'69 L46 timing recommendation?
Thread Starter
Le Mans Master
Joined: Oct 2004
Posts: 6,314
Likes: 508
From: South-central Missouri
'69 L46 timing recommendation?
Well, we got 'er running - seems like it is going to be healthy.
Working on my wife's 69 L46 is a return to my beginning days in this hobby - a "blast from the past", as it were. (Quite a bit different from DOHC and ECMs, etc, etc, found on "the Z". But, I digress...
Q: considering the 11:1 pistons and 93 octane pump gas, what would you experts recommend as far as initial (vacuum removed) be and what total advance is it that works w/ todays 93 octane?
Thanks in advance. OH! BTW, what would the dwell setting be?
P.
Working on my wife's 69 L46 is a return to my beginning days in this hobby - a "blast from the past", as it were. (Quite a bit different from DOHC and ECMs, etc, etc, found on "the Z". But, I digress...
Q: considering the 11:1 pistons and 93 octane pump gas, what would you experts recommend as far as initial (vacuum removed) be and what total advance is it that works w/ todays 93 octane?
Thanks in advance. OH! BTW, what would the dwell setting be?
P.
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Around 12 initial and 36 total for a ballpark (Basically your total will dictate what your initial should be to attain the 36). My 65 L79 is 11:1 and runs fine on 93 Octane. If it pings you will have to back it off a bit.
Le Mans Master
Joined: Mar 2004
Posts: 7,493
Likes: 1,501
From: Little Rock AR
Dwell is 30 degrees or .019" on a feeler guauge.
"Initial" is not the way I would set the timing. I would start with the "total timing" method and road test it from there. Keep the vacuum advance plugged and rev the engine up until the advance will go no higher and lock down the adjustment at 36 degrees advanced. You will need a dial back timing light or a mark on the damper to do this. Let us know if you need clarification on how to mark the balancer. It is much easier than most people think.
Reconnect the vacuum advance and road test. See if you need to back off the timing at all.
-Mark.
"Initial" is not the way I would set the timing. I would start with the "total timing" method and road test it from there. Keep the vacuum advance plugged and rev the engine up until the advance will go no higher and lock down the adjustment at 36 degrees advanced. You will need a dial back timing light or a mark on the damper to do this. Let us know if you need clarification on how to mark the balancer. It is much easier than most people think.
Reconnect the vacuum advance and road test. See if you need to back off the timing at all.
-Mark.
Le Mans Master
Joined: Apr 2004
Posts: 7,106
Likes: 38
From: Newark DE
I agree with the above posts.
set total timing at 36º with the vacuum can hose disconnected and plugged. Your initial will probably fall somewhere around 12º-15º.
Make sure when you set the total timing that you rev the motor high enough that the advance is all in. If you find you are up to 4,000rpm or more and it's still advancing you probably still have the stock factory springs in the distributor and you can improve performance by swapping them out for different springs to bring the total timing all in somewhere between 2500-3000rpm.
Once your total timing is set and you test drive it to make sure there is no knocking or pinging from detonation reconnect your vacuum advance and make sure it's connected to full manifold vacuum
set total timing at 36º with the vacuum can hose disconnected and plugged. Your initial will probably fall somewhere around 12º-15º.
Make sure when you set the total timing that you rev the motor high enough that the advance is all in. If you find you are up to 4,000rpm or more and it's still advancing you probably still have the stock factory springs in the distributor and you can improve performance by swapping them out for different springs to bring the total timing all in somewhere between 2500-3000rpm.
Once your total timing is set and you test drive it to make sure there is no knocking or pinging from detonation reconnect your vacuum advance and make sure it's connected to full manifold vacuum
