Header question

LQQKatJon

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Oct 22, 2010
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helping someone work on a GMC. and we have run into a little snag. I apologize as I do not have photos yet of our problem, as the gmc is about an hour away from me right now.

New engine to exhaust hook up is not lining up on passenger side. My question is header identificaiton? is there any information how to identify if you have Thorley headers, or Doug headers.

I will probably call JimK once I get my eyes on the total problem.. I see he has:

that is noted for doug header, and not the "old thorley" headers. so I am curious what I need to look for to tell the difference.
 
I've had what I understood to be "Doug Thorley" headers in both of my coaches. I don't know what era they're from. I've never heard of a distinction between Doug headers or Thorley headers, so now I'm curious what this is about.
 
I've had what I understood to be "Doug Thorley" headers in both of my coaches. I don't know what era they're from. I've never heard of a distinction between Doug headers or Thorley headers, so now I'm curious what this is about.

Doug Thorley, and their patterns were purchased by Summit Racing/Atech a whole back. Brain says about a decade ago, but I have learned not to trust it for stuff like that.

They carried the "Thorley" name for a while, then as most of the old school jot rodders passed, and their tri-y technology wasn't remembered, they just started calling themselves Doug's.

Same company (though made overseas now), same patterns, I've had good luck with their headers, even post Summit acquisition. I have a brand new set for the coach in a box, run the LS-Swap headers on my C10. Ran a set on my Corvette for a while.

Call their tech line that should be in the box, with photos and an explanation. They'll be happy to help, I'm sure. If you need the number/tossed the paperwork, let me know. I'll be happy to go dig it out of my box.
 
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I've had what I understood to be "Doug Thorley" headers in both of my coaches. I don't know what era they're from. I've never heard of a distinction between Doug headers or Thorley headers, so now I'm curious what this is about.
Found this:
Doug's Headers and Doug Thorley DO have a business connection.
Doug and wife Betty sold the original 50's version of the company (Headers by Doug) and got
divorced and the new owner Micky then called it Doug Thorley Headers.
Micky's health went downhill and he asked Betty to come back and help him run the company.
Doug came back onboard to do R&D. Eventually there was another falling out between Doug &
Betty and Doug left to do his own startup..... under the "Doug's Headers" name.
Nowadays, Doug's Headers is owned by Pertronix and Doug Thorley is owned by Summit Industries
in Corona CA. (no connection to Summit Racing) Summit Ind also owns Jardine Headers.
 
Found this:
Doug's Headers and Doug Thorley DO have a business connection.
Doug and wife Betty sold the original 50's version of the company (Headers by Doug) and got
divorced and the new owner Micky then called it Doug Thorley Headers.
Micky's health went downhill and he asked Betty to come back and help him run the company.
Doug came back onboard to do R&D. Eventually there was another falling out between Doug &
Betty and Doug left to do his own startup..... under the "Doug's Headers" name.
Nowadays, Doug's Headers is owned by Pertronix and Doug Thorley is owned by Summit Industries
in Corona CA. (no connection to Summit Racing) Summit Ind also owns Jardine Headers.
Alright...

The story I got from the Atech guys was wrong... Believe this, not mine. :)

I have Jardines on my Impala. Small world on vintage performance parts.
 
helping someone work on a GMC. and we have run into a little snag. I apologize as I do not have photos yet of our problem, as the gmc is about an hour away from me right now.

New engine to exhaust hook up is not lining up on passenger side. My question is header identificaiton? is there any information how to identify if you have Thorley headers, or Doug headers.

I will probably call JimK once I get my eyes on the total problem.. I see he has:

that is noted for doug header, and not the "old thorley" headers. so I am curious what I need to look for to tell the difference.
LQQK they should be marked. at least mine are ( drivers side ) larry
 

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