L98 Distributor Shims
Thread Starter
Drifting
Joined: May 2001
Posts: 1,726
Likes: 1
From: COCOA Florida
L98 Distributor Gear Shims
Hi, I cannot find the clearance for the distributor gear/shaft assembly on an 86 vet. someone said it was like .050 but that seems like a lot of movement vertically. Can anyone direct me to info or what do you shim the distributor to when rebuilding. Thanks in advance.
[Modified by C4TOMCAT, 4:54 AM 11/4/2002]
[Modified by C4TOMCAT, 4:54 AM 11/4/2002]
Racer
Joined: Jul 2000
Posts: 421
Likes: 0
From: Glen Burnie Md
Re: L98 Distributor Gear Shims (C4TOMCAT)
Shim your distributor 'end play' to .025."
You can pick up the shims at your local performance shop. They come packaged...with various thicknesses to take up the slack.
You can pick up the shims at your local performance shop. They come packaged...with various thicknesses to take up the slack.
Thread Starter
Drifting
Joined: May 2001
Posts: 1,726
Likes: 1
From: COCOA Florida
Re: L98 Distributor Gear Shims (UDLUV12)
Thanks for the reply...what difference will it make if it is less or more than that. does it impact the spark jumping in the distributor cap either way or just gear wear/bushings.
Racer
Joined: Jul 2000
Posts: 421
Likes: 0
From: Glen Burnie Md
Re: L98 Distributor Gear Shims (C4TOMCAT)
Shimming the distributor...is mostly about the timing.
Try picturing the following: Lets say you didn't shim the distributor, and the 'wear' becomes even greater over time.
By 'wear' I'm referring to the cam gear and distributor gear.
As you increase your RPM's over time, the distributor gear tends to 'raise' itself 'off' the cam gear, thus the meshing of the gears tend to extend themselves more and more apart from each other.
What this eventually leads to is a 'jump' in timing.
By shimming the distributor, you avoid this problem from happening.
Try picturing the following: Lets say you didn't shim the distributor, and the 'wear' becomes even greater over time.
By 'wear' I'm referring to the cam gear and distributor gear.
As you increase your RPM's over time, the distributor gear tends to 'raise' itself 'off' the cam gear, thus the meshing of the gears tend to extend themselves more and more apart from each other.
What this eventually leads to is a 'jump' in timing.
By shimming the distributor, you avoid this problem from happening.
Le Mans Master
Joined: Mar 1999
Posts: 6,744
Likes: 1
From: delmont pa
Cruise-In I Veteran
Cruise-In II Veteran
Re: L98 Distributor Gear Shims (C4TOMCAT)
if the housing is cast iron you can shim down to .005/.007 and if the housing is aluminum go for .010. this will help cut down on the "spark scatter" make sure that the shims you use are "hardened" :chevy
[Modified by clem zahrobsky, 6:45 PM 11/4/2002]
[Modified by clem zahrobsky, 6:45 PM 11/4/2002]
