modified dirt track transmission - Hot Rod Forum : Hotrodders Bulletin Board -- 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
lost password?   |   register now

LinkBack Thread Tools
  #1 (permalink)  
Old 07-07-2013, 10:25 PM
Registered User
Join Date: Jun 2012
Posts: 128
Wiki Edits: 0

Thanks: 0
Thanked 7 Times in 7 Posts
modified dirt track transmission

working on a modified dirt track car with a gm 3 speed trans. now we put a blow shield and mid engine plate on it and now the input shaft isn't long enough to reach the pilot bearing in the engine. there is no shorter bellhousing available or a longer input shaft for the gm 3 speed. im looking for ideas, anything at all

Reply With Quote Quick reply to this message
Sponsored Links
  #2 (permalink)  
Old 07-08-2013, 12:34 AM
OneMoreTime's Avatar moderator
Last wiki edit: Health and safety in the shop or garage
Last journal entry: Yard Dog pic
Last photo:
Join Date: Jul 2004
Location: Washington State
Age: 72
Posts: 8,843
Wiki Edits: 3

Thanks: 220
Thanked 459 Times in 410 Posts
If I recall there was an extended pilot bushing for that..if you cannot find one one could be made on a lathe.

I have tried most all of it and now do what is known to work..
Reply With Quote Quick reply to this message
  #3 (permalink)  
Old 07-09-2013, 03:58 PM
Registered User
Join Date: Jun 2012
Posts: 128
Wiki Edits: 0

Thanks: 0
Thanked 7 Times in 7 Posts
thanks, ill look for one
Reply With Quote Quick reply to this message
  #4 (permalink)  
Old 07-09-2013, 08:20 PM
Registered User
Join Date: Jun 2012
Posts: 128
Wiki Edits: 0

Thanks: 0
Thanked 7 Times in 7 Posts
I found a extra long pilot bushing at speedway for 14.99 thanks for input.
Reply With Quote Quick reply to this message
  #5 (permalink)  
Old 07-10-2013, 07:26 AM
Registered User
Last photo:
Join Date: Jun 2010
Location: Syracuse, NY
Posts: 3,851
Wiki Edits: 0

Thanks: 3,103
Thanked 656 Times in 541 Posts
I hope you see this. PLEASE check that sintered bronze pilot bushing for iron contamination. By design sintered bronze has some ferrous material in it. However it should NOT be chunks of iron/steel that are plainly visible and it should NOT be magnetic. If the bushing is attracted to a magnet, either in the ID or the OD, it can damage the pilot on the input gear OR the ID of the crank (pilot hole). Google Oilite Bronze Bushings. If your bushing is magnetic; send it back. If you get in a bind for an oilite one, let me know.

The sad thing is the oilite bronze doesn't cost much (ours comes direct from Beemer Precision), and Ive seen guys ruin a $3000 transmission to a shoddy bushing. I am also NOT a fan of needle bearings. if its not installed dead nuts square into the back of the crank, they can fail and damage the input gear as well. GM has a very high quality one over the counter I think from diesel applications(?). I prefer the bronze bushing because its more tolerant of bellhousing/scattershield misalignment.

This brings up my next point. Please spend some time with a dial indicator and properly align your bellhousing. Plenty of guys bring me their transmission because it jumps out of high gear, and its almost always severe bellhousing misalignment. For a performance application; .003 - .005 TIR is preferred. You could go out as far as .00750 TIR, and a street car can get by with .010 TIR. TIR is Total Indicated Runout which is NOT (for example) .003" off center to the left. .003" off center in one direction is actually .006 TIR. There are plenty of tutorials on to explain this better than I.
Reply With Quote Quick reply to this message

Recent Transmission - Rearend posts with photos

Quick Reply

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:
Please enter a password for your user account. Note that passwords are case-sensitive.
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:
Please select your insurance company (Optional)


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
dirt track racing bumble bee88952 Transmission - Rearend 1 12-27-2011 09:00 PM
Nascar Is Looking More Like Dirt Track crystalbluevib Hotrodders' Lounge 85 03-21-2010 10:07 PM
dirt track 305 groomer Engine 12 04-20-2008 02:46 AM
'20's and '30's dirt track racers Youngster Hotrodding Basics 2 08-26-2007 08:35 PM
modified dirt car motor john chaffin Engine 21 01-24-2005 04:07 PM

All times are GMT -6. The time now is 06:45 PM.

Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0 PL2
vBulletin Security provided by vBSecurity v2.2.2 (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
Copyright 1999 - 2012. All Rights Reserved.