Are my connecting rods machined wrong? Which way to install pistons? - 460 Ford Forum
460 Ford Forum  
Go Back   460 Ford Forum > Tech Topics > Engine Tech

Engine Tech A place to discuss all 385-series engine tech and theory.

460Ford.com is the premier 460 Ford Forum on the internet. Registered Users do not see the above ads.
Reply
 
Thread Tools Search this Thread Display Modes
  #1  
Old 09-29-2012, 04:37 PM
cvfracing cvfracing is offline
Junior Member
 
Join Date: Apr 2012
Posts: 28
cvfracing First On Race Day
Default Are my connecting rods machined wrong? Which way to install pistons?

I am putting together a 545 stroker and I think that the rods on my stroker kit are machined with the chamfer and tangs on the wrong side but I wanted to get a second opinion. I'm going to try and attach some photos but not sure if I have sufficient permission yet.



1st photo shows the original rod cap (right) to the new one (left). Both have the lettering at the top of the photo but the large chamfer and bearings are on the opposite sides.



2nd photo shows where I was installing the rods and ran into trouble. I can't get both connecting rods on the crank because the large chamfers are on the inside instead of the outside. You can see that the lettering and bearing tang is outboard like it is supposed to be but the chamfer is on the wrong side.

I wanted to see if it is ok to just flip my connecting rods around and put the bearing tangs facing inboard instead of outboard. That would put the larger chamfer on the correct side but would put the bearing tangs on the wrong side.



3rd photo is my pistons. They are 40 cc dish Mahle forged pistons. I am pretty sure that the relief is an exhaust valve relief but I want to make sure. There aren't any markings on the piston to tell me which side goes foward so I'm just lining up the relief with the exhaust valves (front of the engine on cylinder 1-4 and facing back of engine on 5-8). The heads are edlebrock RPM and it seems like the exhaust valve is the one that would hit rather than the intake.

Last edited by cvfracing; 09-29-2012 at 04:40 PM.
Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
  #2  
Old 09-29-2012, 05:35 PM
Paul Kane's Avatar
Paul Kane Paul Kane is offline
Premium Member
 
Join Date: Jan 2006
Location: Bay Area, CA
Posts: 5,176
Paul Kane A Ford God!Paul Kane A Ford God!Paul Kane A Ford God!Paul Kane A Ford God!Paul Kane A Ford God!Paul Kane A Ford God!Paul Kane A Ford God!Paul Kane A Ford God!Paul Kane A Ford God!Paul Kane A Ford God!Paul Kane A Ford God!
Cool

  • The valve relief in your aftermarket forged pistons is an intake valve relief, not an exhaust valve relief.
  • On your OEM stock rods with the cast production pistons with offset pin, 4 rods are fit to the OEM pistons one way and the other 4 rods are fitted the opposite way; assemble in the engine block accordingly.
  • On your aftermarket rods with forged pistons, all rods go on the same way. In this case, the chamfer on the con rod big end should be on the same side and directly beneath the intake valve relief on the forged pistons.
Then check your bearing tangs.

Paul
__________________
We're On The Web; Click Below:
High Flow Dynamics
Performance Components for the 429/460 Engine Family
Reply With Quote Quick reply to this message
  #3  
Old 09-30-2012, 08:54 AM
cvfracing cvfracing is offline
Junior Member
 
Join Date: Apr 2012
Posts: 28
cvfracing First On Race Day
Default

Paul,

Thanks! That helps a lot. I set up my aftermarket rods & pistons like you described and everything seems right. The only problem is that it puts the lettering and tangs on the inboard side of the engine instead of facing out towards the freeze plugs. All the traditional wisdom out there says to keep the lettering and tangs pointing towards the outside of the engine but I can’t do that and still get the chamfers on the conn rods to line up correctly with the radius on the crank if I do that.

I guess that is just a chevy thing??? Does this photo look right? You guys are AWESOME!! Some punk at Summit racing would have given me bad advice…even the mechanic who did my machining was saying to install based on the tangs / lettering.

Reply With Quote Quick reply to this message
  #4  
Old 09-30-2012, 09:37 AM
2slow 2slow is offline
Senior Member
 
Join Date: May 2007
Posts: 3,479
2slow Driving a Ford
Default

your piston valve relief correct location ? intake on top right side ? if so

you have the rod installed on piston wrong , turn it around
Reply With Quote Quick reply to this message
  #5  
Old 10-01-2012, 09:04 AM
cvfracing cvfracing is offline
Junior Member
 
Join Date: Apr 2012
Posts: 28
cvfracing First On Race Day
Default

The intake relief on the pistons is in the upper right (rearward on cyl 5-8 and forward on 1-4). I don't think that flipping the pistons on the rods will help...that is the way I had them for the first set of photos.

I gone over this a hundred times in my head and a dozen times with the actual parts. I don't see any way to put the rods in such that the tangs and lettering are facing outboard towards the freeze plugs. If I put them in so that the lettering and tangs are correct then the bearings are wrong (ie with the small chamfer and bearing hitting the radius on the crank).

I think they put the large radius and tangs on the wrong side. Does anyone see any issue running with the bearing tangs facing inward as long as the chamfer is correct and the bearings aren't hitting the radius in the corner of the crank Journal?
Reply With Quote Quick reply to this message
  #6  
Old 10-01-2012, 09:58 AM
forestg forestg is offline
Junior Member
 
Join Date: Apr 2006
Posts: 41
forestg Driving a Ford
Default

On my stroker cleveland using chevy rods the tangs were installed inboard and ran fine for years.
Reply With Quote Quick reply to this message
  #7  
Old 10-01-2012, 11:02 AM
White Lightning's Avatar
White Lightning White Lightning is online now
Senior Member
 
Join Date: Feb 2010
Posts: 4,858
White Lightning First On Race Day
Default

It makes NO difference where the bearing tangs are. It makes EVERY difference where the large radius chamfer is. Don't obsess about the tangs or lettering.
Rob
__________________
Rob Hawes-Anchorage Rod Works-Anchorage, Alaska
Reply With Quote Quick reply to this message
  #8  
Old 10-01-2012, 11:54 AM
Lem Evans Lem Evans is online now
Senior Member
 
Join Date: Jan 2006
Location: Livermore Ky
Posts: 8,041
Lem Evans Walks on the Blue PathLem Evans Walks on the Blue PathLem Evans Walks on the Blue PathLem Evans Walks on the Blue PathLem Evans Walks on the Blue PathLem Evans Walks on the Blue PathLem Evans Walks on the Blue PathLem Evans Walks on the Blue Path
Default

Yep, large chamfer toward the cheek of the crank.
__________________
B F Evans Race Parts
270-278-2376
Reply With Quote Quick reply to this message
  #9  
Old 10-01-2012, 12:03 PM
cvfracing cvfracing is offline
Junior Member
 
Join Date: Apr 2012
Posts: 28
cvfracing First On Race Day
Default

Thanks Guys!!! That makes me feel a whole lot better! I would hate to screw this up. It's my first engine build and I am totally amazed at how many things are easy to screw up! (piston rings upside down, pistons or rods in backwards, bearings in wrong and so on)
Reply With Quote Quick reply to this message
  #10  
Old 10-01-2012, 03:27 PM
2slow 2slow is offline
Senior Member
 
Join Date: May 2007
Posts: 3,479
2slow Driving a Ford
Default

Quote:
Originally Posted by cvfracing View Post
Thanks Guys!!! That makes me feel a whole lot better! I would hate to screw this up. It's my first engine build and I am totally amazed at how many things are easy to screw up! (piston rings upside down, pistons or rods in backwards, bearings in wrong and so on)
the 2nd pic show the rod needs to be turned around if the piston is in the bore correct
Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
Reply

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the 460 Ford Forum forums, you must first register.
Please enter your desired user 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.



Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

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

Forum Jump


All times are GMT -5. The time now is 11:14 AM.



Powered by vBulletin® Copyright ©2000 - 2014, vBulletin Solutions, Inc.

Garage Plus vBulletin Plugins by Drive Thru Online, Inc.