Converting SBC External Balance to Internal Balance - Hot Rod Forum : Hotrodders Bulletin Board
Hotrodders.com -- Hot Rod Forum



Register FAQ Search Today's Posts Unanswered Posts Auto Escrow Insurance Auto Loans
Hot Rod Forum : Hotrodders Bulletin Board > Tech Help> Engine
User Name
Password
lost password?   |   register now

Reply
 
LinkBack Thread Tools
  #1 (permalink)  
Old 02-18-2010, 12:24 PM
zildjian4life218's Avatar
Listen and Learn
 
Last wiki edit: DIY junkyard electrical fan controller
Last journal entry: SBC 305 Twin Turbo
Last photo:
Join Date: Dec 2008
Location: WNY/Rochester, New York
Age: 25
Posts: 1,642
Wiki Edits: 7

Thanks: 44
Thanked 8 Times in 8 Posts
Converting SBC External Balance to Internal Balance

The other day I was going through the price sheets for my recent build sbc 350 and came across the one from the machine shop. He wrote down internal balanced. The crank and block are a 1pc from a 1991 pickup which i believe are from the factory externally balanced.

I wanted to make sure he balanced it correctly i called him up and he said the balance was almost dead on, it was indeed internal and he only charged me $100. I reused the stock crank it was ground .010 on the mains and rods. Eagle I beam rods and Keith black flat top hyp pistons. Speed pro rings. I am running a neutral balance flexplate because the motor had a flywheel on it when i got it.

So my question is can an externally balanced rotating assembly be converted to internally balanced by running a neutral flexplate and very little balancing.

    Advertisement
Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
  #2 (permalink)  
Old 02-18-2010, 12:35 PM
bondo's Avatar
Member
 
Last photo:
Join Date: Nov 2002
Location: Chaumont Bay N.Y.
Posts: 960
Wiki Edits: 0

Thanks: 7
Thanked 15 Times in 15 Posts
Quote:
which i believe are from the factory externally balanced.
Nope,... Your motor is known as an Internally balanced motor....

Only the old 400 SBC were Externally balanced....
Reply With Quote Quick reply to this message
  #3 (permalink)  
Old 02-18-2010, 12:42 PM
Registered User
 
Last photo:
Join Date: Nov 2009
Location: no longer here
Posts: 293
Wiki Edits: 0

Thanks: 0
Thanked 2 Times in 2 Posts
SBC is internally balanced

but to answer can a externally balanced motor be change to internal by going to a nuetral flywheel/flexplate and very little mallory metal added to the inside , No its going totake alot of mallory metal to be added it mostly depends on what your bob weights add up to be , but you will net to change to th nuetral flexplate/flywheel and a nuetral dampner to make it internally balanced , easiest way to identify a external balanced motor is look at the backside of the dampner theres either going to be a cutout on one side or a bunch of metal offset to oneside by the hub ( and certain fords they actually have bobweights that slide on the crankshaft )
Reply With Quote Quick reply to this message
  #4 (permalink)  
Old 02-18-2010, 01:02 PM
Blazin72's Avatar
You got a leaky spark tube...
 
Last wiki edit: Rearend removal
Last journal entry: General Lee
Last photo:
Join Date: Jul 2005
Location: Union, WA
Age: 32
Posts: 2,868
Wiki Edits: 19

Thanks: 0
Thanked 2 Times in 2 Posts
I believe the 1 piece seal engines use a neutral balance damper up front and an externally balanced flywheel/flexplate at the rear because of the different style crank flange.
Reply With Quote Quick reply to this message

Recent Engine posts with photos

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the Hot Rod Forum : Hotrodders Bulletin Board forums, you must first register.
Please enter your desired user name (usually not your first and last name), your email address and other required details in the form below.
User Name:
If you do not want to register, fill this field only and the name will be used as user name for your post.
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.




Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools

Posting Rules
You may post new threads
You may 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
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
Problem converting a 1972 Camaro to an internal regulator raglandk Electrical 0 10-11-2008 03:10 PM
Internal vs External Balance 614streets Engine 3 05-28-2003 01:25 PM
Internal or external balanced engine reclusej Engine 4 01-22-2003 05:27 PM
460 external or internal thames Engine 9 10-08-2002 02:12 PM
Internal vs External dollybud Electrical 4 08-05-2002 06:48 PM


All times are GMT -6. The time now is 11:27 PM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0 PL2
Copyright Hotrodders.com 1999 - 2012. All Rights Reserved.