Alfa Romeo Forums banner

1 - 14 of 14 Posts

·
Premium Member
Joined
·
21,359 Posts
Discussion Starter #1
A friend's 74 Spider with stock Marelli points distributor seems to advance to quickly and too far. I'm figuring the advance springs have gotten weak. Anyone know if new/good ones are available? Thanks for any leads.

Andrew
 

·
Premium Member
Joined
·
21,359 Posts
Discussion Starter #5
They are normally mismatched; you have one heavy and one light spring on the same dist.
Andrew
 

·
Premium Member
Joined
·
13,482 Posts
Andrew:
I asked the same question a while ago and got no response. The weaker of the two springs is loose in my distributor and it causes erratic idling. I would like to replace this spring with a slightly shorter one.

The Shankle re-curved Marelliplex distributors use non-standard springs to get a more aggressive curve. John must have found a source. Also, Jim Steck re-curves distributors but he may not want to share his source of parts.

Ed Prytherch
 

·
Registered
Joined
·
4,158 Posts
From an old, old, Alfa Owner. Replace the lighter MarelliPlex spring with one from A Crysler Hemi 4bl carb secondary. It was a teeny little spring, about half or less as thick as the MarelliPlex. This gave an "all in" advance at about 3K.

Caveat: This info is from the dim recesses of my memory. I think one of the MarelliPlex springs was smaller than the other, but I don't remember for sure and the motor w/ Distrubutor is in storage.

Speed shops used to sell advance springs in different sizes. I used to see advance spring kits for sale. Don't know if they're still avaliable, but you could try different springs until you find one that you liked.
 

·
Registered
Joined
·
265 Posts
Maybe 7 years ago, I got a set from AR Ricambi. I know that business has been through many changes, and don't even know if they're still around, though. Might be worth checking.

Or, maybe try an older Bosch, like an 041, 044, 045. My '74 Spica Spider really runs great with an 041, although I'm currently experimenting with a different system using an 044.
 

·
Premium Member
Joined
·
13,482 Posts
I spent a lot of time screwing around with Marelliplex distributor springs and was never satisfied with the results. I broke down and bought a 123ignition electronic distributor from IAP and I am very happy with it. I have run the standard Bosch "06" curve which is very slow and lets the engine idle at 600 rpm. I currently use the Shankle curve that makes more mid range power and gives better mpg, but the idle is a bit less stable. I plan to try another curve soon so that I can try more maximum advance without getting pinging at the low end.


Old mechanical distributors wear and get sloppy. No amount of tinkering with springs will compensate for worn parts. I am running big racing cams from AlfaR7. I would almost certainly be fighting idle problems and pinging if I still had the 'plex.
 

·
Registered
Joined
·
1,209 Posts
I have used the silver advance spring out of a NAPA distributor recurve kit part number BK 735-4448 to replace the weaker, more tightly wound advance spring in the Marelli distributor, with excellent results. About 13 bucks and you get enough silver springs to replace 2 stretched Marelli springs..
 
1 - 14 of 14 Posts
Top