Help with timing
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Joined: Sep 2011
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From: Madeira Beach, FL
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Watch a YouTube video on points style distributor rebuild to understand the unit.
Yes a single screw in the center of the rotor holds it in place and is indexed so it can only go on one way.
2 springs are under the rotor.
As advised above change only one first and only do one thing at a time so you can back track if it causes the car to worsen.
If you can get 34-36 between 2800-3000 rpm, then your cooking with gas.
First set your dwell to 28-30 again a video is most helpful for this.
Do not introduce a new component into the mix until you get the timing correct.
The electronic ignition swap will not change anything one set up right.
You just won't have points to fiddle with and if you distributor is a little worn the electronics is not effected.
Marshal
Yes a single screw in the center of the rotor holds it in place and is indexed so it can only go on one way.
2 springs are under the rotor.
As advised above change only one first and only do one thing at a time so you can back track if it causes the car to worsen.
If you can get 34-36 between 2800-3000 rpm, then your cooking with gas.
First set your dwell to 28-30 again a video is most helpful for this.
Do not introduce a new component into the mix until you get the timing correct.
The electronic ignition swap will not change anything one set up right.
You just won't have points to fiddle with and if you distributor is a little worn the electronics is not effected.
Marshal
Had a 1976 L-82, 4-sp
Joined: Mar 2011
Posts: 5,338
Likes: 1,213
From: Some days your the dog and some days your the hydrant.
Royal Canadian Navy
Springs come as part of a dist'r curve kit sold by Mr. Gasket, Crane et al. Your local down under speed shop may them. The kits don't cost much.
Advanced
Joined: Jan 2017
Posts: 64
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So I opened the distributor up and this is what I found.
I have seen where others (Lars) have suggested using different springs, but this still seems odd to me to have one super strong spring, and one spring that doesn't look like it does anything. And I'm realizing that those weights should be all the way tucked in when I take a picture like this. So I ordered the Moroso spring/weight kit, it should be here tomorrow. I'm starting to think I should have just scrapped the whole dist.
But in theory, if my total is set correctly, new weights and heavy springs should lower the initial without having to re position the distributor again?
Last edited by KingpenM3; Mar 6, 2017 at 03:25 PM.
Had a 1976 L-82, 4-sp
Joined: Mar 2011
Posts: 5,338
Likes: 1,213
From: Some days your the dog and some days your the hydrant.
Royal Canadian Navy
I can't see your pic. Maybe repost it? Anyway, your initial looks a bit too high but hey, if it starts ok so be it. But your balancer may be worn and it could be a sign of slippage of the ring or some other problem, if there is one. The weights and springs only affect mech'l advance. Rotation of the dist'r affects initial only.
Advanced
Joined: Jan 2017
Posts: 64
Likes: 1
I can't see your pic. Maybe repost it? Anyway, your initial looks a bit too high but hey, if it starts ok so be it. But your balancer may be worn and it could be a sign of slippage of the ring or some other problem, if there is one. The weights and springs only affect mech'l advance. Rotation of the dist'r affects initial only.
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Thread Starter
Racer
Joined: Mar 2016
Posts: 470
Likes: 31
From: Melbourne Victoria
Watch a YouTube video on points style distributor rebuild to understand the unit.
Yes a single screw in the center of the rotor holds it in place and is indexed so it can only go on one way.
2 springs are under the rotor.
As advised above change only one first and only do one thing at a time so you can back track if it causes the car to worsen.
If you can get 34-36 between 2800-3000 rpm, then your cooking with gas.
First set your dwell to 28-30 again a video is most helpful for this.
Do not introduce a new component into the mix until you get the timing correct.
The electronic ignition swap will not change anything one set up right.
You just won't have points to fiddle with and if you distributor is a little worn the electronics is not effected.
Marshal
Yes a single screw in the center of the rotor holds it in place and is indexed so it can only go on one way.
2 springs are under the rotor.
As advised above change only one first and only do one thing at a time so you can back track if it causes the car to worsen.
If you can get 34-36 between 2800-3000 rpm, then your cooking with gas.
First set your dwell to 28-30 again a video is most helpful for this.
Do not introduce a new component into the mix until you get the timing correct.
The electronic ignition swap will not change anything one set up right.
You just won't have points to fiddle with and if you distributor is a little worn the electronics is not effected.
Marshal
I'll leave the Breakerless ignition swap to later then.
This ones for GM HEI distributors so presume I need this one?
http://www.vpw.com.au/Category/Index/163032
Actually I think this kit is for MSD distributors.
http://www.vpw.com.au/Category/Index/182692
Here's my problem, without opening the distributor, but disconnecting the vacuum advance, I got my total advance dialed in at 36 degrees. Then I tested the initial, and I was at 29.5!
So I opened the distributor up and this is what I found.
I have seen where others (Lars) have suggested using different springs, but this still seems odd to me to have one super strong spring, and one spring that doesn't look like it does anything. And I'm realizing that those weights should be all the way tucked in when I take a picture like this. So I ordered the Moroso spring/weight kit, it should be here tomorrow. I'm starting to think I should have just scrapped the whole dist.
But in theory, if my total is set correctly, new weights and heavy springs should lower the initial without having to re position the distributor again?
So I opened the distributor up and this is what I found.
I have seen where others (Lars) have suggested using different springs, but this still seems odd to me to have one super strong spring, and one spring that doesn't look like it does anything. And I'm realizing that those weights should be all the way tucked in when I take a picture like this. So I ordered the Moroso spring/weight kit, it should be here tomorrow. I'm starting to think I should have just scrapped the whole dist.
But in theory, if my total is set correctly, new weights and heavy springs should lower the initial without having to re position the distributor again?
Last edited by Corvetteoz; Mar 6, 2017 at 08:38 PM.
Racer
Joined: Oct 2015
Posts: 414
Likes: 407
From: Meadville Pennsylvania
Before you go too far hook up a hose to the vacuum advance canister and apply a vacuum to it. You can either use a pump or your mouth either method should give enough vacuum to move the advance arm. If it does not move or it seems sluggish replace it when you get the spring set. Get an adjustable can and you can dial in the advance you want. You have a solid state HEI distributor so there are no points to set and as far as I know the dwell is not adjustable. Hope this helps a little.
Jerry
Jerry
Thread Starter
Racer
Joined: Mar 2016
Posts: 470
Likes: 31
From: Melbourne Victoria
Before you go too far hook up a hose to the vacuum advance canister and apply a vacuum to it. You can either use a pump or your mouth either method should give enough vacuum to move the advance arm. If it does not move or it seems sluggish replace it when you get the spring set. Get an adjustable can and you can dial in the advance you want. You have a solid state HEI distributor so there are no points to set and as far as I know the dwell is not adjustable. Hope this helps a little.
Jerry
Jerry
I checked the dwell and it came back at 33. According to my spec sticker above the booster, it says the dwell should be set at 30 deg. Do I adjust this by turning the bolt behind the door on the front of the distributor cap, and which way also?
Last edited by Corvetteoz; Mar 7, 2017 at 02:17 AM.
Thread Starter
Racer
Joined: Mar 2016
Posts: 470
Likes: 31
From: Melbourne Victoria
Here's a couple of pics of my distributor.
I tried to adjust that screw in the above pic to change the dwell angle back to 30. It wouldn't have a bar of it. Either the dwell angle would increase to over 40 or it would be in the mid 30's range. Best I could do was adjust it back to 33. Just wondering whether the vacuum advance line needs to be plugged when adjusting this as I had it connected? I also tried your method Jerry sucking and blowing through the vacuum advance line. All I could hear was like a flange or something moving in the vacuum advance canister, nothing in the distributor moved. Not sure if I was sucking/blowing hard enough?
Speed shop down here is out of stock for the advance curve kit. Will have to source it from the States. Is this the one I'm after?
https://www.summitracing.com/int/par...928g/overview/
I tried to adjust that screw in the above pic to change the dwell angle back to 30. It wouldn't have a bar of it. Either the dwell angle would increase to over 40 or it would be in the mid 30's range. Best I could do was adjust it back to 33. Just wondering whether the vacuum advance line needs to be plugged when adjusting this as I had it connected? I also tried your method Jerry sucking and blowing through the vacuum advance line. All I could hear was like a flange or something moving in the vacuum advance canister, nothing in the distributor moved. Not sure if I was sucking/blowing hard enough?
Speed shop down here is out of stock for the advance curve kit. Will have to source it from the States. Is this the one I'm after?
https://www.summitracing.com/int/par...928g/overview/
Last edited by Corvetteoz; Mar 7, 2017 at 06:07 AM.
Racer
Joined: Oct 2015
Posts: 414
Likes: 407
From: Meadville Pennsylvania
Here's a couple of pics of my distributor.
I tried to adjust that screw in the above pic to change the dwell angle back to 30. It wouldn't have a bar of it. Either the dwell angle would increase to over 40 or it would be in the mid 30's range. Best I could do was adjust it back to 33. Just wondering whether the vacuum advance line needs to be plugged when adjusting this as I had it connected? I also tried your method Jerry sucking and blowing through the vacuum advance line. All I could hear was like a flange or something moving in the vacuum advance canister, nothing in the distributor moved. Not sure if I was sucking/blowing hard enough?
Speed shop down here is out of stock for the advance curve kit. Will have to source it from the States. Is this the one I'm after?
https://www.summitracing.com/int/par...928g/overview/
I tried to adjust that screw in the above pic to change the dwell angle back to 30. It wouldn't have a bar of it. Either the dwell angle would increase to over 40 or it would be in the mid 30's range. Best I could do was adjust it back to 33. Just wondering whether the vacuum advance line needs to be plugged when adjusting this as I had it connected? I also tried your method Jerry sucking and blowing through the vacuum advance line. All I could hear was like a flange or something moving in the vacuum advance canister, nothing in the distributor moved. Not sure if I was sucking/blowing hard enough?
Speed shop down here is out of stock for the advance curve kit. Will have to source it from the States. Is this the one I'm after?
https://www.summitracing.com/int/par...928g/overview/
The mechanical advance springs look to be very stout also. If your intent is merely to get a baseline reading as you previously stated you will not get a true reading with this setup. You will save a lot of headaches by installing the breaker less parts you have and start your tuning process from there. Just my opinion, hope it helps a little.
Jerry
Thread Starter
Racer
Joined: Mar 2016
Posts: 470
Likes: 31
From: Melbourne Victoria
The points in this dizzy look severely burnt. It is very doubtful that you will get a correct dwell reading.
The mechanical advance springs look to be very stout also. If your intent is merely to get a baseline reading as you previously stated you will not get a true reading with this setup. You will save a lot of headaches by installing the breaker less parts you have and start your tuning process from there. Just my opinion, hope it helps a little.
Jerry
The mechanical advance springs look to be very stout also. If your intent is merely to get a baseline reading as you previously stated you will not get a true reading with this setup. You will save a lot of headaches by installing the breaker less parts you have and start your tuning process from there. Just my opinion, hope it helps a little.
Jerry
In regards to the dwell angle, does this get deleted once the breakerless ignition is installed. I'm showing my noviceness here I know
Melting Slicks
Joined: Oct 2012
Posts: 2,156
Likes: 273
From: Dunedin NZ.
Your distributor is very rusty, do the centrifugal advance weights move freely? They don't look fully retracted in the picture and this would mean the ignition advance will be too far at low rpm. I tried a spring kit a while back and the only one available here, can't remember the name off hand Mr Gasket maybe? The springs were too light and I could not get the curve I wanted, I ended up ordering a set of stock springs that were much better. I believe a lot of the spring kits are for non points ignition distributors so don't work that well in a points type distributor where you have more drag on the advance. FWIW I ended up changing to an electronic system with customisable advance curve and a pertronix module to replace the points.
Thread Starter
Racer
Joined: Mar 2016
Posts: 470
Likes: 31
From: Melbourne Victoria
Here's a couple of pics of my distributor.
I tried to adjust that screw in the above pic to change the dwell angle back to 30. It wouldn't have a bar of it. Either the dwell angle would increase to over 40 or it would be in the mid 30's range. Best I could do was adjust it back to 33. Just wondering whether the vacuum advance line needs to be plugged when adjusting this as I had it connected? I also tried your method Jerry sucking and blowing through the vacuum advance line. All I could hear was like a flange or something moving in the vacuum advance canister, nothing in the distributor moved. Not sure if I was sucking/blowing hard enough?
Speed shop down here is out of stock for the advance curve kit. Will have to source it from the States. Is this the one I'm after?
https://www.summitracing.com/int/par...928g/overview/
I tried to adjust that screw in the above pic to change the dwell angle back to 30. It wouldn't have a bar of it. Either the dwell angle would increase to over 40 or it would be in the mid 30's range. Best I could do was adjust it back to 33. Just wondering whether the vacuum advance line needs to be plugged when adjusting this as I had it connected? I also tried your method Jerry sucking and blowing through the vacuum advance line. All I could hear was like a flange or something moving in the vacuum advance canister, nothing in the distributor moved. Not sure if I was sucking/blowing hard enough?
Speed shop down here is out of stock for the advance curve kit. Will have to source it from the States. Is this the one I'm after?
https://www.summitracing.com/int/par...928g/overview/
Your distributor is very rusty, do the centrifugal advance weights move freely? They don't look fully retracted in the picture and this would mean the ignition advance will be too far at low rpm. I tried a spring kit a while back and the only one available here, can't remember the name off hand Mr Gasket maybe? The springs were too light and I could not get the curve I wanted, I ended up ordering a set of stock springs that were much better. I believe a lot of the spring kits are for non points ignition distributors so don't work that well in a points type distributor where you have more drag on the advance. FWIW I ended up changing to an electronic system with customisable advance curve and a pertronix module to replace the points.
Last edited by Corvetteoz; Mar 7, 2017 at 05:05 PM.
Advanced
Joined: Jan 2017
Posts: 64
Likes: 1