Sweet!
New headers for C-4's
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Joined: Dec 2010
Posts: 64
Likes: 0
From: Orange So Cal
May I suggest a 3 bolt flange alternative? I think most of the years are 3 bolts and it probably is a better sealing design. It would be a shame to buy a brand new Y-pipe with no cats and have to hack it up to put a different flange on it and create another possible leak point.
the flange to be a two bolt for clearance.
As far as the sealing, the ball and socket connection requires no gasket
and is the best connection there is.
Even with a new y-pipe it would have to have the end shortened at the 90* where it connects.
The whole idea is to make a better transition for the four tubes instead of crushing them in to fit the stock flange (defeating the purpose of headers). One cut, one weld, that is as simple as I can make it.
Drifting
Joined: Oct 2006
Posts: 1,328
Likes: 14
From: Stafford Connecticut
You can take your y pipe to any muffler shop and they would cut and weld it for $50 tops.I have taken muffler parts to muffler shops to be modified many times over the years and they have always been very willing to help out us hot rodders.
Le Mans Master
Joined: Oct 2008
Posts: 9,758
Likes: 49
From: Houston Texas
I had my last y pipe welded for $30.
Instructor
Joined: Apr 2011
Posts: 218
Likes: 16
From: Littleton CO
Because of the better design on the collector ( a little lower) it requires
the flange to be a two bolt for clearance.
As far as the sealing, the ball and socket connection requires no gasket
and is the best connection there is.
Even with a new y-pipe it would have to have the end shortened at the 90* where it connects.
The whole idea is to make a better transition for the four tubes instead of crushing them in to fit the stock flange (defeating the purpose of headers). One cut, one weld, that is as simple as I can make it.
the flange to be a two bolt for clearance.
As far as the sealing, the ball and socket connection requires no gasket
and is the best connection there is.
Even with a new y-pipe it would have to have the end shortened at the 90* where it connects.
The whole idea is to make a better transition for the four tubes instead of crushing them in to fit the stock flange (defeating the purpose of headers). One cut, one weld, that is as simple as I can make it.
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Drifting
Joined: Dec 2007
Posts: 1,647
Likes: 4
From: Argillite KY
Hey Don, I don't have any measuring tool for the thread size but it looks like OBX welded a stainless 1/2" pipe coupling on theirs. My spare outside faucet (1/2 NPT) screws into it perfectly so I'd say 1/2 NPT.
Those hillbilly measuring tools seem to work.
Those hillbilly measuring tools seem to work.
Thread Starter
Racer
Joined: Jun 2006
Posts: 361
Likes: 6
There was some question about straight plug clearance so here's some pics. With standard length plugs there is approximately 3/4" clearance from the tubes on plugs 1 & 8, and a little over 1" on the rest. I installed the boots without having to touch the tubes.
