350 sbc with 305 h.o heads will this work whats the ups and downs - Page 4 - 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
  #46 (permalink)  
Old 09-26-2012, 01:56 AM
Cridder's Avatar
Registered User
 

Last journal entry: 310 Small Block Chevy
Last photo:
Join Date: Oct 2010
Location: Nanaimo (Cedar) BC Canada
Posts: 61
Wiki Edits: 0

Thanks: 3
Thanked 2 Times in 2 Posts
hoggin the bowls

Quote:
Originally Posted by F-BIRD'88 View Post
Here is a pic of a fully ported 083 head.
You can see there is serious flow paths around the guide now.
These are not my heads but heads done at home by another guy who did not listen to the arm chair experts.
These 083 heads flow over 270cfm (2.08" valve)

When done generously @HOME with just a 1.94" valve they flowed over 240cfm.
At first glance they look like well ported heads, i don't like the duel flow paths philosophy, this type of head has a poor short side radius and as a result has poor flow on the bore center side of the valve, the typical fix is to bias grind the bowl and try and turn the air away from the wall side, smilier to a swirl port, material should not have been removed from the outside wall side of the bowl, if these flow 270 cfm it looks as though it will all be out the front, combustion efficiency and low speed will probably be poor.

    Advertisement
Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
  #47 (permalink)  
Old 09-26-2012, 02:23 AM
Cridder's Avatar
Registered User
 

Last journal entry: 310 Small Block Chevy
Last photo:
Join Date: Oct 2010
Location: Nanaimo (Cedar) BC Canada
Posts: 61
Wiki Edits: 0

Thanks: 3
Thanked 2 Times in 2 Posts
Compression ratio 350/305

Quote:
Originally Posted by bygddy View Post
Mine runs excellent, so far, only on 94 tho....I'm very curios as to my compression.....I know the heads were cut at some point, but didn't know how much until I went to install my intake, and with the 1094 headgasket, the intake bolts do not line up! Close, very actually but not enough to get one side in if the other has any bolts in. But the intake gaskets looked good with no surprises....is there a way to calculate compression based on say,cranking pressure or? I'm dying to know what I have.....and it seems I may have dodged a bullet with ptv by choosing a small cam ......I have had it to 6000 g's with no issue.....hmmm
No where in this thread is there a mention of piston type, from the picture they look like flat-tops, there was mention of heavly planning the heads, so based on 55cc for the heads it calculates out to 11.44:1.. cranking compression will be well over 200 psi.
Reply With Quote Quick reply to this message
  #48 (permalink)  
Old 09-26-2012, 05:07 AM
Proud LOSER
 
Last photo:
Join Date: Mar 2008
Location: Ottawa
Posts: 2,058
Wiki Edits: 0

Thanks: 82
Thanked 315 Times in 272 Posts
Quote:
Originally Posted by Cridder View Post
No where in this thread is there a mention of piston type, from the picture they look like flat-tops, there was mention of heavly planning the heads, so based on 55cc for the heads it calculates out to 11.44:1.. cranking compression will be well over 200 psi.
Dished, factory,..........and if you see my stupidity thread elsewhere, I discovered that while yes the heads were milled, it may not have been that drastic, as it turns out my "free" almost brand new procomp "performer" knock off, simply was garbage and didn't fit....!
Reply With Quote Quick reply to this message
The Following User Says Thank You to bygddy For This Useful Post:
smallblock383 (09-26-2012)
  #49 (permalink)  
Old 09-26-2012, 07:12 AM
Cridder's Avatar
Registered User
 

Last journal entry: 310 Small Block Chevy
Last photo:
Join Date: Oct 2010
Location: Nanaimo (Cedar) BC Canada
Posts: 61
Wiki Edits: 0

Thanks: 3
Thanked 2 Times in 2 Posts
Compression ratio 350/305

Quote:
Originally Posted by bygddy View Post
Dished, factory,..........and if you see my stupidity thread elsewhere, I discovered that while yes the heads were milled, it may not have been that drastic, as it turns out my "free" almost brand new procomp "performer" knock off, simply was garbage and didn't fit....!
Ok 15cc for the pistons, 58cc heads, tin gaskets + 025 in the hole = 9.78:1
Reply With Quote Quick reply to this message
  #50 (permalink)  
Old 09-26-2012, 04:46 PM
Proud LOSER
 
Last photo:
Join Date: Mar 2008
Location: Ottawa
Posts: 2,058
Wiki Edits: 0

Thanks: 82
Thanked 315 Times in 272 Posts
Quote:
Originally Posted by Cridder View Post
Ok 15cc for the pistons, 58cc heads, tin gaskets + 025 in the hole = 9.78:1
Figuring in minor de-shrouding, and they were cut at some point, I'm guessing your pretty close.....sounds just about right for a nice street motor to me!
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:
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
305 heads or 350 heads on sbc 355 ryan v Engine 5 09-20-2012 11:21 AM
SBC 305 Heads on a 350 ???? Brawler Engine 8 01-06-2009 10:48 PM
Will 305 Heads Work On A 350 Or 400 Sbc ?? STATUTORY GRAPE Engine 3 04-24-2005 09:10 PM
350 sbc..305 heads?? learjet60 Engine 6 01-28-2005 09:28 PM
305 vortec heads on a 350? Will they work? 70bird Engine 15 05-25-2004 04:32 PM


All times are GMT -6. The time now is 06:41 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.