The 1947 - Present Chevrolet & GMC Truck Message Board Network







Register or Log In To remove these advertisements.

Go Back   The 1947 - Present Chevrolet & GMC Truck Message Board Network > 47 - Current classic GM Trucks > The 1967 - 1972 Chevrolet & GMC Pickups Message Board

Web 67-72chevytrucks.com


Reply
 
Thread Tools Display Modes
Old 07-24-2016, 10:33 PM   #1
Brads72Build
Registered User
 
Join Date: Jul 2016
Location: Colorado
Posts: 2
1972 CMC 3/4 ton 4x4 SB to BB Question

I am rehabbing a 1972 GMC and am going from a 350 to a Big Block. In my research, I have found all kinds of conflicting info about the engine mount stands that bolt to the frame rails and the cross member. Will the stands for the factory 350 work for me at all, or is it just a mater of moving the locations,,,,, or finding BB mounts? I hope I have followed the right protocol on this, as I am new here. Any help from the experts on here is appreciated.

Thanks,
Brads72Build is offline   Reply With Quote
Old 07-25-2016, 11:33 AM   #2
Livrat
Member #1049
 
Livrat's Avatar
 
Join Date: Jun 2000
Location: Troy Montana
Posts: 3,940
Re: 1972 CMC 3/4 ton 4x4 SB to BB Question

The factory 350 crossmember/engine mount work fine (there are no factory big block mounts for a 4X4). The only issues is you will need to either modify the firewall to clear the valve covers and HEI. use a body lift to make the valve covers fit.. OR move it all forward approx 2-3" inches. If you move it forward a small block 2WD fan shroud works perfectly, the only downside is you have to shorten the front drive shaft, and have a new rear one made, Another way (assuming your truck is an Automatic) is to move the engine and mounts forward, use a 700R4 trans (which is a couple inches longer than a T350) coupled to the NP205, then all the other drive train stays in its original spot.
Livrat is offline   Reply With Quote
Old 07-25-2016, 03:07 PM   #3
Brads72Build
Registered User
 
Join Date: Jul 2016
Location: Colorado
Posts: 2
Re: 1972 CMC 3/4 ton 4x4 SB to BB Question

Livrat, thanks for the info, it is appreciated. I have rebuilt the 205 and have built and installed a 4L60E transmission in it with all the driveshaft work completed,,,,, so when get the body work completed, I will go to work on either the fire wall, or a body lift if needed. When installing the new transmission we did move things forward about an inch and half, so I might not have much to do. I still have a 68 stepside that I built years ago, which I took from a straight 6 to a BB, but I have gotten a little rusty on all that I did several years ago. Thanks again, for the helpful advice.
Brads72Build is offline   Reply With Quote
Reply

Bookmarks

Thread Tools
Display Modes

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

Forum Jump


All times are GMT -4. The time now is 10:52 PM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
Copyright 1997-2022 67-72chevytrucks.com