Axle Housing Install - Pinion Angle Help - 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> Transmission - Rearend
User Name
Password
lost password?   |   register now

Reply
 
LinkBack Thread Tools
  #1 (permalink)  
Old 01-07-2007, 10:41 AM
72NOVA454
 
Last photo:
Join Date: Nov 2004
Location: chicago area
Age: 52
Posts: 922
Wiki Edits: 0

Thanks: 0
Thanked 2 Times in 2 Posts
Axle Housing Install - Pinion Angle Help

Help

I'm done with the rearend upgrade and the housing is back the car with leaf springs attached, etc. Driveshaft not connected yet.

How do I setup the pinion angle/driveshaft angle?

In other words, I need to "rotate" the entire housing so the angle is right?

I can basically eyeball it so "looks right" but I know I can do better than that. What' the correct method to set this up?

It's connecting to a TH-350 trans.

It's for a 72 Nova

thanks.

Lee

    Advertisement
Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
  #2 (permalink)  
Old 01-07-2007, 11:03 AM
pmeisel's Avatar
Glad the Jeep is on the road
 
Last wiki edit: How to identify a Ford V8
Join Date: Jan 2004
Location: Meridian MS & Vermilion Ohio
Age: 58
Posts: 814
Wiki Edits: 8

Thanks: 0
Thanked 1 Time in 1 Post
I have not set this up myself from scratch, but I know from fooling with the Jeep suspension that you don't really want the angle to be pointed right at the tranny -- you want the u-joints to flex 2 or 3 degrees. The pinion angle should point slightly below the centerline of the transmission output shaft (like maybe one inch... I don't have my trig function calculator handy...)

check this link for a diagram and description...

http://www.4xshaft.com/driveline101.html

I remember 2 to 3 degrees as a typical OEM setup to achieve a near zero angle when under load. According to the 4x4 guys you can go more than this and it still works but will increase U-joint wear. Somewhere around 10-15 degrees you will get some vibration...
Reply With Quote Quick reply to this message
  #3 (permalink)  
Old 01-08-2007, 02:59 PM
johnsongrass1's Avatar
Race it, Don't rice it!
 
Last photo:
Join Date: Jul 2002
Location: Columbia, Mo
Age: 38
Posts: 4,239
Wiki Edits: 0

Thanks: 0
Thanked 30 Times in 28 Posts
I find about anything over 7 and you'll tear up u joints depending axle wrpa of course. Use shim wedges under the leaf plates to get the rear end in the right direction. You'll need the car "race ready" so to speak. This cannot be dome with the car jackedup though.
Reply With Quote Quick reply to this message
  #4 (permalink)  
Old 01-08-2007, 03:06 PM
Registered User
 
Last wiki edit: Mopar tapered axle rear brake conversion
Last journal entry: What I'm doing now...
Last photo:
Join Date: Jan 2002
Posts: 4,267
Wiki Edits: 49

Thanks: 0
Thanked 5 Times in 5 Posts
The information in this post was collected from several different articles on the subject and a number of web sites. Where quotes are used the author is directly credited for his statements.

If you talk to a dozen car guys about pinion angle you?re going to get 12 different opinions. Why? Because optimum pinion angles and settings will vary depending on things such as intended use and suspension type. What works for one suspension type under one condition may not work for another. Sounds confusing doesn?t it. That?s probably why so many people ask for help on this subject. Let?s try to explain some of this mystery.

The guidelines below are specifically recommended for street driven vehicles. Settings for drag racing will differ and are especially dependent on suspension type. For instance a 4 bar rear suspension has much more control over the pinion angle under all operating conditions than a parallel leaf spring suspension does. Therefore pinion angle can be much better controlled with a 4 link and the required pinion angle can be somewhat less than a leaf spring setup. This applies to racing only. When it comes to a street driven vehicle, which is the subject of this post, the recommendations below apply no matter what suspension is used.

First we have to understand what pinion angle is. For our purpose pinion angle is defined as the angle of the pinion in relation to the angle of the drive shaft. This is measured referencing absolute level or for all intense and purposes, the ground. In the example below the angle of the drive shaft is 3* down in relation to level and the pinion is set 1* nose down in relation to level. This makes the effective pinion angle -4*.





The angle of the pinion gear isn?t the only important angle we have to deal with. There are other angles and components at play and they all have to work together to successfully transmit the engine?s power to the axles. The pinion angle?s relationship to the transmission output shaft angle (or crankshaft angle) and driveshaft angle is also extremely important. This relationship defines the angles at which the ?U? joints operate and according to Ray Currie of Currie enterprises, ?universal joints are designed to handle angles between 1 and 3 degrees. If a U-joint is forced beyond this normal range, it can hyperextend and lead to catastrophic failure.? In the example above the ?U? joint would be operating at 4 * or outside its designed parameters. This is why we need to control the relationship between pinion angle, the angle of the drive shaft and the angle of the transmission. Each affects the other.

According to Currie, ?a street driven vehicle should strive for between 1 and 3 degrees between the transmission and driveshaft, and 1 to 3 degrees between the driveshaft and pinion. Furthermore, the two angles should be nearly equal (between 1 and 3 degrees), but always opposite.? Otherwise stated, ideally, the angles between the transmission output shaft and driveshaft, and between the driveshaft and the pinion will be equal and opposite and 3 degrees or less. See the example below.





When setting pinion angle it is important to remember that exceeding the above parameters will result in premature wear of ?U? joints and angle induced vibrations in the drive train. Greg Frick of Inland Empire Driveline explains it this way. ?As the front U-joint gets the power delivered to the driveshaft, it transforms smooth engine power into pulsating power. This happens because the U-joint travels an elliptical path caused by the angle through which it operates. You can visualize this by looking at a dinner plate straight on.





If you tilt it the round plate appears to become an ellipse. In traveling this ellipse, the U-joint speeds up and slows down twice per shaft revolution. A second U-joint having an equal but opposite angle is used to convert this pulsating power back into smooth power feeding the pinion. The bigger the working angles are, the more violent these speed changes become.? Deliberately setting the pinion at a lesser angle is common on drag cars where the drive line is generally under full power however using this type setup on the street will result in annoying vibrations every time you back off the throttle. This is why it is extremely important to limit the angles to 3* or less.

In summary, it isn?t just the pinion angle that?s important. It?s the relationship between the driveshaft, transmission output shaft, and the pinion gear that is important and this relationship governs the angles at which the ?U? joints operate. It?s really not that difficult. All you have to do is keep the pinion angle and the transmission output shaft angles as close to parallel as possible and try to keep both angles at 3* or less. This is relatively easy for a full sized vehicle but the shorter the drive shaft the harder it is to control these angles.

There is also a school of thought that having some pinion angle is not required. Yes a driveline will work with 0 pinion angle however the "U" joints need a slight angle for proper lubrication. Running with 0 angle will prematurely wear out "U" joints.
Reply With Quote Quick reply to this message

Recent Transmission - Rearend 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
split straight front axle with rack and pinion dmcurry22 Suspension - Brakes - Steering 15 01-09-2009 12:15 AM
Straight Axle and Rack & Pinion Murff Suspension - Brakes - Steering 12 06-15-2004 04:21 AM
Review of FatMan IFS Airbag install 1938 Chevy PU Grashopr Suspension - Brakes - Steering 3 08-26-2003 12:16 AM
Setting Pinion Angle? 41willys Transmission - Rearend 5 11-09-2002 09:37 PM


All times are GMT -6. The time now is 09:58 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.