how big of bore gen 5 bbc

Old 03-18-2008, 06:24 PM
  #1  
randybryan
Junior Member
SHOW GUEST
Thread Starter
 
Join Date: Mar 2003
Posts: 2
Default how big of bore gen 5 bbc

I have a bbc marine, gen 5, 4 bolt block. Going to freshen. Thinking about a new rotating assembly. How big can you bore this block and still be reliable. It's a bracket/index motor. Dont want to fill block.
randybryan is offline  
Old 03-18-2008, 07:36 PM
  #2  
68bbnova
Member
MASTER JOURNEYMAN
 
Join Date: Nov 2003
Location: Newark, Delaware
Posts: 46
Default

454 or 502?
68bbnova is offline  
Old 03-18-2008, 09:11 PM
  #3  
OneBadGMC
Senior Member
RACING JUNKIE
 
Join Date: Sep 2007
Location: Belleville, IL
Posts: 658
Default

If you're worried about reliability, don't go more than .060 over. Put a 4-1/4" crank in it and be done.
OneBadGMC is offline  
Old 03-19-2008, 03:31 AM
  #4  
hink
Senior Member
EXPERT BUILDER
 
Join Date: Nov 2003
Location: NORTHEAST
Posts: 290
Default

A soinic test would be the way to go!!!!!!
hink is offline  
Old 03-21-2008, 07:42 PM
  #5  
randybryan
Junior Member
SHOW GUEST
Thread Starter
 
Join Date: Mar 2003
Posts: 2
Default 454

it is a 454 block
randybryan is offline  
Old 03-21-2008, 10:48 PM
  #6  
cepx111
Senior Member
RACING JUNKIE
 
Join Date: May 2006
Posts: 2,044
Default

Originally Posted by OneBadGMC
If you're worried about reliability, don't go more than .060 over. Put a 4-1/4" crank in it and be done.
DITTO!
cepx111 is offline  
Old 04-04-2008, 10:03 AM
  #7  
TopspeedLowet
Senior Member
DYNO OPERATOR
 
Join Date: Apr 2008
Posts: 504
Default Re: how big of bore gen 5 bbc

Originally Posted by randybryan
I have a bbc marine, gen 5, 4 bolt block. Going to freshen. Thinking about a new rotating assembly. How big can you bore this block and still be reliable. It's a bracket/index motor. Dont want to fill block.
I have been using a bow tie gen v block bored to 4.600 using 15 to one comp. and have no grout in the block. The GM max recomended bore for this block is 4.6". Grout is for bone stock blocks with core shift. A new aftermarket block is cheep insurance for block quality. You'll have more in machine work and gimicks to get the durability of a good block than a good block costs. You decide
TopspeedLowet is offline  
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


Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service - Do Not Sell My Personal Information -