Piston Rings - 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 03-11-2004, 02:36 PM
Erk Erk is offline
Member
 
Join Date: Feb 2004
Location: Vincennes,IN
Age: 26
Posts: 112
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Piston Rings

What are the set measurements for standard moly piston rings?
Out of vizards book its
.014-.018 top compression ring(these are not exact but very close, this is what i remember as are the other ones)
.018-.025 on 2nd compression ring
and on Both oil rings its .025-.050.
Now those seem a bit iffy..What should they be or is this what i need/want them to be?

-Eric

    Advertisement
Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
  #2 (permalink)  
Old 03-11-2004, 02:54 PM
lluciano77's Avatar
Short changed on common sense
 
Last photo:
Join Date: Jun 2003
Location: california
Age: 37
Posts: 3,548
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
For hyperuetectics the gap is different. There is a formula you use to figure what you need. It all depends on what the piston manufacturer and the ring manufacturer specify. I would go with what the piston manufacturer says first, unless it is less gap than what the ring manufacturer says. Always err to the big side.
Reply With Quote Quick reply to this message
  #3 (permalink)  
Old 03-11-2004, 05:48 PM
Erk Erk is offline
Member
 
Join Date: Feb 2004
Location: Vincennes,IN
Age: 26
Posts: 112
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
How can i find this out? My pistons did NOT come with a card that shows how much gap.

-Eric
Reply With Quote Quick reply to this message
  #4 (permalink)  
Old 03-11-2004, 11:47 PM
Member
 
Last photo:
Join Date: May 2003
Location: Shreveport LA
Age: 64
Posts: 5,103
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
KB hypereutectics run the top ring higher, & as a result the gap needs to be bigger due to the greater heat causing more expansion of the steel. A Federal Mogul guy told me their hyper's use the " normal" ring gap. The "normal" rule of thumb is .004" per inch of cylinder bore for a normally-aspirated engine. Here's the chart for KB's:

http://kb-silvolite.com/article.php?...0dfb73b419cd6d
Reply With Quote Quick reply to this message
  #5 (permalink)  
Old 03-12-2004, 09:00 AM
machineman's Avatar
New Member
 
Join Date: Mar 2004
Location: Baltimore, MD
Age: 45
Posts: 18
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Determining piston ring gap is a case by case basis. Will you be running nitrous? a blower? extreme RPM? piston type? marine? These types of uses need to be addressed before a ring gap should be determined.

Keep one thing in mind, when in doubt go wider. Too wide of a ring gap has shown very little affect in dyno tests. Too narrow a ring gap causes all kinds of problems and none of them are very good for the overall life of the engine.
Reply With Quote Quick reply to this message
  #6 (permalink)  
Old 03-12-2004, 02:50 PM
Erk Erk is offline
Member
 
Join Date: Feb 2004
Location: Vincennes,IN
Age: 26
Posts: 112
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
The are federal-mogul-sealed power-speedpro 9.35:1 hypereutectics..They didn't come with a sheet that shows the gaps for some reason..I will be turning around 5500rpm's.So what your saying is that i can use KeithBlacks chart and use those gaps on my speedpro's

-Eric
Reply With Quote Quick reply to this message
  #7 (permalink)  
Old 03-12-2004, 03:12 PM
King of my Man-cave.
 
Last photo:
Join Date: Nov 2003
Location: Michigan
Age: 55
Posts: 2,899
Wiki Edits: 0

Thanks: 3
Thanked 15 Times in 12 Posts
NO. Don't use KB info for SP pistons. The ring end gap will be too wide. SP Hypers use standard ring end gap factors. You may go a little more to be safe. Use the ring manufactures guide as a starting point.
Reply With Quote Quick reply to this message
  #8 (permalink)  
Old 03-12-2004, 06:11 PM
Erk Erk is offline
Member
 
Join Date: Feb 2004
Location: Vincennes,IN
Age: 26
Posts: 112
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Well i checked out their website and for 4.000 - 4.999" bore
Then gaps for all rings are ".012 - .025"., That sound about right? this is my first rebuild btw..

-Eric
Reply With Quote Quick reply to this message
  #9 (permalink)  
Old 03-12-2004, 08:33 PM
Erk Erk is offline
Member
 
Join Date: Feb 2004
Location: Vincennes,IN
Age: 26
Posts: 112
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
ttt

-Eric
Reply With Quote Quick reply to this message
  #10 (permalink)  
Old 03-13-2004, 10:00 PM
Erk Erk is offline
Member
 
Join Date: Feb 2004
Location: Vincennes,IN
Age: 26
Posts: 112
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
ttt once again
I just need to know if those ring gaps will work..the 3rd to last post of mine.

-Eric
Reply With Quote Quick reply to this message
  #11 (permalink)  
Old 03-13-2004, 10:42 PM
camaroman7d's Avatar
Member
 
Last photo:
Join Date: Dec 2003
Location: Vacaville, California
Age: 47
Posts: 2,245
Wiki Edits: 0

Thanks: 3
Thanked 9 Times in 9 Posts
you posted a very wide range .012-.025 that is broad. If you are running nitrous, forced induction, etc.. then go on the wider side.

If this is a mild build for a street car then you don't need as wide of a gap.

To answer your question yes that range looks fine. If your pistons came with rings, check the end gap and see where it sits out of the box. They may not even be file fit rings (sure all rings can be filed), I would guess they came "pre-gapped"

As machineman said it depends on the application and you set the gap accordingly. You just really don't want them to butt or you will break the piston/s.

Royce
Reply With Quote Quick reply to this message
  #12 (permalink)  
Old 03-13-2004, 10:43 PM
Grumpy
 
Last photo:
Join Date: Dec 2002
Location: D.C.
Posts: 1,447
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Total seal gapless rings!

sorry had to add it.
Reply With Quote Quick reply to this message
  #13 (permalink)  
Old 03-13-2004, 10:57 PM
GSXMEN's Avatar
Member
 
Last photo:
Join Date: Feb 2004
Location: Upstate, NY
Age: 49
Posts: 152
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
You still have to check the gap on the Total Seal rings.

I wouldn't run the rings less than .018" personally. Modern thinking on ring gaps has the 2nd ring larger than the 1st.
Reply With Quote Quick reply to this message
  #14 (permalink)  
Old 03-14-2004, 10:08 AM
Erk Erk is offline
Member
 
Join Date: Feb 2004
Location: Vincennes,IN
Age: 26
Posts: 112
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Its a mild street build..naturally aspirated..
Alright thanks for the info guys..
-Eric
Reply With Quote Quick reply to this message
  #15 (permalink)  
Old 03-15-2004, 03:17 PM
Erk Erk is offline
Member
 
Join Date: Feb 2004
Location: Vincennes,IN
Age: 26
Posts: 112
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Final Verdict.

1st Compression Ring- I set all around .018
2nd Compression Ring-I set all around .025
Oil Rings-All about .025-.030.

-Eric
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



All times are GMT -6. The time now is 12:16 AM.


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.