7747 spark tuning for newbies

[WEG1192 at aol.com]

Spent all of last week perfecting spark timing on a Jeep 360 AMC engine. 
First order of business was to get the spark table and a timing light to 
agree. After two days, did that. Then, I got the stock timing curves from a 
Jeep 360 shop manual and created three Excel spreadsheets showing vacuum 
advance, RPM advance, and the sums separately. Created a spreadsheet for 
maximum advance, medium advance, and minimum advance (the stock curves gave a 
range of advance, not a single curve). Burned 3 chips. Engine pinged badly on 
maximum chip. Engine ran well on medium chip but was down on power at low 
RPM, high map. Engine ran poorly on mimimum chip everywhere. Question, 1) 
does this mean that engines with mech distributor timing devices are hit and 
miss for getting a well running engine from the factory? 2) I noticed 
misfires on the minimum chip with less advance. I know retarded timing causes 
power loss but are misfires common? 3) My 7747 bin for the Jeep has timing 
pushing 50 deg in some areas, mostly high RPM, low MAP area. With dist set 
for 10 BTDC static, and bin set likewise, does this sound reasonable 
considering recent comments on maximum timing of 45 deg? Is there an 
un-hacked address for 42 max timing in the 7747 as in the $8D .tdf file? If 
anyone wants the spreadsheet file for duplicating stock distributor curves in 
a bin or my final 7747 bin for an AMC 360, Email off list. If there is enough 
interest, I'll upload to incoming.
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