5.3L c/r not adding up - LS1TECH - Camaro and Firebird Forum Discussion



New LS1 Owners - Newbie Tech Basic Technical Questions & Advice
Sponsored by:
Sponsored by:

5.3L c/r not adding up

Reply
 
Thread Tools Search this Thread
Old 03-02-2017, 10:17 AM   #1
On The Tree
Thread Starter
 
Join Date: Mar 2017
Posts: 162
Default 5.3L c/r not adding up

Im new to LS engines amd am planning a build very soon. But nothing is adding up. Where am i getting my math wrong on engine compression.
5.3L LM7 with 862 stock heads
Bore: 3.78
Stroke: 3.62
Cylinders: 8
Pistion cc: 2cc
Head cc: 61cc
Head gasket: .040
Pistion Height: .007

Everything is telling me crazy **** like 10.7:1 when known ratio is 9.5:1
OxTheGreat is offline   Reply With Quote
Old 03-02-2017, 11:05 AM   #2
On The Tree
Thread Starter
 
Join Date: Mar 2017
Posts: 162
Default

After doing some tinkering on here and plugging away at numbers i suppose my pistons are the 9cc dishes rather than the 2cc flat tops.
OxTheGreat is offline   Reply With Quote
Old 03-02-2017, 12:32 PM   #3
Restricted User
 
Join Date: Mar 2014
Location: Ohio
Posts: 4,550
Default

Stock engine?

You would have dished pistons, and a .051" headgasket most likely.
JoeNova is offline   Reply With Quote
Old 03-02-2017, 01:05 PM   #4
On The Tree
Thread Starter
 
Join Date: Mar 2017
Posts: 162
Default

Quote:
Originally Posted by JoeNova View Post
Stock engine?

You would have dished pistons, and a .051" headgasket most likely.
Yes, 100% stock, im mapping out a JY build like many.
OxTheGreat is offline   Reply With Quote
Old 03-02-2017, 07:52 PM   #5
12 Second Club
iTrader: (2)
 
murphinator's Avatar
 
Join Date: Sep 2009
Location: southern Maine
Posts: 1,637
Default

flat top 4.8/5.3 stamped blocks are 4.8's so you should have the dished.
murphinator is offline   Reply With Quote
Reply

Related Topics
Thread Thread Starter Forum Replies Last Post
Build plans so far OxTheGreat Generation III Internal Engine 8 03-08-2017 07:50 PM
Do i need a new tune after rebuid? 6.0avalanche New LS1 Owners - Newbie Tech 4 10-16-2016 07:46 PM
Mounting procharger to 4.8 or 5.3 block? sweet99ss Forced Induction 9 04-06-2013 02:39 PM
How much power 383 LT12TRI LT1-LT4 Modifications 1 11-17-2005 10:01 PM


Thread Tools Search this Thread
Search this Thread:

Advanced Search

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
Trackbacks are Off
Pingbacks are Off
Refbacks are Off



All times are GMT -5. The time now is 09:46 PM.


 
  • Ask a Question
    Get answers from community experts
Question Title:
Description:
Your question will be posted in: