massive reconfiguration time again.

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j par said:
Yes, same heat range.
Click to expand...

Then I stick to my theory. wrong heat range for the new cam and all the cylinder pressure. Not saying this is "for sure" the issue, but I'd try fattening up the carbs and running RN12YC. If it doesn't work, your out a little time and a set of plugs. BECAUSE...……. cudafever's picture is your plug, then I go back to my previous statement, it looks blistered. You may find yourself adding some performance that will be noticed by the seat of your pants
Cudafever said:
If your taking about my Post 1046, it is j par spark plug i copied it from post 1043 and added some art work.
Click to expand...
 
If it is lean, it could explain the cruise tippin stumble.
 
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Maybe I finally have leaned out too much at idle and that's affecting the cruise mode. Maybe it's one of those things where you got to give a little to get a little LOL
 
j par said:
That's been a few years since the heads were off. At that time the heads had about 9-10 months since a total rebuild. 596 heads. I took the heads off and ported for a few days (under shop instructions). They did a couple hours of touch up and put in 2.02's. Oil leaking in all 8?
I haven't heard any leaks...
Click to expand...
If the guide is leaking it will pull oil out at idle. Its not going to be enough to see smoke out the pipe, but if it is it will eventually throw a puff of blue at startup.
I don't think it is something to focus much with at this point.
 
j par said:
Maybe I finally have leaned out too much at idle and that's affecting the cruise mode. Maybe it's one of those things where you got to give a little to get a little LOL
Click to expand...
steps in the metering rods by the shape..... Don't have to give a little to get a little.....
 
Cudafever said:
AFB or AVS
Click to expand...
Edelbrock 1406 on the front and a Carter performance.
IMG_20190404_202345.jpg
 
AFBs
I have rebuilt many of them but never in depth tuning, plus the 2-4 i'm way off.
I can only speak holley,
many circuits will work the same or similar. holley power valve. afb metering rod spring weights.

How far are you off from the main jets that came in them carbs from the factory? This may give you a idea how far of you are.
Its apple to oranges when i come to the front main jets as there is a metering rod that has a major effect on cruise jet size.

I think i would put a smaller ............
someone that tunes these AFB need to chime in. i could say something that easily make sence but it just not the truth when it come to a AFB.:(
 
j par said:
These are my thoughts as well and if the AF gauge is correct that would explain it's reading a quick lean than a plumit to 11 something than back up..?
Click to expand...

No i think it when lean for a slit sec because you metering rod was shaped wrong or the spring was not stiff enough and it when lean then the metering rod raised up and richen it up.
 
j par said:
View attachment 1715363798 that's the best picture of after the long drive...
Click to expand...
The only thing that show me is that you don't have a coolant leak, that has steam cleaning the piston top.
have you redone a compression check now your back(one again not real important for the problem you're trying to fix)
Piston top or spark plugs won't tell you much at idle. no heat to burn off the carbon.
 
318willrun said:
Then I stick to my theory. wrong heat range for the new cam and all the cylinder pressure. Not saying this is "for sure" the issue, but I'd try fattening up the carbs and running RN12YC. If it doesn't work, your out a little time and a set of plugs. BECAUSE...……. cudafever's picture is your plug, then I go back to my previous statement, it looks blistered. You may find yourself adding some performance that will be noticed by the seat of your pants
Click to expand...
Hey 318willrun! I was just about to agree with you, then I realized it was ME! LOL...
 
Cudafever said:
AFBs
I have rebuilt many of them but never in depth tuning, plus the 2-4 i'm way off.
I can only speak holley,
many circuits will work the same or similar. holley power valve. afb metering rod spring weights.

How far are you off from the main jets that came in them carbs from the factory? This may give you a idea how far of you are.
Its apple to oranges when i come to the front main jets as there is a metering rod that has a major effect on cruise jet size.

I think i would put a smaller ............
someone that tunes these AFB need to chime in. i could say something that easily make sence but it just not the truth when it come to a AFB.:(
Click to expand...
As you can imagine I've been messing with these carbs for years.
I'm still trying to keep it simple.
I've been trying to work that idle up to a 14-7. I'm pretty sure I went up to the 75/47 earring rods as the 71/47 are in their case.
I'm starting to think throw the 7147 is back in and turn my timing back up a couple of degrees and test on freeway?
IMG_20190715_082743.jpg
IMG_20190715_083019.jpg

Almost positive that I cracked this number 3 spark plug when I was taking it off after the trip but it seemed to be burning proper like the rest so I changed it to pull the car back in with its old plug. I plan on buying a new plug but it would also be kind of a good experiment to see if it turns the plug a different color?
 
Then I stick to my theory. wrong heat range for the new cam and all the cylinder pressure. Not saying this is "for sure" the issue, but I'd try fattening up the carbs and running RN12YC. If it doesn't work, your out a little time and a set of plugs. BECAUSE...……. cudafever's picture is your plug, then I go back to my previous statement, it looks blistered. You may find yourself adding some performance that will be noticed by the seat of your pants
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
I really think this should be your first step. back to the basic.
known good stockesh plugs, stock jets and metering rods.
run test and then re read plugs.

Remember this is not a stock cam and neither was your last one. There will be reverso(exhaust gas into the clean Air/fuel at idle) that will fool you on the spark plug read.
You need to take it on a good cruise and pull over and look at your plugs. need to drive it long enough to burn of all the evidence of the idle vision.
 
j par said:
As you can imagine I've been messing with these carbs for years.
I'm still trying to keep it simple.
I've been trying to work that idle up to a 14-7. I'm pretty sure I went up to the 75/47 earring rods as the 71/47 are in their case.
I'm starting to think throw the 7147 is back in and turn my timing back up a couple of degrees and test on freeway?
View attachment 1715363810 View attachment 1715363811
Almost positive that I cracked this number 3 spark plug when I was taking it off after the trip but it seemed to be burning proper like the rest so I changed it to pull the car back in with its old plug. I plan on buying a new plug but it would also be kind of a good experiment to see if it turns the plug a different color?
Click to expand...

Ok so here i go sending YOU down a rabbit hole.....

On the holley the idle circuit is seperate from the rest so jet changes don't do much, just the fuel mixture screws. that same circuit controls tip in/cruise fuel. the venture is controlled by the main jets and front metering rods, in your case, power valve on the holley, controlled by vac.(and air bleeds of course).
 
Cudafever said:
Then I stick to my theory. wrong heat range for the new cam and all the cylinder pressure. Not saying this is "for sure" the issue, but I'd try fattening up the carbs and running RN12YC. If it doesn't work, your out a little time and a set of plugs. BECAUSE...……. cudafever's picture is your plug, then I go back to my previous statement, it looks blistered. You may find yourself adding some performance that will be noticed by the seat of your pants
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
I really think this should be your first step. back to the basic.
known good stockesh plugs, stock jets and metering rods.
run test and then re read plugs.

Remember this is not a stock cam and neither was your last one. There will be reverso(exhaust gas into the clean Air/fuel at idle) that will fool you on the spark plug read.
You need to take it on a good cruise and pull over and look at your plugs. need to drive it long enough to burn of all the evidence of the idle vision.
Click to expand...
Yes I think I get a lot of idle Vision LOL lot of round Town stuff if it's not flat out on the Dragstrip. Also when the RPMs are up or off the line when it is wide open it does dip down to like 11.9 and lower so I'm feeling the secondaries are close.
Okay I'm having a brain fart moment here why is it that I want a hotter plug to make the lean condition go away and make my plug stopped running so hot on the strap?
 
Cudafever said:
Ok so here i go sending YOU down a rabbit hole.....

On the holley the idle circuit is seperate from the rest so jet changes don't do much, just the fuel mixture screws. that same circuit controls tip in/cruise fuel. the venture is controlled by the main jets and front metering rods, in your case, power valve on the holley, controlled by vac.(and air bleeds of course).
Click to expand...
and that's where I get at have to give a little to get a little. I may have to give up some of that leanness at idle so it's not so lean at Cruise?
 
o2 sensor is a great tool but don't get set on a number. what the eng like, the eng likes, and that's what you should shoot for.....when you get it all sorted out.

Example you may need a richer then purfice afr at idle because of the exhaust gas reversion. what the eng like is what the eng wants.
 
Also throw this Voodoo out of my mind that I'm going to make it to Rich and wash my cylinders and ruin my engine...lol which long would have been done if that was the case...
 
j par said:
and that's where I get at have to give a little to get a little. I may have to give up some of that leanness at idle so it's not so lean at Cruise?
Click to expand...
Still rabbit holing.
More rich at idle= mixture screws (idle mixture screw) cruise is the diameter and shape of the metering rod with vac holding it in to the main jet........I think,,.....,,,...,.,.,.
 
Stop thinking you're going to make it so lean you're going to burn a hole through your piston okay I had to get those two extremes out of my head now what were we doing LOL...
Cudafever said:
Still rabbit holing.
More rich at idle+ mixture screws (idle mixture screw) cruise is the diameter and shape of the metering rod with vac holding it in to the main jet........I think,,.....,,,...,.,.,.
Click to expand...
:BangHead: lol...
 
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