350///357 build - Page 9 - 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
  #121 (permalink)  
Old 12-20-2012, 07:40 PM
Registered User
 
Join Date: Dec 2012
Posts: 15
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
might catch hell for even mentioning this, but IMO you can figure deck height fairly accurately with a dial caliper. when i originally assembled my engine(350 sbc) i borrowed a friends deck bridge and indicator to check mine. They were found to be .010-.011 in the hole.. the other day just for curiousity i had a degree wheel on and rotated it to bdc. Using the leg on my caliper i measured from the deck surface to the piston edge inline with the wrist pin. 3.491"... - 3.48" stroke = .011" ...thats close enough for gasket selection purposes. Beware if you tried this method at TDC the chamfers would ruin any hope for accuracy..

    Advertisement
Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
  #122 (permalink)  
Old 12-20-2012, 08:41 PM
techinspector1's Avatar
Senior Curmudgeon
 
Last wiki edit: DynoSim combinations Last photo:
Join Date: Oct 2005
Location: Hemet, California, USA
Age: 72
Posts: 13,322
Wiki Edits: 326

Thanks: 841
Thanked 1,153 Times in 952 Posts
Quote:
Originally Posted by cr480r View Post
Beware if you tried this method at TDC the chamfers would ruin any hope for accuracy..
As I say often, this stuff ain't rocket surgery
All you would need to get a very accurate measurement at TDC is a small framing square. Maybe I'm saying it wrong, but it's the flat measuring rule that is shaped like an L. Sit one side of the square down on the deck and butt the side of the dial caliper up against the other side of the square and measure with the slider on the caliper. There's room at the tip of the caliper to make contact with the deck and also to reach the crown of the piston with the slider part of the caliper.
Reply With Quote Quick reply to this message
  #123 (permalink)  
Old 12-20-2012, 09:34 PM
cobalt327's Avatar
WFO
 
Last wiki edit: Intake manifold
Last journal entry: 1980 Malibu Wagon
Last photo:
Join Date: Mar 2009
Location: Atlanta
Age: 60
Posts: 5,037
Wiki Edits: 1616

Thanks: 128
Thanked 598 Times in 547 Posts
After rocking the crank/piston to establish that you're at TDC, tap the top of the piston to seat the bearing against the crank journal. It won't make much difference (not more than ~ 0.002"), but it helps w/accuracy if you're measuring the all four corners to get a rough estimate of what the decks look like for being square.
Reply With Quote Quick reply to this message
  #124 (permalink)  
Old 12-20-2012, 10:10 PM
Registered User
 
Last photo:
Join Date: Aug 2011
Location: Fort Worth, TX
Posts: 522
Wiki Edits: 0

Thanks: 153
Thanked 11 Times in 10 Posts
Okay I will. What if we assumed all were within the. 037 -. 038 range? Just until I get it
to a position to measure all four..
Reply With Quote Quick reply to this message
  #125 (permalink)  
Old 12-20-2012, 10:43 PM
cobalt327's Avatar
WFO
 
Last wiki edit: Intake manifold
Last journal entry: 1980 Malibu Wagon
Last photo:
Join Date: Mar 2009
Location: Atlanta
Age: 60
Posts: 5,037
Wiki Edits: 1616

Thanks: 128
Thanked 598 Times in 547 Posts
Well, it wouldn't be good news, that's for sure. Getting a decent quench w/that much piston deck height isn't going to happen, not as things currently stand.

You have the option of one or more:

• shaving the decks
• using a taller compression height piston. If you have rebuilder pistons w/a 1.54 CH, that can gain you 0.020" (piston closer to deck)
• thinner head gaskets. The thinnest are 0.015" steel shims, they need a flat surface on both sides to seal to. The finish is important, too. That usually means a clean-up skim off the decks and heads for best results.
• You also could build it w/a less-than-perfect quench. Using a thin composite gasket (0.026-0.028") and your pistons you'd end up with about 0.065" quench. Definitely not ideal but I've seen worse. Not saying to do this, just saying.
Reply With Quote Quick reply to this message
  #126 (permalink)  
Old 12-20-2012, 10:52 PM
techinspector1's Avatar
Senior Curmudgeon
 
Last wiki edit: DynoSim combinations Last photo:
Join Date: Oct 2005
Location: Hemet, California, USA
Age: 72
Posts: 13,322
Wiki Edits: 326

Thanks: 841
Thanked 1,153 Times in 952 Posts
Quote:
Originally Posted by 1Gary View Post
Technically the chamber volume includes the space between the deck the top of the top ring.In cases where you where right at the rag-get edge of a limit then that would be important. Some piston companies move the top ring down because of the application and heat issues.
The OEM's have been moving the top ring up closer and closer to the crown just because of what you have addressed. The mixture that sits there between the piston and the bore never gets lit, so when the cylinder is evacuated, the unburned mixture contributes to dirty emissions.
Reply With Quote Quick reply to this message
  #127 (permalink)  
Old 12-21-2012, 12:37 AM
Registered User
 
Last photo:
Join Date: Aug 2011
Location: Fort Worth, TX
Posts: 522
Wiki Edits: 0

Thanks: 153
Thanked 11 Times in 10 Posts
wonderful
Reply With Quote Quick reply to this message
  #128 (permalink)  
Old 12-21-2012, 01:39 AM
1Gary's Avatar
Registered User
 

Last journal entry: 383 dyno sym
Last photo:
Join Date: Oct 2010
Location: Roch,NY
Age: 67
Posts: 1,541
Wiki Edits: 0

Thanks: 201
Thanked 156 Times in 142 Posts
Is your state/area emissions sensitive??.
Reply With Quote Quick reply to this message
  #129 (permalink)  
Old 12-21-2012, 08:21 AM
Registered User
 
Last photo:
Join Date: Aug 2011
Location: Fort Worth, TX
Posts: 522
Wiki Edits: 0

Thanks: 153
Thanked 11 Times in 10 Posts
Quote:
Originally Posted by 1Gary View Post
Is your state/area emissions sensitive??.
No. Currently, no.
Reply With Quote Quick reply to this message
  #130 (permalink)  
Old 12-21-2012, 08:22 AM
Registered User
 
Last photo:
Join Date: Aug 2011
Location: Fort Worth, TX
Posts: 522
Wiki Edits: 0

Thanks: 153
Thanked 11 Times in 10 Posts
Not for a 30 year old antique anyways.
Reply With Quote Quick reply to this message
  #131 (permalink)  
Old 12-21-2012, 06:33 PM
Registered User
 
Last photo:
Join Date: Aug 2011
Location: Fort Worth, TX
Posts: 522
Wiki Edits: 0

Thanks: 153
Thanked 11 Times in 10 Posts
Just got home with the motor stand, got the motor on the stand. Post measurements soon....
Reply With Quote Quick reply to this message
  #132 (permalink)  
Old 12-24-2012, 06:24 PM
Registered User
 
Last photo:
Join Date: Aug 2011
Location: Fort Worth, TX
Posts: 522
Wiki Edits: 0

Thanks: 153
Thanked 11 Times in 10 Posts
.038 on all four corners
Reply With Quote Quick reply to this message
  #133 (permalink)  
Old 12-25-2012, 03:50 AM
Registered User
 
Last photo:
Join Date: Jan 2011
Location: Hopewell, Va
Age: 62
Posts: 1,233
Wiki Edits: 0

Thanks: 0
Thanked 123 Times in 119 Posts
350///357 build

Well looks like you are going to have to use these Fel-Pro head gaskets. Fel-Pro Performance Head Gaskets Q1094 - SummitRacing.com. With these gaskets your quench will be .053. Could be worst. Static compression is 9.701 and DCR is 7.976 with 64cc heads. With 59cc heads 10.263 and 8.426.
Reply With Quote Quick reply to this message
  #134 (permalink)  
Old 12-25-2012, 11:49 AM
Registered User
 
Last photo:
Join Date: Aug 2011
Location: Fort Worth, TX
Posts: 522
Wiki Edits: 0

Thanks: 153
Thanked 11 Times in 10 Posts
Thats too high of compression isent it? Especially with more than ideal quench distance? I'm not sure what im going to do. Not even sure how hard it would be to disassemble the short block, send it to get decked, then reassemble. Obviously if I dont know how hard it is I have never done it and im pretty nervous about it. Im pretty certain I dont want to put it together like this. Pretty sure I need lower compression as well. Who knows what ill do. Probably end up selling this damn thing and getting something else.
Reply With Quote Quick reply to this message
  #135 (permalink)  
Old 12-25-2012, 03:25 PM
techinspector1's Avatar
Senior Curmudgeon
 
Last wiki edit: DynoSim combinations Last photo:
Join Date: Oct 2005
Location: Hemet, California, USA
Age: 72
Posts: 13,322
Wiki Edits: 326

Thanks: 841
Thanked 1,153 Times in 952 Posts
Quote:
Originally Posted by 0trbo4myCHEVUICK View Post
Thats too high of compression isent it? Especially with more than ideal quench distance? I'm not sure what im going to do. Not even sure how hard it would be to disassemble the short block, send it to get decked, then reassemble. Obviously if I dont know how hard it is I have never done it and im pretty nervous about it. Im pretty certain I dont want to put it together like this. Pretty sure I need lower compression as well. Who knows what ill do. Probably end up selling this damn thing and getting something else.
You'll have the same issues with "something else"
Building a motor is not just bolting on a bunch of parts and hoping for the best, not if you want to do it properly and have a quality piece at the end. I have put motors together 3 or 4 times and had them back apart, fixing stuff and making changes and I'll bet other builders will tell you the same thing.
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
trying to build a 357 Newbie3191 Engine 8 07-01-2010 11:10 AM
HP and TQ Guesses of my 357 build ORANGEGASM Engine 2 08-13-2008 08:08 PM
357...??? jkingof9561 Engine 2 05-04-2008 04:18 PM
357 ci chevy bstout3 Engine 1 11-20-2004 07:00 PM
breaking in my 357... Sagacious Engine 3 08-05-2004 05:51 PM


All times are GMT -6. The time now is 02:45 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.