 361ci sm465

Offline 1Chevy

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Re: Header install
« Reply #10 on: March 18, 2016, 12:51:00 PM »
Well got both sides installed finally just need to tighten everything up and look for 2 bolts i dropped. Driver side tool about 20 mins no issues. And halter i was thinking about wrapping the collectors but that was,about it. Might have to switch to angled sparkplug wires but not sure yet