• When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.

Advance springs correct?

69 origownr

Member
Local time
2:53 AM
Joined
Dec 13, 2014
Messages
12
Reaction score
0
Location
Los Angeles
Let me begin by saying I know little to nothing about distributor advance. Here is my situation: I am restoring a 1969 Dodge Charger R/T with a 440 Magnum engine. I've disassembled the distributor and noticed that the advance springs are different. I understand that this was done to increase the advance. My question is: would it come from the factory like this? Is this the best setup to be using? Should I leave it alone?
The only major change I've made was to put in a 2200 rpm stall converter and a slightly modified cam.
Distributor.JPEG


distributor tag.JPEG
 
They look like they could be stock. Maybe Halifaxhops will chime in. The one with the big loop was to give it sort of a two phase advance curve with the other, shorter spring allowing the initial curve to come in somewhat fast, up to a point. And then the big spring, when it’s slack was used up would slow the remaining curve from coming in until high rpm.
 
They look like they could be stock. Maybe Halifaxhops will chime in. The one with the big loop was to give it sort of a two phase advance curve with the other, shorter spring allowing the initial curve to come in somewhat fast, up to a point. And then the big spring, when it’s slack was used up would slow the remaining curve from coming in until high rpm.
Which would make the motor snappy, no?
 
They look stock to me.
Back in the 60's I would remove the heavy
spring and just run the light one if I had
a bit larger than stock cam.
 
AN OEM standard distributor used two different springs as AR67GTX said and for that reason. Those sure look like original. It may not be optimal, but the factory had to cover a lot of situations.
Back in the day, early '70's another "trick" was to braze up the slots to limit the mechanical travel, use a lighter spring to replace the heavy one, then set it so you would get 32-34 total, and adjust the static timing accordingly, meaning more static timing. Also disconnect the vacuum advance. Taught by a local TVI instructor, expert in ignition& carbs, hardcore Mopar.
IIRC we limited the mechanical to 12* in distributor(24 crank degrees), and then used about 8,10 or 12 static.
 
Last edited:
If interested in quickening your advance curve, Halifaxhops has a stash of old Mopar performance springs that should work well. i got a couple sets but haven’t had a chance to install one yet. They are in a mopar performance parts blister pack.
 
If you remove the cam, or clean off grease, either on top or underneath will be a number stamp. That would be distributor advance. 10 would add 20 degree mechanical at the crankshaft. What you could measure with timing light. Distributor turns half the speed of the crankshaft. By the 70s emission years most of those are stamped 15. Which means 30 total mechanical at high rpm. You service manual would tell you all the specs you need in chapter 8.
 
If you remove the cam, or clean off grease, either on top or underneath will be a number stamp. That would be distributor advance. 10 would add 20 degree mechanical at the crankshaft. What you could measure with timing light. Distributor turns half the speed of the crankshaft. By the 70s emission years most of those are stamped 15. Which means 30 total mechanical at high rpm. You service manual would tell you all the specs you need in chapter 8.
Thank you. Good information.
 
Auto Transport Service
Back
Top