(I think) Timing chain issue... might explain dyno/starting/timing issues..

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food for thought: I just set the tune on my 66. it has TW heads, rpm air gap intake, and .530 230 dur cam. Mine liked a lot of timing. 38 degrees at 3600 rpm with vac advance off. I connected my vac advance to manifold vacuum and it has 42 degrees at idle. I took an engines class and found out why the motor prefers that kind of timing at idle, and I decided it was okay and safe for me to run that much. it smoothed my idle out a bunch. with vac adv disconnected, my initial timing was 20 deg
 
haven't had much time recently... made an offer on a house last week (very, very busy week heh) and spent the weekend backpacking in yosemite. while i was gone my dad put the carb back on (after we messed with the floats and jets recently) and its ready to be fired up, again. no real reason to expect any change though.

we're using an old sears timing light... it isn't a particularly nice one but has worked on about 30 other engines my dad has used it on.

Posted by mrmustangman357
food for thought: I just set the tune on my 66. it has TW heads, rpm air gap intake, and .530 230 dur cam. Mine liked a lot of timing. 38 degrees at 3600 rpm with vac advance off. I connected my vac advance to manifold vacuum and it has 42 degrees at idle. I took an engines class and found out why the motor prefers that kind of timing at idle, and I decided it was okay and safe for me to run that much. it smoothed my idle out a bunch. with vac adv disconnected, my initial timing was 20 deg

I'll mess around with that tonight and try to see if i can get it do the same. Can you go into why its okay to have so much initial timing? I've always heard and read that 10-14 is where you want to be for damn near any street motor, and I've been pretty conservative because I've had detonation issues on other engines in the past.
 
Good news :D (and yes, I should be riding the short bus to work for the next month...)

I had noted to my dad that after re-stabbing the distributor, if anything the timing nonsense got worse. While I was gone in yosemite, my dad restabbed the distributor 2 teeth over and also moved the spark plugs back to their original places...

We fire it up and the initial timing at 800 rpm is... drumroll... 21 degrees!!! Almost into ideal territory!

Apparently while we were mixing and matching restabbing the distributor in various places and moving the wires the first few times, we missed this combo.

I just did some more adjustment and right now its at 18 degrees, and total timing is about 40ish. Still a little more than I'd like and its 'all in' a bit early (3000 rpm or so), so more tinkering is required but it seems much more on the right track now. Starts right up, sounds better, moves out better... ahhhhhhhhh such a good feeling.

Thanks for all those who followed this thread so closely, I learned a s***load personally.
 
Well, the important thing is that it's fixed. I'm not going to give you too much grief here........

Take good notes on the trans swap as well!! That is a project I should be doing twice this summer myself, as soon as i get back.......