stalling a Pete Jackson Gear Drive in a SPC - 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 06-21-2006, 08:49 PM
Registered User
 
Join Date: Jun 2006
Location: fairfax vt
Posts: 3
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
installing a Pete Jackson Gear Drive in a SPC

I am installing a PJ gear drive in 1970 LT1 370 hp and changing mech. cam .484 lift to a mech cam .520 lift. I lost my instructions to gear drive installation need help with the dot alignment thing. I set the dot on the crank @ 12:00 and the dot on the cam @ 12:00 (#1 piston up at max). I installed roller- rocker with .016 set clearance on intake and exhaust at this position. I rotated crank clockwise until max lift was reached for #1 intake and exhaust. At these postions, I over- traveled valve by hand to measure valve to piston clearance (note: I changed out valve spring to a 3 lb spring for this test only) Is this procedure correct??? I thought my piston would have been closer to valve. Am I checking clearance at proper timing?? Help please!

    Advertisement

Last edited by tim gleason; 06-22-2006 at 07:33 PM.
Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
  #2 (permalink)  
Old 06-22-2006, 06:07 AM
Hotrodders.com Moderator
 

Last journal entry: PICTURE TEST
Last photo:
Join Date: Jan 2004
Location: york pa
Age: 52
Posts: 2,795
Wiki Edits: 0

Thanks: 0
Thanked 1 Time in 1 Post
engine

Ok well, where to start???

You can align the dots at 12:00 or 6:00 because it is a direct 1/2 speed relationship between the cam and crank. In other words if you put the crank at 12:00 and the cam at 12:00 and then rotate the engine 1 full turn the dots are now at 12:00 and 6:00.... They just need to be aligned,,,, really the cam needs to be degreed. But that another story..


You need to check the piston to valve clearance from 20 deg BTDC to 20deg ATDC.. this is the location where the valve is closest to the piston, not at max valve lift... I personally hate checking springs, all my measurments are done in race ready condition...thats just my opinion... In your case the checking springs will work.

Rotate the engine until your 20 deg BTDC install the dial indicator on the retainer, make sure the plunger travel is parallel to the spring travel. Pull the valve open until it contacts the piston and check you indicator reading, then rotate the engine 2 degrees to 18 BTDC and check again. Do this every 2 deg until you get to 20 deg ATDC....

Don't get suprised if you travel the indicator .250" or more and never touch the piston.....


Keith
Reply With Quote Quick reply to this message
  #3 (permalink)  
Old 06-22-2006, 07:54 PM
Registered User
 
Join Date: Jun 2006
Location: fairfax vt
Posts: 3
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
pj gear drive & valve clearance check

thanks Keith for help . i did as you directed the result look good.
closest was @ 4 deg. before tdc valve clearance was .253" on exhaust
and .278" on intake . does this seem correct?? remember 1970 LT-1 was 11:1
comp. ratio , so my piston are trw with .1 high dome (#L2304 TRW piston). also note using EDLELBROCK E-TEC 200 ALUM HEADS. EVERYONE was saying
my valves would probably hit piston. any thougths!?!?

regards,
TIM
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
Pete Jackson gear drive? chevyelc81 Engine 1 03-31-2008 10:04 PM
PJ Gear Drive bonuts Engine 2 12-09-2003 10:33 PM
Gear Drive heather051599 Engine 2 11-21-2003 07:36 AM
gear drive with roller's 351windsor Engine 2 06-24-2003 09:42 PM
Pete Jackson Dual Idler Ger Drive HR Wilson Engine 0 12-23-2002 06:25 AM


All times are GMT -6. The time now is 05:11 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.