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Re: [GMCnet] Weekend DIY Header [message #162345] Tue, 06 March 2012 13:01 Go to next message
Richard Brown is currently offline  Richard Brown   United States
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Registered: May 2009
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I have a question. I noticed a set of headers online while looking up a set for a neighbor of mine for a Mustang that were called "Tri-Y". They were a 4-2-1 style header for tight spaces. Not real sure how they work, but I have been told that they di work better than stock. Has anyone researched wheather that style of header would work for a GMC? Seems to me that if someone could come up with something that could be installed without the need to re-do the headpipes too much would be a good thing. Sort of a direct replacement for cast iron manifolds. Just wondering if this has been tried or not...

Richard & Carol Brown

1974 Eleganza SE

"DILLIGAF"

Lindale, Tx. 75771

903-881-0192
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Richard & Carol Brown 1974 Eleganza SE 1174 Hickory Hills Dr. Murchison, TX. 75778
Re: [GMCnet] Weekend DIY Header [message #162348 is a reply to message #162345] Tue, 06 March 2012 16:32 Go to previous messageGo to next message
John Heslinga   Canada
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Registered: February 2011
Location: Edmonton, Alberta, Canada
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Hi Richard:

The Doug Thorley header that Applied GMC sells is a tri-Y header. As you saw in your research, Tri-Y headers are good for lower RPM applications. As each pulse of exhaust flow goes through a leg of the Y, it creates a slight vacuum in the other leg. The timing or pairing of the Ys is important to the flow gains.

Edited a few mins later:
The final collector on the headers line up with the mufflers eliminating the need for the head pipe. I just installed a set and really happy with the result (I have not uploaded pictures just yet)


Best regards


John and Cathie Heslinga 1974 Canyonlands 260 455, Manny tranny and 1 ton, 3:70 LS, Red Seal Journeyman, DTE, BEd. MEd. Edmonton, Alberta

[Updated on: Tue, 06 March 2012 16:36]

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Re: [GMCnet] Weekend DIY Header [message #162350 is a reply to message #162345] Tue, 06 March 2012 17:25 Go to previous messageGo to next message
John Heslinga   Canada
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Registered: February 2011
Location: Edmonton, Alberta, Canada
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Picture of the Doug Thorley Tri-Y header on my new engine uploaded.

http://www.gmcmhphotos.com/photos/showphoto.php?photo=43092&title=tri-y-header&cat=500



John and Cathie Heslinga 1974 Canyonlands 260 455, Manny tranny and 1 ton, 3:70 LS, Red Seal Journeyman, DTE, BEd. MEd. Edmonton, Alberta
Re: [GMCnet] Weekend DIY Header [message #162352 is a reply to message #162345] Tue, 06 March 2012 17:39 Go to previous message
bwevers is currently offline  bwevers   United States
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Registered: October 2010
Location: San Jose
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It Looks Sweet!

Regards,
Bill


Bill Wevers GMC49ers, GMC Western States 1975 Glenbrook - Manny Powerdrive, OneTon 455 F Block, G heads San Jose
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