6066 (1960-1966) GMC Truck Club Bitcoin now accepted here! 
Pay Dues
Pay Dues or become a Site Supporter
 



Go Back   6066 (1960-1966) GMC Truck Club > 6066 GMC Truck Club Forum > GMC V6 and V12 Engines


GMC V6 and V12 Engines Engine repair and rebuilding

Reply
 
Thread Tools
  #1  
Old October 28th, 2022, 02:02 AM
aztec aztec is offline
Junior Member
 
Join Date: Dec 2018
Location: Menomonie, wi
Truck: 1966
Age: 74
Posts: 3
Rep Power: 0
aztec is on a distinguished road
Default Exhaust Manifold

I need an exhaust manifold for a 351 V6 #2487598


Sent from my iPad using Tapatalk
Reply With Quote
  #2  
Old October 29th, 2022, 07:05 PM
sclor's Avatar
sclor sclor is online now
Senior Member
 
Join Date: Jan 2013
Location: New Orleans, LA
Truck: 1966 GMC 1000 series fenderside
Posts: 196
Rep Power: 114
sclor is on a distinguished road
Default Re: Exhaust Manifold

Aztec:
Which 351 do you have? 351e and 351m use larger port than 351c. 351c could therefore use 305 manifold.

If you have large port (magnum), I would check with the thunder v12 folks. The v12's they build are small port and they typically have large port that they would sell since they part out a lot of engines.

Hope that helps.
Regards
Steve
New Orleans b
Reply With Quote
  #3  
Old October 29th, 2022, 09:38 PM
aztec aztec is offline
Junior Member
 
Join Date: Dec 2018
Location: Menomonie, wi
Truck: 1966
Age: 74
Posts: 3
Rep Power: 0
aztec is on a distinguished road
Default Re: Exhaust Manifold

Thanks Steve,
Mine is a 351E
I will continue my search.


Sent from my iPad using Tapatalk
Reply With Quote
  #4  
Old October 29th, 2022, 09:52 PM
sclor's Avatar
sclor sclor is online now
Senior Member
 
Join Date: Jan 2013
Location: New Orleans, LA
Truck: 1966 GMC 1000 series fenderside
Posts: 196
Rep Power: 114
sclor is on a distinguished road
Default Re: Exhaust Manifold

351e is a large port magnum engine. The thunder v12 folks likely have some from my experience. Here is a link with contact info.

Regards
Steve
New Orleans

https://www.thunderv12.com/
Reply With Quote
  #5  
Old October 30th, 2022, 03:57 AM
aztec aztec is offline
Junior Member
 
Join Date: Dec 2018
Location: Menomonie, wi
Truck: 1966
Age: 74
Posts: 3
Rep Power: 0
aztec is on a distinguished road
Default Re: Exhaust Manifold

Thanks again


Sent from my iPad using Tapatalk
Reply With Quote
  #6  
Old October 30th, 2022, 07:22 AM
BobBray BobBray is offline
-= Dues Paid =-
 
Join Date: Feb 2013
Location: Los Angeles, CA.
Truck: 1967 CM 2500
Posts: 208
Rep Power: 118
BobBray will become famous soon enough
Default Re: Exhaust Manifold

The 351E uses a unique exhaust manifold. It does indeed have the large 'Magnum' ports but it also has the smaller 3 bolt pipe flange like a 305 or 351C. 351M's and other Magnum V-6's usually used the larger 'rib' style exhaust manifold with a large (@3") 3 bolt flange. The 351E exhaust manifold is a bit restrictive, you might not be that much worse off if you port-matched a 305 manifold as best you could. Then again, if you found a couple of 'real' Magnum exhaust manifolds and ran larger diameter exhaust pipes that would be even better than stock. BTW, there were 2 different 351E exhaust manifolds, one with air injection ports and one without.
Reply With Quote
  #7  
Old October 31st, 2022, 12:17 AM
lizziemeister'sV6 lizziemeister'sV6 is offline
-= Dues Paid =-
 
Join Date: Aug 2013
Location: Strawberry Point, Iowa
Truck: 1965 Suburban Series 1000 - 351M with mechancal tachometer - PS & PB & 2 speed Pow-R-Flow automatic
Age: 68
Posts: 184
Rep Power: 107
lizziemeister'sV6 is on a distinguished road
Default Re: Exhaust Manifold

Are the 3" manifolds you're talking about called "I Beams"? I have a pair and it looked like the exhaust pipe clamps to the manifold - these came from a 351 from a larger truck - I used a pair of 351E manifolds and yes - they constrict the exhaust down to the same lead pipe that the non-magnums use. Figured I would use the big I beams when the time comes to replace the pipes from the manifold to the "H pipe" I use.
Reply With Quote
  #8  
Old October 31st, 2022, 05:13 AM
BobBray BobBray is offline
-= Dues Paid =-
 
Join Date: Feb 2013
Location: Los Angeles, CA.
Truck: 1967 CM 2500
Posts: 208
Rep Power: 118
BobBray will become famous soon enough
Default Re: Exhaust Manifold

Quote:
Originally Posted by lizziemeister'sV6 View Post
Are the 3" manifolds you're talking about called "I Beams"? I have a pair and it looked like the exhaust pipe clamps to the manifold - these came from a 351 from a larger truck - I used a pair of 351E manifolds and yes - they constrict the exhaust down to the same lead pipe that the non-magnums use. Figured I would use the big I beams when the time comes to replace the pipes from the manifold to the "H pipe" I use.
Yes, the Magnum manifolds have ribs and are also called I-beam type. Some of the I-beam manifolds have large 3 bolt flanges, some have a flange for a V-band clamp. I think the clamp style are later years.
Reply With Quote
Reply

Bookmarks

Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Exhaust manifold Archiver Previous Forum Posts 3 May 12th, 2011 01:16 PM
Exhaust manifold coating Archiver Previous Forum Posts 0 March 4th, 2006 03:16 AM
Exhaust Manifold, Found it! Archiver Previous Forum Posts 0 July 11th, 2001 02:16 AM
Exhaust manifold Archiver Previous Forum Posts 0 July 9th, 2001 02:53 AM
Exhaust Manifold Archiver Previous Forum Posts 0 July 7th, 2001 02:20 AM


All times are GMT +1. The time now is 04:38 PM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2013, Jelsoft Enterprises Ltd 951670365209|1669304323|0
Feedback Buttons provided by Advanced Post Thanks / Like (Lite) - vBulletin Mods & Addons Copyright © 2022 DragonByte Technologies Ltd.