New heads need piston/compression recommendation - 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 12-12-2010, 10:03 PM
Registered User
 
Join Date: Jan 2009
Location: Orlando
Posts: 344
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
New heads need piston/compression recommendation

Just purchased a set of trickflow heads and wanted to know if I should be shooting for 9:5 or 10:1 compression. I will figure out cam a little later, but in search of a piston and compression to start. I know with alum heads you can run one more full point compression. I read an article where someone built a 9:3 compression motor that made close to 400 hp with these same trickflow heads. The article stated that the car will be ran on 91 octane, but with the compression being lower (below 9:5) it could possibly even run well on 87 octane. What seems to be the threshold for these heads and street driving. I believe too low can hurt too as well as having too much compression.

My question is what should I be shooting for for compression. This will be a pretty much stock 306 other than the TFS 170 heads.
.
Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
  #2 (permalink)  
Old 12-12-2010, 10:31 PM
Greg T's Avatar
www.krusinklassics.net
 
Last photo:
Join Date: Jul 2007
Location: Escanaba, MI.
Age: 60
Posts: 1,075
Wiki Edits: 0

Thanks: 7
Thanked 32 Times in 27 Posts
You should decide exactly what you want the engine to do and the rpm range you're going to run. Then decide on a cam that will fit those criteria and use the compression ratio that suits the cam.
Reply With Quote Quick reply to this message
  #3 (permalink)  
Old 12-13-2010, 08:31 AM
Member
 
Last photo:
Join Date: Dec 2004
Location: San Antonio, Texas
Age: 50
Posts: 4,021
Wiki Edits: 0

Thanks: 0
Thanked 23 Times in 23 Posts
cam timing has a huge effect on the amount of compression that can be/should be used.

If the cam is stock, then you could run 9 to 9.5 with aluminum heads.

I would use 9:1 if there is a big load on the engine (pulling a trailer).
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
AFR or Vortec heads? Cam? rodent Engine 18 06-08-2010 03:50 PM
Aluminum Heads scenario of potential problem of cause of oil consumption (long) y2k600f4 Engine 37 09-14-2009 05:22 PM
sbc heads shieldbreaker Engine 5 08-27-2005 08:12 PM
Heads and Intake combo black66 Engine 4 07-23-2005 11:33 PM
looking for some head(s) now i'm gonna explode! bullheimer General Rodding Tech 25 04-12-2004 01:16 PM


All times are GMT -6. The time now is 11:46 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.