Agree, done all the time on hi po /race; but can induce WOT knocking at 2k rpm or so, and higher, but factory rate is conservative. There is room. Problem with doing this is none of those “stronger springs” come with any calibration. (how much stronger?) Stronger changes rate of rise (slower rise actually) so you make that up with more initial lead. Has the effect you describe. Brutal to iterate it by pulling distributor in and out , in fact impossible due to frustration, if you are honest about it. You are never sure what you really did. Need old sun distributor machine to do right. I even sent Chrysler a letter 15 years ago..their own “upgrade kit” for electronic ignition does not have an advance curve shown to you, and their kit of springs is 3-4 springs with no curve info. My reaction: Garbage. Made a little noise as they hit the trash can. Same “hi po” curve for hemi, B and A block? Garbage. After a lot of screwing around, you need about 13-15 initial , but MUST change distributor to limit internal to about 15 too, (low 30’s total, obviously no vacuum). Knowing that, still do not know what specific spring is right. Stock light spring is OK if advance limited is what I did, what I did on another engine, blocked slot travel with braze or weld . (tried screw, no room—the slot is hardened steel) Kind of related and others may have more info, the two springs are not what is often said they are. The heavy wire one really is a dead stop, (with elongated slot on one end. It stops the light one from advancing more, at maybe 3k rpm. Trying to figure this out with no info is brutal) Reminds me of all the hot rod advice that says: “recurved distributor” ; now I know lees than I did a minute ago. You need the curve! All this very general info..your mileage may vary.. PS,. Studeaker has a nice big graph of this in every service manual since at least 1950, sorted by distributor app. Even an acceptable error band is shown. Nothing from Chrysler except initial set and a few points. And 50 different distributor numbers. You cannot in general change factory initial very much without doing something with curve, or you end up too advanced at high RPM and holes in pistons at 4 grand. From: Chrysler300@xxxxxxxxxxxxxxx [mailto:Chrysler300@xxxxxxxxxxxxxxx] On Behalf Of Michael Moore mmoore8425@xxxxxxx [Chrysler300]
Mike On Jan 13, 2015, at 9:40 PM, William Huff <czbill@xxxxxxxxxx> wrote: Rather than retarding the engine's initial timing you may consider slightly increasing the strength of the mechanical advance springs. This should raise the RPM the advance begins at but still keep that off the throttle snap. __._,_.___ Posted by: "John Grady" <jkg@xxxxxxxxxxxxxxxxx> To send a message to this group, send an email to: Chrysler300@xxxxxxxxxxxxxxx To unsubscribe from this group, send an email to bob@xxxxxxxxxxxxx or go to https://groups.yahoo.com/neo/groups/all/manage/edit For list server instructions, go to http://www.chrysler300club.com/yahoolist/inst.htm For archives go to http://www.forwardlook.net/300-archive/search.htm#querylang __,_._,___ |