Timing and Vacuum
Thread Starter
Racer
Joined: May 2010
Posts: 448
Likes: 3
From: Olathe KS
Is this normal idle manifold vacuum?
I am having such a hard time keeping this thing idling... She drives, but is still dying constantly.
I tried setting the timing. 10* at idle, 36* at WOT, both with vacuum unhooked.
I am having such a hard time keeping this thing idling... She drives, but is still dying constantly.
I tried setting the timing. 10* at idle, 36* at WOT, both with vacuum unhooked.
Instructor
Joined: Apr 2013
Posts: 146
Likes: 0
Between 17-22 is normal.
If you give me a minute or 2, I was writing you a response to help you when you posted this Pic,
Marty.
Instructor
Joined: Apr 2013
Posts: 146
Likes: 0
Hey killer, I'm certainly no expert, But what I will try and do is relay some of my experiences to you as a fairly "nooby" fella to the exact world of timing.
All my knowledge gained has been through this forum and a fairly switched on engine builder I've got to know.
Firstly , I would start by saying if you haven't got a good quality Timing light, get one , these are invaluable.
I always adopt the approach sometimes your money is best spent on buying the tools needed to do a job, and learning how to use them , Instead of paying someone to fix it , and having no idea what they did.
At least your end up with some hardware at the end of it.
Just like the saying "Teach a man to fish, and he'll feed himself for life."
Anyway, don't skimp on the light buy an adjustable digital light.
Here is what I ended up buying and it is absolutely brilliant.
Equus 590 518
This allows you to check timing (adjustable) Obviously,, derrrrrrrrr.
Has , RPM digital read out, so you don't have to keep looking in to the cars tacho.
Battery, and Alternator Voltage, as well as Dwell angle.
And I'm sure it would probley do your blood pressure as well , although I haven't tried.
Well worth the Money. $$
It will allow you to adjust the strobe of the light back, to line up the "0" mark on the Crank case with the Harmonic pulley mark, thus allowing you to see exactly what the timing is on the light, with an exact number.
( if that makes sense ) as an early Case mark only goes to 9 in most cases. And if you want to go to 16, you have to guess it with a conventional light. They only set them to 3-4 originally in the late sixties to keep the emissions down.
Then by doing this you can note Static timing,
Then with Vac hooked up , allowing you to see how much is dragged in at idle.
Then , ultimately How much collectively , and at what RPM.
Now , In my case I had my Distributer spun up and set up professionally on a machine, as that was something I couldn't do.
So assuming your distributer is working well and your problem is only in adjustment this is what I would do.
My distributer was set at 20 degrees for mechanical advance, by using the right weights and springs you can adjust this with spring tensions to progressively flick out at the right RPM points.
The vac canister on my car is factory set to pull in a further 12-14 degrees .
Now, the original set up would be running ported vacuum, being only fed in as the butterflies opened up to momentarily dragging in more advance then will drop back at wide open throttle so as not to give too much advance up top.
Now, changing over to manifold vacuum, gives you the vacuum straight away at idle , as the port of which its taken off if below the closed butterflies not on top of, so its working straight away.
And in most cases a smoother nicer idle, and better fuel economy.
However the other flip side to vacuum advance still applies , so it will drop off at wide open throttle, not giving you too much up high.
So, to the set up.
(bearing in mind I use a ULP fuel here which is 98 octane)
What I do is, check all the reference points first, and write them down.
Set static timing at 14-16 degrees with the vacuum canister on the distributer disconnected with the pipe to the manifold block off with a Screw or bolt jammed up into it.
Remembering to always keep adjusting the idle to your spec idle, approx. 650 rpm in my case. for any of the timing mark checks.
Now, connect up the vacuum advance, with the car running, and it will instantly run up in RPM as it advances.
Go back and idle it back down to your 650rpm or whatever your specs are.
And check how much advance the canister has brought in , depending on the canister specs , it may have brought all in at once or partially.
In my case , I have 16 initial timing, with a further 14 at idle with vacuum, which totals 30 degrees. (at idle )
Now as I rev it up to 3200 it will advance to 50-52 degrees, another 20 from the mechanical weights.
under WOT this equate to 36 degrees as the vacuum drops back 14 degrees roughly giving me 36, which is a good figure to work on .
(I Believe).
Now , what your problem is you are running Direct manifold vacuum , but still trying to run spec static timing , that's why it wont keep running you are retarding it. (in my opinion)
I'm hoping that what I've described here is a "nooby" explanation , put in terms that if I understand , hopefully you will as well.
Please , anyone , if I'm wrong , or if you have anything further to add, which might make it clearer, don't hesitate to add to it.
Hope this helps a little , I've taken a lot from this forum , its only fair I try and give back if at all possible.
good luck mate, Marty.
All my knowledge gained has been through this forum and a fairly switched on engine builder I've got to know.
Firstly , I would start by saying if you haven't got a good quality Timing light, get one , these are invaluable.
I always adopt the approach sometimes your money is best spent on buying the tools needed to do a job, and learning how to use them , Instead of paying someone to fix it , and having no idea what they did.
At least your end up with some hardware at the end of it.
Just like the saying "Teach a man to fish, and he'll feed himself for life."
Anyway, don't skimp on the light buy an adjustable digital light.
Here is what I ended up buying and it is absolutely brilliant.
Equus 590 518
This allows you to check timing (adjustable) Obviously,, derrrrrrrrr.
Has , RPM digital read out, so you don't have to keep looking in to the cars tacho.
Battery, and Alternator Voltage, as well as Dwell angle.
And I'm sure it would probley do your blood pressure as well , although I haven't tried.
Well worth the Money. $$
It will allow you to adjust the strobe of the light back, to line up the "0" mark on the Crank case with the Harmonic pulley mark, thus allowing you to see exactly what the timing is on the light, with an exact number.
( if that makes sense ) as an early Case mark only goes to 9 in most cases. And if you want to go to 16, you have to guess it with a conventional light. They only set them to 3-4 originally in the late sixties to keep the emissions down.
Then by doing this you can note Static timing,
Then with Vac hooked up , allowing you to see how much is dragged in at idle.
Then , ultimately How much collectively , and at what RPM.
Now , In my case I had my Distributer spun up and set up professionally on a machine, as that was something I couldn't do.
So assuming your distributer is working well and your problem is only in adjustment this is what I would do.
My distributer was set at 20 degrees for mechanical advance, by using the right weights and springs you can adjust this with spring tensions to progressively flick out at the right RPM points.
The vac canister on my car is factory set to pull in a further 12-14 degrees .
Now, the original set up would be running ported vacuum, being only fed in as the butterflies opened up to momentarily dragging in more advance then will drop back at wide open throttle so as not to give too much advance up top.
Now, changing over to manifold vacuum, gives you the vacuum straight away at idle , as the port of which its taken off if below the closed butterflies not on top of, so its working straight away.
And in most cases a smoother nicer idle, and better fuel economy.
However the other flip side to vacuum advance still applies , so it will drop off at wide open throttle, not giving you too much up high.
So, to the set up.
(bearing in mind I use a ULP fuel here which is 98 octane)
What I do is, check all the reference points first, and write them down.
Set static timing at 14-16 degrees with the vacuum canister on the distributer disconnected with the pipe to the manifold block off with a Screw or bolt jammed up into it.
Remembering to always keep adjusting the idle to your spec idle, approx. 650 rpm in my case. for any of the timing mark checks.
Now, connect up the vacuum advance, with the car running, and it will instantly run up in RPM as it advances.
Go back and idle it back down to your 650rpm or whatever your specs are.
And check how much advance the canister has brought in , depending on the canister specs , it may have brought all in at once or partially.
In my case , I have 16 initial timing, with a further 14 at idle with vacuum, which totals 30 degrees. (at idle )
Now as I rev it up to 3200 it will advance to 50-52 degrees, another 20 from the mechanical weights.
under WOT this equate to 36 degrees as the vacuum drops back 14 degrees roughly giving me 36, which is a good figure to work on .
(I Believe).
Now , what your problem is you are running Direct manifold vacuum , but still trying to run spec static timing , that's why it wont keep running you are retarding it. (in my opinion)
I'm hoping that what I've described here is a "nooby" explanation , put in terms that if I understand , hopefully you will as well.
Please , anyone , if I'm wrong , or if you have anything further to add, which might make it clearer, don't hesitate to add to it.
Hope this helps a little , I've taken a lot from this forum , its only fair I try and give back if at all possible.
good luck mate, Marty.
Last edited by martaroony; Jul 31, 2013 at 03:19 AM. Reason: Added more text.
Thread Starter
Racer
Joined: May 2010
Posts: 448
Likes: 3
From: Olathe KS
Thanks Marty -
I'm starting to wrap my head around how this all works now. The timing gun I borrowed from a friend does have the dial back, but not digital, and doesn't tell me RPM's (which would be really helpful since I don't have a tach hooked up). I have and electronic output distributor (not sure why), and the original tach (which DOES still work, but needs a mechanical distributor).
My biggest problem right now I think is getting the d@mn car to idle smooth enough to set the timing accurately. At idle, it bounces between 8-12*, but hovers more at 10* right now (vacuum unhooked). It is that low because I set the highest point while revving to 36*. Once I hooked up the vacuum I was reading 52-ish* while revving.
I'll see about buying a better gun tonight and giving it another shot, possibly using ported vacuum instead?
If anyone has suggestions on what to set my timing using manifold vacuum please chime in! I will likely have my head under the hood in 8 hours when I get off work! Thanks!
I'm starting to wrap my head around how this all works now. The timing gun I borrowed from a friend does have the dial back, but not digital, and doesn't tell me RPM's (which would be really helpful since I don't have a tach hooked up). I have and electronic output distributor (not sure why), and the original tach (which DOES still work, but needs a mechanical distributor).
My biggest problem right now I think is getting the d@mn car to idle smooth enough to set the timing accurately. At idle, it bounces between 8-12*, but hovers more at 10* right now (vacuum unhooked). It is that low because I set the highest point while revving to 36*. Once I hooked up the vacuum I was reading 52-ish* while revving.
I'll see about buying a better gun tonight and giving it another shot, possibly using ported vacuum instead?
If anyone has suggestions on what to set my timing using manifold vacuum please chime in! I will likely have my head under the hood in 8 hours when I get off work! Thanks!
Instructor
Joined: Apr 2013
Posts: 146
Likes: 0
Thanks Marty -
I'm starting to wrap my head around how this all works now. The timing gun I borrowed from a friend does have the dial back, but not digital, and doesn't tell me RPM's (which would be really helpful since I don't have a tach hooked up). I have and electronic output distributor (not sure why), and the original tach (which DOES still work, but needs a mechanical distributor).
My biggest problem right now I think is getting the d@mn car to idle smooth enough to set the timing accurately. At idle, it bounces between 8-12*, but hovers more at 10* right now (vacuum unhooked). It is that low because I set the highest point while revving to 36*. Once I hooked up the vacuum I was reading 52-ish* while revving.
I'll see about buying a better gun tonight and giving it another shot, possibly using ported vacuum instead?
If anyone has suggestions on what to set my timing using manifold vacuum please chime in! I will likely have my head under the hood in 8 hours when I get off work! Thanks!
I'm starting to wrap my head around how this all works now. The timing gun I borrowed from a friend does have the dial back, but not digital, and doesn't tell me RPM's (which would be really helpful since I don't have a tach hooked up). I have and electronic output distributor (not sure why), and the original tach (which DOES still work, but needs a mechanical distributor).
My biggest problem right now I think is getting the d@mn car to idle smooth enough to set the timing accurately. At idle, it bounces between 8-12*, but hovers more at 10* right now (vacuum unhooked). It is that low because I set the highest point while revving to 36*. Once I hooked up the vacuum I was reading 52-ish* while revving.
I'll see about buying a better gun tonight and giving it another shot, possibly using ported vacuum instead?
If anyone has suggestions on what to set my timing using manifold vacuum please chime in! I will likely have my head under the hood in 8 hours when I get off work! Thanks!
I don't want to confuse the issue here with you , but the advise I have given you was on the basis that every thing else was adjusted and working :eg carby ,( idle screws set,) spark plugs ,(right Type and Temp), Plug leads in good working order, and no other Vacuum leaks .
So all these being in good working order, the timing should be fairly straight forward.
Now I have had plug problems at idle, due to fowling plugs from to colder plug , with too shorter electrode not protruding into the chamber far enough.
Also go right through all your leads, checking their on the plug nipples fully, checking they are all earthed assuming their stainless braided.
And check under the Dissy shielding ( if you have it ) Making sure the earthing isn't to close to the coil ( - and + ) poles.
Just a general check over.
As, if your timing is jumping around 4 degrees at idle then it sounds like a miss fire somewhere down low.
I have found that if the timing is to retarded, the idle will be a Pig, and keeping it running when warm can be a bastard.
I think the best thing you can do is invest in a good light first, with the features I described, then start noting all the reference points down.
Mate , I know its frustrating, and let me tell you , I've been there.
But if your methodical, and take the advise on this forum , you will get to the bottom of it.
Hang in there, it might just take time with the forum correspondence.
marty.
Racer
Joined: Feb 2013
Posts: 269
Likes: 7
From: carpentersville ill.
light
Hey killer, I'm certainly no expert, But what I will try and do is relay some of my experiences to you as a fairly "nooby" fella to the exact world of timing.
All my knowledge gained has been through this forum and a fairly switched on engine builder I've got to know.
Firstly , I would start by saying if you haven't got a good quality Timing light, get one , these are invaluable.
I always adopt the approach sometimes your money is best spent on buying the tools needed to do a job, and learning how to use them , Instead of paying someone to fix it , and having no idea what they did.
At least your end up with some hardware at the end of it.
Just like the saying "Teach a man to fish, and he'll feed himself for life."
Anyway, don't skimp on the light buy an adjustable digital light.
Here is what I ended up buying and it is absolutely brilliant.
Equus 590 518
This allows you to check timing (adjustable) Obviously,, derrrrrrrrr.
Has , RPM digital read out, so you don't have to keep looking in to the cars tacho.
Battery, and Alternator Voltage, as well as Dwell angle.
And I'm sure it would probley do your blood pressure as well , although I haven't tried.
Well worth the Money. $$
It will allow you to adjust the strobe of the light back, to line up the "0" mark on the Crank case with the Harmonic pulley mark, thus allowing you to see exactly what the timing is on the light, with an exact number.
( if that makes sense ) as an early Case mark only goes to 9 in most cases. And if you want to go to 16, you have to guess it with a conventional light. They only set them to 3-4 originally in the late sixties to keep the emissions down.
Then by doing this you can note Static timing,
Then with Vac hooked up , allowing you to see how much is dragged in at idle.
Then , ultimately How much collectively , and at what RPM.
Now , In my case I had my Distributer spun up and set up professionally on a machine, as that was something I couldn't do.
So assuming your distributer is working well and your problem is only in adjustment this is what I would do.
My distributer was set at 20 degrees for mechanical advance, by using the right weights and springs you can adjust this with spring tensions to progressively flick out at the right RPM points.
The vac canister on my car is factory set to pull in a further 12-14 degrees .
Now, the original set up would be running ported vacuum, being only fed in as the butterflies opened up to momentarily dragging in more advance then will drop back at wide open throttle so as not to give too much advance up top.
Now, changing over to manifold vacuum, gives you the vacuum straight away at idle , as the port of which its taken off if below the closed butterflies not on top of, so its working straight away.
And in most cases a smoother nicer idle, and better fuel economy.
However the other flip side to vacuum advance still applies , so it will drop off at wide open throttle, not giving you too much up high.
So, to the set up.
(bearing in mind I use a ULP fuel here which is 98 octane)
What I do is, check all the reference points first, and write them down.
Set static timing at 14-16 degrees with the vacuum canister on the distributer disconnected with the pipe to the manifold block off with a Screw or bolt jammed up into it.
Remembering to always keep adjusting the idle to your spec idle, approx. 650 rpm in my case. for any of the timing mark checks.
Now, connect up the vacuum advance, with the car running, and it will instantly run up in RPM as it advances.
Go back and idle it back down to your 650rpm or whatever your specs are.
And check how much advance the canister has brought in , depending on the canister specs , it may have brought all in at once or partially.
In my case , I have 16 initial timing, with a further 14 at idle with vacuum, which totals 30 degrees. (at idle )
Now as I rev it up to 3200 it will advance to 50-52 degrees, another 20 from the mechanical weights.
under WOT this equate to 36 degrees as the vacuum drops back 14 degrees roughly giving me 36, which is a good figure to work on .
(I Believe).
Now , what your problem is you are running Direct manifold vacuum , but still trying to run spec static timing , that's why it wont keep running you are retarding it. (in my opinion)
I'm hoping that what I've described here is a "nooby" explanation , put in terms that if I understand , hopefully you will as well.
Please , anyone , if I'm wrong , or if you have anything further to add, which might make it clearer, don't hesitate to add to it.
Hope this helps a little , I've taken a lot from this forum , its only fair I try and give back if at all possible.
good luck mate, Marty.
All my knowledge gained has been through this forum and a fairly switched on engine builder I've got to know.
Firstly , I would start by saying if you haven't got a good quality Timing light, get one , these are invaluable.
I always adopt the approach sometimes your money is best spent on buying the tools needed to do a job, and learning how to use them , Instead of paying someone to fix it , and having no idea what they did.
At least your end up with some hardware at the end of it.
Just like the saying "Teach a man to fish, and he'll feed himself for life."
Anyway, don't skimp on the light buy an adjustable digital light.
Here is what I ended up buying and it is absolutely brilliant.
Equus 590 518
This allows you to check timing (adjustable) Obviously,, derrrrrrrrr.
Has , RPM digital read out, so you don't have to keep looking in to the cars tacho.
Battery, and Alternator Voltage, as well as Dwell angle.
And I'm sure it would probley do your blood pressure as well , although I haven't tried.
Well worth the Money. $$
It will allow you to adjust the strobe of the light back, to line up the "0" mark on the Crank case with the Harmonic pulley mark, thus allowing you to see exactly what the timing is on the light, with an exact number.
( if that makes sense ) as an early Case mark only goes to 9 in most cases. And if you want to go to 16, you have to guess it with a conventional light. They only set them to 3-4 originally in the late sixties to keep the emissions down.
Then by doing this you can note Static timing,
Then with Vac hooked up , allowing you to see how much is dragged in at idle.
Then , ultimately How much collectively , and at what RPM.
Now , In my case I had my Distributer spun up and set up professionally on a machine, as that was something I couldn't do.
So assuming your distributer is working well and your problem is only in adjustment this is what I would do.
My distributer was set at 20 degrees for mechanical advance, by using the right weights and springs you can adjust this with spring tensions to progressively flick out at the right RPM points.
The vac canister on my car is factory set to pull in a further 12-14 degrees .
Now, the original set up would be running ported vacuum, being only fed in as the butterflies opened up to momentarily dragging in more advance then will drop back at wide open throttle so as not to give too much advance up top.
Now, changing over to manifold vacuum, gives you the vacuum straight away at idle , as the port of which its taken off if below the closed butterflies not on top of, so its working straight away.
And in most cases a smoother nicer idle, and better fuel economy.
However the other flip side to vacuum advance still applies , so it will drop off at wide open throttle, not giving you too much up high.
So, to the set up.
(bearing in mind I use a ULP fuel here which is 98 octane)
What I do is, check all the reference points first, and write them down.
Set static timing at 14-16 degrees with the vacuum canister on the distributer disconnected with the pipe to the manifold block off with a Screw or bolt jammed up into it.
Remembering to always keep adjusting the idle to your spec idle, approx. 650 rpm in my case. for any of the timing mark checks.
Now, connect up the vacuum advance, with the car running, and it will instantly run up in RPM as it advances.
Go back and idle it back down to your 650rpm or whatever your specs are.
And check how much advance the canister has brought in , depending on the canister specs , it may have brought all in at once or partially.
In my case , I have 16 initial timing, with a further 14 at idle with vacuum, which totals 30 degrees. (at idle )
Now as I rev it up to 3200 it will advance to 50-52 degrees, another 20 from the mechanical weights.
under WOT this equate to 36 degrees as the vacuum drops back 14 degrees roughly giving me 36, which is a good figure to work on .
(I Believe).
Now , what your problem is you are running Direct manifold vacuum , but still trying to run spec static timing , that's why it wont keep running you are retarding it. (in my opinion)
I'm hoping that what I've described here is a "nooby" explanation , put in terms that if I understand , hopefully you will as well.
Please , anyone , if I'm wrong , or if you have anything further to add, which might make it clearer, don't hesitate to add to it.
Hope this helps a little , I've taken a lot from this forum , its only fair I try and give back if at all possible.
good luck mate, Marty.
Last edited by rays699; Aug 1, 2013 at 10:14 AM.
Thread Starter
Racer
Joined: May 2010
Posts: 448
Likes: 3
From: Olathe KS
killer
I don't want to confuse the issue here with you , but the advise I have given you was on the basis that every thing else was adjusted and working :eg carby ,( idle screws set,) spark plugs ,(right Type and Temp), Plug leads in good working order, and no other Vacuum leaks .
So all these being in good working order, the timing should be fairly straight forward.
Now I have had plug problems at idle, due to fowling plugs from to colder plug , with too shorter electrode not protruding into the chamber far enough.
Also go right through all your leads, checking their on the plug nipples fully, checking they are all earthed assuming their stainless braided.
And check under the Dissy shielding ( if you have it ) Making sure the earthing isn't to close to the coil ( - and + ) poles.
Just a general check over.
As, if your timing is jumping around 4 degrees at idle then it sounds like a miss fire somewhere down low.
I have found that if the timing is to retarded, the idle will be a Pig, and keeping it running when warm can be a bastard.
I think the best thing you can do is invest in a good light first, with the features I described, then start noting all the reference points down.
Mate , I know its frustrating, and let me tell you , I've been there.
But if your methodical, and take the advise on this forum , you will get to the bottom of it.
Hang in there, it might just take time with the forum correspondence.
marty.
I don't want to confuse the issue here with you , but the advise I have given you was on the basis that every thing else was adjusted and working :eg carby ,( idle screws set,) spark plugs ,(right Type and Temp), Plug leads in good working order, and no other Vacuum leaks .
So all these being in good working order, the timing should be fairly straight forward.
Now I have had plug problems at idle, due to fowling plugs from to colder plug , with too shorter electrode not protruding into the chamber far enough.
Also go right through all your leads, checking their on the plug nipples fully, checking they are all earthed assuming their stainless braided.
And check under the Dissy shielding ( if you have it ) Making sure the earthing isn't to close to the coil ( - and + ) poles.
Just a general check over.
As, if your timing is jumping around 4 degrees at idle then it sounds like a miss fire somewhere down low.
I have found that if the timing is to retarded, the idle will be a Pig, and keeping it running when warm can be a bastard.
I think the best thing you can do is invest in a good light first, with the features I described, then start noting all the reference points down.
Mate , I know its frustrating, and let me tell you , I've been there.
But if your methodical, and take the advise on this forum , you will get to the bottom of it.
Hang in there, it might just take time with the forum correspondence.
marty.
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Pro
Joined: Nov 2008
Posts: 542
Likes: 3
From: Bloomfield Hills MI
to the OP - that vacuum reading is spot on. Does the needle jump around intermittently, regularly pulse or is it steady-ish? Different needle behavior indicates different symptoms. I hope this question has not already been asked/answered - can't look back at older posts when editing...easily...
Thread Starter
Racer
Joined: May 2010
Posts: 448
Likes: 3
From: Olathe KS
rays699, I have the exact same light as Marty (nice explanation on timing Marty) and a 6AL setup and do not have issues reading the timing at idle or revved. Dialback function works fine. I had posted another thread about this issue a few weeks back and for all appearances, my light works great. Can be found for cheap online.
to the OP - that vacuum reading is spot on. Does the needle jump around intermittently, regularly pulse or is it steady-ish? Different needle behavior indicates different symptoms. I hope this question has not already been asked/answered - can't look back at older posts when editing...easily...
to the OP - that vacuum reading is spot on. Does the needle jump around intermittently, regularly pulse or is it steady-ish? Different needle behavior indicates different symptoms. I hope this question has not already been asked/answered - can't look back at older posts when editing...easily...
Right now it is semi-steady - I unscrewed the idle screw on the carb to the lowest idle possible, and had to unscrew the air/fuel screws pretty far (I think) to get it to show the vacuum posted, and maintain a pretty steady reading. With any more rpm (which I don't know where it is currently) or tightness of air/fuel screws, it pulses quite a bit, and drops vacuum from 7-12 range, back and forth in a repetitive manner.
Pro
Joined: Nov 2008
Posts: 542
Likes: 3
From: Bloomfield Hills MI
Vacuum wavering at lean settings is normal. The mix screws are lightly screwed in to seat, then start at 4 turns each as a base setting, then adjust for max vacuum. Looks like you're good there. Idle quality is also affected by the carb - search for some Lars postings could help.
Keep hanging in there.
Keep hanging in there.
Thread Starter
Racer
Joined: May 2010
Posts: 448
Likes: 3
From: Olathe KS
Sigh. Took my HEI cap off.. And it looked fried.. Someone had installed the spring and contact upside down.. Here are pictures. I got a new rotor and cap kit to replace. Just one more small nightmare.
Thread Starter
Racer
Joined: May 2010
Posts: 448
Likes: 3
From: Olathe KS
Update -
Car is running.
Set initial timing to 12, and with advance hooked up (direct manifold) it idles at 32. WOT goes to 52.
Car idles at 520 rpm pulling 16 Hg from the manifold.
Still dies when stopping or barely giving gas from a stop (must "punch" it, or she sputters and dies). I have a new fuel pump to install to see if that solves my issues. What SHOULD my car be idling at?
Car is running.
Set initial timing to 12, and with advance hooked up (direct manifold) it idles at 32. WOT goes to 52.
Car idles at 520 rpm pulling 16 Hg from the manifold.
Still dies when stopping or barely giving gas from a stop (must "punch" it, or she sputters and dies). I have a new fuel pump to install to see if that solves my issues. What SHOULD my car be idling at?
Melting Slicks
Joined: Apr 2001
Posts: 2,030
Likes: 363
From: Lubbock Texas
Update -
Car is running.
Set initial timing to 12, and with advance hooked up (direct manifold) it idles at 32. WOT goes to 52.
Car idles at 520 rpm pulling 16 Hg from the manifold.
Still dies when stopping or barely giving gas from a stop (must "punch" it, or she sputters and dies). I have a new fuel pump to install to see if that solves my issues. What SHOULD my car be idling at?
Car is running.
Set initial timing to 12, and with advance hooked up (direct manifold) it idles at 32. WOT goes to 52.
Car idles at 520 rpm pulling 16 Hg from the manifold.
Still dies when stopping or barely giving gas from a stop (must "punch" it, or she sputters and dies). I have a new fuel pump to install to see if that solves my issues. What SHOULD my car be idling at?
DC
Thread Starter
Racer
Joined: May 2010
Posts: 448
Likes: 3
From: Olathe KS
Got it. I'll speed her up and see what happens!
Instructor
Joined: Apr 2013
Posts: 146
Likes: 0
Update -
Car is running.
Set initial timing to 12, and with advance hooked up (direct manifold) it idles at 32. WOT goes to 52.
Car idles at 520 rpm pulling 16 Hg from the manifold.
Still dies when stopping or barely giving gas from a stop (must "punch" it, or she sputters and dies). I have a new fuel pump to install to see if that solves my issues. What SHOULD my car be idling at?
Car is running.
Set initial timing to 12, and with advance hooked up (direct manifold) it idles at 32. WOT goes to 52.
Car idles at 520 rpm pulling 16 Hg from the manifold.
Still dies when stopping or barely giving gas from a stop (must "punch" it, or she sputters and dies). I have a new fuel pump to install to see if that solves my issues. What SHOULD my car be idling at?
I agree with DC3 your idle could be a bit low, My auto BB idles at around 700,
Indecently, what carby do you have on the car , perhaps you need to adjust the idle mixture screws, sounds like it could be a bit lean at idle, and stalling.
Is it hard to start , with out pumping the accelerator. ?
My car had the same problem of dying on me at lights, when it got warm, would run fine , and then for no reason would die when I came to a stop at traffic lights.
Turned out it was the TI module getting hot and failing.
Also, distributor didn't help, it was all outta whack.
Marty.
Instructor
Joined: Apr 2013
Posts: 146
Likes: 0
Not that you'll be speeding the idle up much, but don't forget ,keep resetting the static timing , each time you adjust the idle speed.
Cause as you increase the idle up , you'll bump up the timing, be it not much , so keep checking one against the other.
You will need to end up with the idle you want ,say 700-800, if its auto ,
with the timing you want at idle, say 12 deg.
Cause as you increase the idle up , you'll bump up the timing, be it not much , so keep checking one against the other.
You will need to end up with the idle you want ,say 700-800, if its auto ,
with the timing you want at idle, say 12 deg.