123 Distributor / Setting timing Options

[DRPHIL914]

@rjames
@914_teener

after this thread got started i decided to revisit this issue on my car, being i had the height idle as well, once i used my timing light it says 1250rpm, anyway and some chatting back and forth on pm with these 2 fine gentleman, i thought i’d post my results from this weekend of testing and retuning .
I have been running the “B” curve and thought that was correct but looking back again at the book, my ‘75 diet has the 205B/021 distributor and that coincides with the “D” curve but i think either tB,C or D can be used here if you go with the retard vac line to the vac on the distributor.

while on that curve, over the past 2 years since i got the car back in the road i had an MPS fail, and had issues with getting my idle right. i have an AF meter, and i have no vac
leaks, engine has about 60k miles, i out everything new on this when i put it back in.
SO, all that said- rjames and i discussed this and looking at the programmed curves etc i decided to try C&D, reset
timing as see what worked better- i found that the B&D didn’t heel much different, and right now i am using the C , partly due to the max advance is at 3400, and it feels much stronger in the higher rpm range now. my idle is right about 850-950 depending on if my lights are on or not, it drops 100 with the current draw but is not steady and smooth- i still had an issue with idle being low for first minute upon cold start up(yes Aar is working perfect ) so i switched out my CHT to the new one from 914rubber, and this actually helped some, i could advance it some and that would help, i set timing at 22 not 27, but also i can tell you from charting my head temps that it is running cooler head temp now at this setting. maybe because it’s just a bit richer, or just the timing and advance change not sure but once warmed up it’s really right on the nose, 850 smooth
with lights on!!! yay!! one other issue, i noticed that my oil temps start to climb when it sits and idle in driveway for 20 minutes, gauge
says 230-240, wierd since i have an auxiliary oil cooler and fan , - soon ans i drove the car around the neighborhood it dropped
to 190, head temps at this same time we’re low at 240 while sitting there.
any thoughts on that???

i just wanted to share this here rather than a new thread as it pertained to what james us going on and figured it others were maybe interested and could comment.

Phil