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
  #21  
Old February 5th, 2018, 10:06 PM
Otto68 Otto68 is offline
Junior Member
 
Join Date: Jul 2015
Location: Williamsport,PA
Truck: 1968
Age: 40
Posts: 21
Rep Power: 27
Otto68 is on a distinguished road
Default Re: Head gaskets 351

Let me explain what I meant by the 4.56 bore. All 351 and 702 engins share the same head gasket about 99% posative on that. But im not shore if it is the same as the 379 head gasket.
Reply With Quote
  #22  
Old February 5th, 2018, 10:24 PM
jrmunn jrmunn is offline
Senior Member
 
Join Date: Feb 2013
Location: Davis, California
Truck: 1964 1500
Posts: 118
Rep Power: 66
jrmunn is on a distinguished road
Default Re: Head gaskets 351

Otto68,

Thank you for such a quick reply. It sounds like I should figure this out now so that at least the gaskets part of putting things back together can be taken care of before taking the engine apart. I have an old Victor gasket kit that says it fits 1960-64 351 (and 401?) V6 engines, which should be good for most of the gaskets, except for intake and exhaust, now that I know more about what fits the heads.

JRMunn
Reply With Quote
  #23  
Old February 6th, 2018, 01:35 AM
bigblockv6 bigblockv6 is offline
-= Dues Paid =-
 
Join Date: Jan 2013
Location: Rohnert Park, ca.
Truck: 1968 KM2500
Posts: 1,225
Rep Power: 349
bigblockv6 will become famous soon enough
Default Re: Head gaskets 351

Quote:
Originally Posted by jrmunn View Post
Otto68,

Thank you for such a quick reply. It sounds like I should figure this out now so that at least the gaskets part of putting things back together can be taken care of before taking the engine apart. I have an old Victor gasket kit that says it fits 1960-64 351 (and 401?) V6 engines, which should be good for most of the gaskets, except for intake and exhaust, now that I know more about what fits the heads.

JRMunn
I've seen that before too where it calls for the 351 to use the 401 head gasket. As far as the 379 it shares the exact same bore as the 351 so there should be no reason that you couldn't use 379 head gasket on a 351 if you came across them, same goes for using 432 head gaskets on a 401 engine, In fact I have an engine gasket set I bought for a 401M that I may build in the future and the engine gasket set lists it's for both 401 and 432 engines.
Reply With Quote
  #24  
Old February 6th, 2018, 04:34 AM
Otto68 Otto68 is offline
Junior Member
 
Join Date: Jul 2015
Location: Williamsport,PA
Truck: 1968
Age: 40
Posts: 21
Rep Power: 27
Otto68 is on a distinguished road
Default Re: Head gaskets 351

Sounds like you are in better shape than I am Jrmunn.

The 401 and 432 do use the same as the 351, I wasn't positive about that since they have a bigger bore. That's good to know.

On a side note, I got a call back from Molina and will be shipping them a head gasket in the morning. They said they could do a stock style gasket from around 30,000 thickness and up. They could do a Felpro style gasket too if money was a problem.
Reply With Quote
  #25  
Old February 6th, 2018, 04:47 AM
bigblockv6 bigblockv6 is offline
-= Dues Paid =-
 
Join Date: Jan 2013
Location: Rohnert Park, ca.
Truck: 1968 KM2500
Posts: 1,225
Rep Power: 349
bigblockv6 will become famous soon enough
Default Re: Head gaskets 351

I had a 351 head gasket that I compared to a 401 and it definitely had a smaller bore opening though it is said you can use 401 head gaskets on the 351. Not to change the subject but I have done several cylinder head conversion on the Jeep 4.2(258 ci) inline six to the 4.0 cylinder head and the proper head gasket to use is the 4.0 which unlike the long stroke 4.2 has a considerably larger bore. So evidently it's ok to use a head gasket meant for a bigger bore engine within certain parameters.
Reply With Quote
  #26  
Old February 6th, 2018, 04:01 PM
Otto68 Otto68 is offline
Junior Member
 
Join Date: Jul 2015
Location: Williamsport,PA
Truck: 1968
Age: 40
Posts: 21
Rep Power: 27
Otto68 is on a distinguished road
Default Re: Head gaskets 351

That I can understand because of the gasket not being in the chamber opening. It could possibly be better since the edge of the gasket would be further away from the combustion and less likely to burn out. It's almost like putting a 351 head om a 305. you have to use the 351 head gasket because of the larger chamber in the head. The 305 gasket would be inside the chamber not recessed like it should be. I know this because of thats what I'm doing now. I started building the 305 and a 351E fell into my lap. I already had 30 over pistons and the block started. didn't want to throw the money away. You never get out of it what you put into it. Don't know what I'm doing with the block but if I build it the way I'm thinking It's going to cost a lot. Custom 8.2" rod, 1.45 compression height piston, and an offset grind on the crank to bring the bearing down to 2.5 and get a .15 longer stroke.
Reply With Quote
  #27  
Old February 11th, 2018, 01:18 AM
bigblockv6 bigblockv6 is offline
-= Dues Paid =-
 
Join Date: Jan 2013
Location: Rohnert Park, ca.
Truck: 1968 KM2500
Posts: 1,225
Rep Power: 349
bigblockv6 will become famous soon enough
Default Re: Head gaskets 351

I figured I post some pics of both the 351 and 401 head gaskets for comparison, in the pic with the two gaskets side by side the one on the bottom is an OEM 351 head gasket(with "Victor" stamped on it) and on the top is a 401 gasket. You can see how the 351 gasket has oblong holes in order to make clearance for the valves to go through. The other pic shows the 401 gasket on top of the 351 gasket
Attached Images
File Type: jpg 20180210_153527 (1).jpg (7.70 MB, Multiple views, 13 clicks)
File Type: jpg 20180210_153558.jpg (7.39 MB, Multiple views, 13 clicks)
Reply With Quote
  #28  
Old March 3rd, 2018, 03:17 PM
Otto68 Otto68 is offline
Junior Member
 
Join Date: Jul 2015
Location: Williamsport,PA
Truck: 1968
Age: 40
Posts: 21
Rep Power: 27
Otto68 is on a distinguished road
Default Re: Head gaskets 351

So after the gasket getting lost in shipping and Molina Gaskets getting to look at it, I got some prices for the 351 head gasket. For the Felpro style with copper rings, it will be 152 a head or 304 a set. The gasket that is a direct replacement for the original will be 180 a head or 360 a set. So the best price is solid copper form Cometic gaskets at 233 a set.
Reply With Quote
  #29  
Old March 3rd, 2018, 08:54 PM
schwoch1 schwoch1 is offline
Junior Member
 
Join Date: Apr 2017
Location: Burlington, WI
Truck: 1967 GMC C20
Age: 42
Posts: 1
Rep Power: 0
schwoch1 is on a distinguished road
Default Re: Head gaskets 351

Have you considered contacting http://www.gasketstogo.com/. I know they are overseas, but apparently the guy that runs the place is american. I know a few of my customers have used them in the past for oddball gaskets and had no complaints! It looks as if they can do MLS style gaskets also!

Maybe they can help, maybe they can't! Worth a shot!!!

Mike
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
Head Gaskets Quigley 1960-1966 GMC Marketplace 3 May 9th, 2018 03:19 AM
Head Gaskets Quigley GMC V6 and V12 Engines 0 November 5th, 2017 06:51 PM
351 head gaskets? bobdylan 1960-1966 GMC Marketplace 0 May 17th, 2016 02:52 PM
head gaskets? 66birdman GMC V6 and V12 Engines 0 March 12th, 2014 01:37 PM
Where to buy Head Gaskets? Archiver Previous Forum Posts 6 September 27th, 2012 03:54 PM


All times are GMT +1. The time now is 01:44 PM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2013, Jelsoft Enterprises Ltd 117|0
Feedback Buttons provided by Advanced Post Thanks / Like (Lite) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.