Dennis
Need Header Help
Thread Starter
Le Mans Master
Joined: Nov 2003
Posts: 5,771
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From: Maryland
St. Jude Donor '05, '09, '15
Need Header Help
I have a friend with a 67 coupe with factory side pipes. He has a GMPP 430 hp SB. The engine uses the GM fast burn aluminum heads. Now for the help question. He tried to have a set of Hedman side pipe headers installed. The shop said they will not fit. There appears to be a clearance problem around the steering box. We believe the problem comes from the heads. They have an extra thick deck and perhaps raised ports. We think this raises the exhaust ports which in turn raises the headers. Anyone ever heard of this? Recommendations/solutions?
Thanks
Tom
Thanks
Tom
Thread Starter
Le Mans Master
Joined: Nov 2003
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From: Maryland
St. Jude Donor '05, '09, '15
Safety Car
Joined: May 2003
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From: Ocean Township NJ
It's doable but not easy. Remove the flanges from the old headers and replace with D port flanges. Tack weld them to the primaries. Heat and expand the primaries, shape them and weld inside and out to the new flanges. File the mating surfaces flat. Dress the insides of the runners where they meet the headers with a bur on a die grinder.
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Thread Starter
Le Mans Master
Joined: Nov 2003
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From: Maryland
St. Jude Donor '05, '09, '15
http://www.stahlheaders.com/Frame%20New%20Drag.htm
Tom
Drifting
Joined: Jul 2004
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From: Wi
I have a friend with a 67 coupe with factory side pipes. He has a GMPP 430 hp SB. The engine uses the GM fast burn aluminum heads. Now for the help question. He tried to have a set of Hedman side pipe headers installed. The shop said they will not fit. There appears to be a clearance problem around the steering box. We believe the problem comes from the heads. They have an extra thick deck and perhaps raised ports. We think this raises the exhaust ports which in turn raises the headers. Anyone ever heard of this? Recommendations/solutions?
Thanks
Tom
Thanks
Tom
Thread Starter
Le Mans Master
Joined: Nov 2003
Posts: 5,771
Likes: 694
From: Maryland
St. Jude Donor '05, '09, '15
Tom
Thread Starter
Le Mans Master
Joined: Nov 2003
Posts: 5,771
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From: Maryland
St. Jude Donor '05, '09, '15
Tom
Race Director
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From: Clayton NC
Thread Starter
Le Mans Master
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From: Maryland
St. Jude Donor '05, '09, '15
Race Director
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From: Clayton NC
Race Director
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From: Del Boca Vista FL
Hey Tom:
I ran into the same thing on my 63 with the Heddman headers only the clearance problem was on the pasenger side and I had to shorten the threaded section if the idler arm. I was using Canfield heads, angle plug and raised exhaust ports. Should have ordered the Heddman headers for angle plug heads. Was a big PITA to change plugs. Loosen with open end wrench and remove as socket would not fit on at least four of the plugs due to tube interference. With the angle plug headers they change position of the center tubes from inside to outside or reverse. I don't recall right now.
An option would be to purchase an angled spacer plate to go between the head and the header flange or purchase straight spacer plates and have them machined to the preferred angle.
Rich
I ran into the same thing on my 63 with the Heddman headers only the clearance problem was on the pasenger side and I had to shorten the threaded section if the idler arm. I was using Canfield heads, angle plug and raised exhaust ports. Should have ordered the Heddman headers for angle plug heads. Was a big PITA to change plugs. Loosen with open end wrench and remove as socket would not fit on at least four of the plugs due to tube interference. With the angle plug headers they change position of the center tubes from inside to outside or reverse. I don't recall right now.
An option would be to purchase an angled spacer plate to go between the head and the header flange or purchase straight spacer plates and have them machined to the preferred angle.
Rich
Thread Starter
Le Mans Master
Joined: Nov 2003
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From: Maryland
St. Jude Donor '05, '09, '15
Hey rich. I forgot you used hedmans.
I didn't know they made special angle plug headers. I'll look into that. The shop sent the headers back when they didn't clear so new ones would be doable. You have the borgeson box. That may make a difference on the drivers side.
I'll call you later
Tom
I didn't know they made special angle plug headers. I'll look into that. The shop sent the headers back when they didn't clear so new ones would be doable. You have the borgeson box. That may make a difference on the drivers side.
I'll call you later
Tom
Thread Starter
Le Mans Master
Joined: Nov 2003
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From: Maryland
St. Jude Donor '05, '09, '15