Distributor question
Thread Starter
Racer
Joined: Jan 2008
Posts: 299
Likes: 4
From: Surprise AZ
Distributor question
Hi, On a 78 vet 350, took out the delco remy distributor and replaced it with a Mallory 8548201. It looks like it is one tooth off,even moving the oil pump shaft. Put back the delco Remy distributor and it is right on the money. Confussed.Any help Thanks. 
Drifting
Joined: Mar 2011
Posts: 1,347
Likes: 121
From: Kernersville NC
Did you check and adjust the timing or just drop it in close to the same position as the old one and hope timing was the same? I Changed from Mallory to MSD and the #1 plug terminal was not in exactly in the same position. It was about 1/2 click clockwise from the old one. One gear tooth in either direction put #1 way off from the normal position. It's just the way the gear is clocked to the shaft when they drill and pin it.
Last edited by flyeri; Jan 17, 2015 at 06:07 PM.
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,118
From: Crossville TN
It could be 1/2 tooth off. The [lower] drive gear has an odd number of teeth; and it can be pinned to the shaft either of two ways, 180* apart. Regardless of how the dizzy is assembled, you should still be able to get it timed properly. If you just want the advance can to be located in the same place, try removing the drive gear, rotate it 180* and reinstall it.
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,118
From: Crossville TN
Can't answer that question...not enough knowledge of the Mallory unit's guts. But, you can always re-clock ANY distributor by shifting all the plug wires one direction (or the other) to get the dizzy positioned as you need. I can't imagine the combination of re-clocking and rotating the drive gear not providing you with what you need.
Race Director
Joined: Jul 2001
Posts: 15,892
Likes: 42
If not, why not?
Drifting
Joined: Feb 2005
Posts: 1,879
Likes: 38
From: Los Gatos CA
There is no such thing as "1 tooth off". You can stab distributer any way; figure out which terminal the rotor is pointing to at #1 cylinder tdc compression stroke and route wires based on firing order. The engine does not know the difference.
"Proper" distributer phasing enables wire routing, etc.
If you do not have enough adjustment clearance just pull distributer and rotate rotor a little and re-stab. Easy money. Have fun with it!
"Proper" distributer phasing enables wire routing, etc.
If you do not have enough adjustment clearance just pull distributer and rotate rotor a little and re-stab. Easy money. Have fun with it!
Drifting
Joined: Mar 2006
Posts: 1,263
Likes: 188
From: Wabasha Mn
Some of the lower priced hei units from accel , msd, and mallory are now made in china so your old delco hei is probably a good candidate for a Lars rebuild. I would not start mixing parts from the mallory to your oem dizzy except for maybe rotor and cap.
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Tech Contributor
Joined: Aug 1999
Posts: 14,382
Likes: 6,402
From: At my Bar drinking and wrenching in Lafayette Colorado
There is no such thing as "1 tooth off". You can stab distributer any way; figure out which terminal the rotor is pointing to at #1 cylinder tdc compression stroke and route wires based on firing order. The engine does not know the difference.
"Proper" distributer phasing enables wire routing, etc.
If you do not have enough adjustment clearance just pull distributer and rotate rotor a little and re-stab. Easy money. Have fun with it!
"Proper" distributer phasing enables wire routing, etc.
If you do not have enough adjustment clearance just pull distributer and rotate rotor a little and re-stab. Easy money. Have fun with it!
That's correct. You can technically install the distributor in any location/orientation that permits the timing to be correctly set without the vacuum advance hitting engine components and limiting timing range. If the timing can be set, the installed orientation is irrelevant except for cosmetic reasons. So stab it in at about the right location, and set the timing. Once timing is properly set, take a look at the distributor's "clocking" and evaluate: An HEI, with timing set right, should be "square" in the engine compartment with the hook-up terminals pointing directly to the driver's side of the car, and with the square top-mounted coil "square" in the engine compartment. If it's not, lift the distributor up, move it one tooth, and re-set timing.
Lars
