#1  
Old 08-18-2019, 04:04 PM
elefantrider's Avatar
elefantrider elefantrider is offline
Ultimate Warrior
 
Join Date: May 2004
Location: So. California
Posts: 2,293
Default '63 Tempest 326 V8 maximum overbore?

What is the max overbore on an original '63 326 TEMPEST one-year-only block?

  #2  
Old 08-19-2019, 11:19 AM
elefantrider's Avatar
elefantrider elefantrider is offline
Ultimate Warrior
 
Join Date: May 2004
Location: So. California
Posts: 2,293
Default

Can it be sleeved to 4.062 ( std 389 bore)?

  #3  
Old 08-19-2019, 11:47 AM
mechanickeith's Avatar
mechanickeith mechanickeith is offline
Ultimate Warrior
 
Join Date: Dec 2002
Location: Phoenix, Az
Posts: 5,812
Default

You would have to get it sonic checked. I don't know much about the 326's. I have several 4 bangers that are at .120 over bore.

__________________
Keith Collier
61-63 Pontiac Tempest
Tech advisor
POCI.org
  #4  
Old 08-19-2019, 12:39 PM
tom s tom s is offline
Ultimate Warrior
 
Join Date: Jan 2000
Location: long beach ca usa
Posts: 18,764
Default

I don’t think you want all 8 sleeves anyway

  #5  
Old 08-19-2019, 12:57 PM
Bill Hanlon's Avatar
Bill Hanlon Bill Hanlon is offline
Ultimate Warrior
 
Join Date: Feb 2005
Location: Fredericksburg, TX
Posts: 2,349
Default

According to the 1966 Pontiac Chassis Parts Catalog, Pontiac only supplied oversize pistons for the '63 326 (actually 336) to +0.030" = 3.810". Not saying you couldn't find larger pistons elsewhere.

__________________
My Pontiac is a '57 GMC with its original 347" Pontiac V8 and dual-range Hydra-Matic.
  #6  
Old 08-19-2019, 04:30 PM
ponyakr's Avatar
ponyakr ponyakr is offline
Ultimate Warrior
 
Join Date: Dec 2011
Location: North Louisiana
Posts: 7,621
Default

"You would have to get it sonic checked..."

^^^^^^^^^THIS^^^^^^^^^^^^

No matter what block you use, you must know how much meat you'll have left, after required bore/hone. Core shift & years of corrosion can reduce cylinder wall thickness on any given cylinder.

  #7  
Old 08-19-2019, 10:03 PM
beemergary's Avatar
beemergary beemergary is offline
Ultimate Warrior
 
Join Date: Mar 2003
Posts: 1,386
Default

Quote:
Originally Posted by ponyakr View Post
"You would have to get it sonic checked..."

^^^^^^^^^THIS^^^^^^^^^^^^

No matter what block you use, you must know how much meat you'll have left, after required bore/hone. Core shift & years of corrosion can reduce cylinder wall thickness on any given cylinder.
I know of a 326 at .090 overbore. My 421 is .070

  #8  
Old 10-29-2019, 08:48 PM
63Banshee's Avatar
63Banshee 63Banshee is offline
Ultimate Warrior
 
Join Date: Oct 2001
Location: D/FW, TX
Posts: 2,901
Default

Had one with 350 pistons. That's .094 over.

Reply

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 10:51 AM.

 

About Us

The PY Online Forums is the largest online gathering of Pontiac enthusiasts anywhere in the world. Founded in 1991, it was also the first online forum for people to gather and talk about their Pontiacs. Since then, it has become the mecca of Pontiac technical data and knowledge that no other place can surpass.

 




Copyright © 2017