Timing Questions part 2
Thread Starter
Burning Brakes
Joined: Jun 2004
Posts: 936
Likes: 0
From: Tulsa OK
Timing Questions part 2
Rather than resurrecting a week old thread, I think I'll just start a new one.
The new intake is in. While I had it out I went ahead and cleaned up the distributor as best I could and shimmed the end play. WOW was it bad. I bought a package of Mr. Gasket distributor shims (2820 I think), and after putting the entire package on, it still gapped out at .018. That's still off from the recommended .010-.012, but it's certainly better than it was to begin with.
I pulled out the shaft, cleaned up the gunk under the centrifugal plate and lubed it with a small amount of white lithium grease. So the weights will move around freely now.
Everything is back together and mostly timed. Initial is set at 18* @850RPM, total timing is 36* but it's not coming fully in until about 4-4500. I've got one silver and one black spring on. I could drop down to two black springs, but I'm not entirely sure they're strong enough to pull the weights fully back in.
So in short, the timing appears to be set to where it's supposed to be, it's just not coming fully in as early as I understand it should be. Should I just leave it alone for now?
BTW: I'd like to say thanks to Lars, BarryK and everyone else who has written tech papers and/or chimed in to help me get this far. You guys are great!
The new intake is in. While I had it out I went ahead and cleaned up the distributor as best I could and shimmed the end play. WOW was it bad. I bought a package of Mr. Gasket distributor shims (2820 I think), and after putting the entire package on, it still gapped out at .018. That's still off from the recommended .010-.012, but it's certainly better than it was to begin with.
I pulled out the shaft, cleaned up the gunk under the centrifugal plate and lubed it with a small amount of white lithium grease. So the weights will move around freely now.
Everything is back together and mostly timed. Initial is set at 18* @850RPM, total timing is 36* but it's not coming fully in until about 4-4500. I've got one silver and one black spring on. I could drop down to two black springs, but I'm not entirely sure they're strong enough to pull the weights fully back in.
So in short, the timing appears to be set to where it's supposed to be, it's just not coming fully in as early as I understand it should be. Should I just leave it alone for now?
BTW: I'd like to say thanks to Lars, BarryK and everyone else who has written tech papers and/or chimed in to help me get this far. You guys are great!
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,118
From: Crossville TN
You did disconnect [and plug] the vacuum line to the distributor??? Full advance should come in well before 4500 rpm, if you want any kind of decent performance out of the engine. Pull one spring off of one of the weights and try it again. Back off and add put your lightest weight spring to the "empty" weight side, if the engine begins to ping (pre-detonation). Get full advance to come in before 3000 rpm. At low rpm, the spring [or springs] will have no trouble bringing the weights back to rest position.
Pro
Joined: Dec 2006
Posts: 665
Likes: 0
From: wilmington nc
While your waiting on someone to recommend what to do about your timeing not being all in until 4000 rpm you can check total timeing. hook the vacume back up it shouldnt go past 52* You"ll need a vacume can that provides 16* the AR23 does a good job at providing that 16* the number should be stamped on top of the vacume can.
Thread Starter
Burning Brakes
Joined: Jun 2004
Posts: 936
Likes: 0
From: Tulsa OK
The vacuum advance is indeed disconnected and plugged.
Here's a thought. Is it possible the weights are on upside down? I took pictures during disassembly so I could put everything back the way it was, but the fact that full timing isn't coming in any sooner now than it was with far heavier springs and a gunked up and sloppy shaft could, I suppose, mean that it was put together wrong in the first place? I had assumed that if the weights were installed for counter-clockwise rotation instead of clockwise, then the spinning would draw them in tighter. But maybe not.
I guess even if I can't get the distributor to work correctly and end up buying an entire new one, I can chalk this up as a learning experience. It doesn't work any worse than it did before I took it apart. There's got to be a bright side somewhere, right?
Here's a thought. Is it possible the weights are on upside down? I took pictures during disassembly so I could put everything back the way it was, but the fact that full timing isn't coming in any sooner now than it was with far heavier springs and a gunked up and sloppy shaft could, I suppose, mean that it was put together wrong in the first place? I had assumed that if the weights were installed for counter-clockwise rotation instead of clockwise, then the spinning would draw them in tighter. But maybe not.
I guess even if I can't get the distributor to work correctly and end up buying an entire new one, I can chalk this up as a learning experience. It doesn't work any worse than it did before I took it apart. There's got to be a bright side somewhere, right?
Drifting
Joined: Mar 2006
Posts: 1,526
Likes: 2
From: Oak Ridge NC
You did disconnect [and plug] the vacuum line to the distributor??? Full advance should come in well before 4500 rpm, if you want any kind of decent performance out of the engine. Pull one spring off of one of the weights and try it again. Back off and add put your lightest weight spring to the "empty" weight side, if the engine begins to ping (pre-detonation). Get full advance to come in before 3000 rpm. At low rpm, the spring [or springs] will have no trouble bringing the weights back to rest position.
Try the lightest spring...how else will you know if it is going to work if you don't try it? Before you do, take for a vigorous ride 
so that you know you don't have detonation with the current set-up.
Tech Contributor
Joined: Aug 1999
Posts: 14,380
Likes: 6,391
From: At my Bar drinking and wrenching in Lafayette Colorado
Very possible. The HEI weights go on the opposite way from the standard points-type distributor weights. I.e., the free end of the weights point in the direction of rotation. On a points distributor, the free end of the weight is the trailing edge. If the guy before you installed them like a points-type weight and you duplicated this, then your weights are on backwards and your curve will be very slow.
Lars
Lars
Race Director
Joined: Sep 1999
Posts: 11,361
Likes: 383
From: Plano TX
The new intake is in. While I had it out I went ahead and cleaned up the distributor as best I could and shimmed the end play. WOW was it bad. I bought a package of Mr. Gasket distributor shims (2820 I think), and after putting the entire package on, it still gapped out at .018. That's still off from the recommended .010-.012, but it's certainly better than it was to begin with.
Thread Starter
Burning Brakes
Joined: Jun 2004
Posts: 936
Likes: 0
From: Tulsa OK
It's there. There just really was that much slack. There weren't any shims installed at all when I took it appart. I'm guessing that whoever the last person to work on the distributor didn't bother to put them back in.
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Thread Starter
Burning Brakes
Joined: Jun 2004
Posts: 936
Likes: 0
From: Tulsa OK
Lars rocks!
I would just like to redundantly point out that which everyone on the forum already knows:
LARS ROCKS!
After several emails back and forth trying to figure out why my timing was coming in so late, he noticed that the weights on my distributor were the crappy aftermarket replacements and pointed me to find some OE ones instead. So after raping parts from an old distributor, my initial timing is at 14* and total is 36* and coming all in by 2800 rpms. Way better than the 4500 it's been coming in at. MAN do those replacements suck. The old girl has never run so good!
The only downside was the ignition module going out right after I finished getting everything in time. But at least it went out at home in my garage instead of in a parking lot somewhere.
Once again I want to say thanks to Lars for his help and for the great tech paper and BarryK for HIS timing write-up and to everyone else that's offered their help through out this ordeal. You guys all rawk.
Have a cold one on me.
LARS ROCKS!
After several emails back and forth trying to figure out why my timing was coming in so late, he noticed that the weights on my distributor were the crappy aftermarket replacements and pointed me to find some OE ones instead. So after raping parts from an old distributor, my initial timing is at 14* and total is 36* and coming all in by 2800 rpms. Way better than the 4500 it's been coming in at. MAN do those replacements suck. The old girl has never run so good!
The only downside was the ignition module going out right after I finished getting everything in time. But at least it went out at home in my garage instead of in a parking lot somewhere.
Once again I want to say thanks to Lars for his help and for the great tech paper and BarryK for HIS timing write-up and to everyone else that's offered their help through out this ordeal. You guys all rawk.
Have a cold one on me.