#81  
Old 07-12-2022, 05:49 PM
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I did disconnect the 6AL, ran a test on it and it checked out great. I also pulled the plugs and found black soot build up. O-Reillys can load test the oil filled coil so I am going to verify correct( or break down ) condition next.
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  #82  
Old 07-16-2022, 08:12 AM
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Lot's of advice in this thread trying to resolve this frustrating issue.

One of my lesson's learned is the use of a correct spark plugs, and assuring they are not cracked during installation (some are very hard to access). And making sure the plug wires are seated properly on the plug and the cap. Look at the engine running in the dark to see if there is a electrical show going on of any spark ground outs.
I tried many of the fancy multi electrode, iridium, unobtainum, etc types, and my engine ran like crap. Butler steered me to use the correct plug, amazing what a difference it made.
Are you using Butler recommended NGK plugs in the correct heat range and reach, and none are "cracked" at the insulator from cocking the socket to tighten them?

And "I now have timing at 18 degrees at idle( no vacuum can on distributor) with heavy silver springs on mechanical advance". This makes me think you are not getting sufficient advance with the heavy springs, which makes the engine run like crap. I found lot's of initial (18 deg is good), with a quick advance (light springs) to 34-36 degrees all in by 2500 - 3000rpm wakes up the engine. Since spring selection in the distributor is a crap shoot, either experiment with lighter springs or have it dialed in on a distributor machine.

https://butlerperformance.com/c-1291...num-heads.html

  #83  
Old 07-16-2022, 08:32 AM
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How fast you can bring the mechanical advance in with any engine hinges on cylinder pressure and fuel octane level!
In fact there is a point with any motor where advance wise you have too much too fast and the motor is not yet pinging, but it is not gaining rpm as fast as it could either!

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  #84  
Old 07-16-2022, 12:45 PM
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The plugs installed ate Champions RC12YC . I have no problem going with the NGK plugs but wonder what heat range I would need. The plugs that were in the engine were way wrong with the shallow thread( 1/2"-5/8") and the electrode was buried inside the head. The Champions at least extend into the chamber and are clocked correctly . I also have the complete MSD kit for changing distributor advance springs / stops and lockout.

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Old 07-16-2022, 02:29 PM
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I would think the Champion Plugs are fine.

I'm really thinking the slow advance may be a key reason or at least one of the reasons your engine fall's on it's face during acceleration.
"CAR STILL BACKFIRES WITH OFF IDLE ACCELERATION." - yep, that is exactly what happens with too little and too slow timing advance!
Take action on your statement here:
"I also have the complete MSD kit for changing distributor advance springs / stops and lockout."
Try lighter springs, weights and maybe different stops. Here is a good video - info near the end esp.

https://www.summitracing.com/parts/msd-8464

  #86  
Old 07-16-2022, 06:19 PM
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Quote:
Originally Posted by West Coast GTO View Post
The plugs installed ate Champions RC12YC . I have no problem going with the NGK plugs but wonder what heat range I would need. The plugs that were in the engine were way wrong with the shallow thread( 1/2"-5/8") and the electrode was buried inside the head. The Champions at least extend into the chamber and are clocked correctly . I also have the complete MSD kit for changing distributor advance springs / stops and lockout.
Get those out of your engine. I had one of those exact plugs come apart in my bracket 455. It was all loose, in half basically but still in one piece.
I did not learn my lesson and put in some more just because I had them. Another broke in the middle of the welded electrode and went through the engine or got blown out. Porcelain was gone and the bottom half of the electrode as well.
Engine did not get hurt it seems, ran its best ever time after I put some Accel plugs in it and never looked back.

Heads have not been off the engine since. It will be an interesting tear down.

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  #87  
Old 07-16-2022, 09:49 PM
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Yep, that is the kit I bought. Will try the light springs and take Dragncar's advice and also change plugs.

Quote:
Originally Posted by Hesster1977 View Post
I would think the Champion Plugs are fine.

I'm really thinking the slow advance may be a key reason or at least one of the reasons your engine fall's on it's face during acceleration.
"CAR STILL BACKFIRES WITH OFF IDLE ACCELERATION." - yep, that is exactly what happens with too little and too slow timing advance!
Take action on your statement here:
"I also have the complete MSD kit for changing distributor advance springs / stops and lockout."
Try lighter springs, weights and maybe different stops. Here is a good video - info near the end esp.

https://www.summitracing.com/parts/msd-8464

  #88  
Old 07-16-2022, 10:07 PM
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About 30 years ago I bought a new set of spark plugs for my daily driver, it was a turbocharged 4 cylinder import. I took whatever plugs in the correct heat range they happened to have in stock at my local auto parts store and picked up some new plug wires at the same time.

The car started missing and lost power whenever it got on the boost, if I backed off the throttle it would smooth out and run normally. I just got used to driving it like that, staying out of the boost.

After a while I decided to swap out what turned out to be junk ND plugs for some NGK plugs and it was back to running like it did before.

The brand of spark plugs you use really does matter.

I haven’t heard anything good about Champion plugs other than the cool looking stickers they used to send you in the mail if you asked for them back in the ‘60s.

I’d get a set of NGK plugs in there ASAP.

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  #89  
Old 07-17-2022, 07:08 AM
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In regards to plugs David Vizard tells a interesting story of time on a dyno with a motor with a promise of big hp gains and the custom there to watch the dyno session.

The guys motor was down near 100 hp from where it should have been, so after 3 very embarrassing pulls they started to dig into what was taking place.

Now mind you the motor was running fine and able to get to its intended peak rpm, but just way down on power.

In the last minutes of near calling it a day and since the plugs where a tad on the dark side they put the plugs back in that where only run for breaking in the motor.

The next thing he new was that the missing 100 hp showed up!

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  #90  
Old 07-22-2022, 08:33 PM
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So, I changed out the plugs, went to a lighter advance spring, installed the new Brawler 850 double pumper . No more backfire, four corner adjustment responds well, and car sounds strong . Still need to fine tune as exhaust a little stinky and car still has what I would call a lean shake with timing jumping a little.
Thanks to all who have been making excellent suggestions, I really appreciate the knowledge that you all are willing to share.

  #91  
Old 07-23-2022, 06:32 AM
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Good news to hear!
Check how your new plugs look.

Many times idle stink is not from being too rich, but from being too lean!

Can you report back on what your idle vacuum is and if that is bouncing around also?

You need a good undampend vacuum gauge to make meaningful idle vacuum readings.

If you gauge is too dampened you may miss a dip in vacuum that allows the power valve to open or if the carb has a power piston that will pop up.

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  #92  
Old 07-23-2022, 01:14 PM
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I will pull the plugs today, have not drove the car around yet. I have 12-13 inches of vacuum at idle but that is not steady( rapidly fluctuates, bounces). The power valve is a 6.5 which is supposed to be just about right for 12-13 inches of vacuum. I took a video of the engine running and exhaust but don't know how to upload a MOV file ( i phone) to this site. Timing is set at 18-20 initial ( bounces) and I have not tried to adjust more timing at idle. I did install the lightest springs in advance and that ( as well as the carb change) seems to have solved the backfire issue.

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Old 07-23-2022, 03:02 PM
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How much is your timing bouncing and how much is your rpm dipping with the changes in idle speed that you have going on?

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  #94  
Old 07-23-2022, 05:07 PM
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Timing jumps between 18 to 20 BTDC at idle after warm up. The RPMs change very slightly ( but do change) when adjusting the four corner idle screws but the only tach I have is the one on the hood so I go by the sound difference. I do have two vacuum gauges and both fluctuate consistently between 12 and 13 inches. The most noticeable difference comes when I adjust the four corner idling as reflected on the vacuum gauges with vacuum starting out at 10 inches before idle adjusting and ending with the 12-13 after I fattened up ( enriched) the settings.

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Old 08-06-2022, 12:17 AM
TRADERMIKE 2012 TRADERMIKE 2012 is offline
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[QUOTE=West Coast GTO;6350477]Well, this is really getting irritating.

I verified correct wiring order, adjusted the valves, verified cam does not have flat lobes( by the oil all over engine method), ATTEMPTED to set idle mixture on the Quadrajet idle mixture screws( and those didn't respond hardly at all) and sprayed starting fluid around carb, intake manifold at top, etc. with no change.
The good news is that the cam is not flat and the oiling system works very well.
I did note that the #3 exhaust lifter felt soft when setting zero lash and preload.



Mikes reply:

It has been my experience to set the timing Gear at 12 o'clock on both Gears on a Pontiac Engine, this I say I have only read to this particular post # 67 so far.

If you read through my posts, you will see that I have installed a 041 cam, similar to you and when this topic came up with the timing to line up the dots as chevy does or line up the dots at 12 o'clock, I was correct in my research. I find it hard to believe that the People on this forum are very knowledgeable but simply forget this fact, you are out of phase, so go back to the beginning and all will be well, soon someone will explain it better than me. Mikes 2 cents.


Last edited by TRADERMIKE 2012; 08-06-2022 at 12:44 AM.
  #96  
Old 08-06-2022, 06:45 AM
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Dont listen to what Mike has posted.

If your timing gears where set up the wrong way in regards to the dots then to get the motor to start without just backfiring. all that needs to be done is to yank the dizzy and spin the rotor around 180 degrees, and your hood to go once you retime the motor.

18 to 20 degrees of initial timing is far too much and will make the carb hard to adjust right for idle conditions.

Here’s something to shoot for in regards to timing, but in your case instead of using 10 degrees of initial I would use 12 and then reduce what the mechanical advance brings in by that same 2 degrees.

Disregard the vacuum advance for now and concentrate on getting the motor to run its best on just the initial and mechanical advance.

I can’t believe your motor even cranks over when it’s hot with 18 degrees of initial!

You should also check that when you bring the motor up to 4500 rpm that whatever total timing you have set up does not continue to increase.

Also if you have a veriable timing light these have been known to be off.
If you have a buddy with a regular one then you should first off before doing anything confirm yours with his!
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  #97  
Old 08-06-2022, 12:31 PM
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So my car has a MSD pro billet mechanical advance dizzy with no vacuum advance. It likes 18-20 degrees at start and fires up quickly. It is my understanding that there is no built-in advance on these mechanical dizzys so what is there is all there is until the mechanical weights swing and add advance. Am I wrong here?

  #98  
Old 08-06-2022, 12:49 PM
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That’s a expensive racing distributor and I think you have shot your self in the foot some with that if the car will be used mainly on the street due to it not having vacuum advance.

That being said You clearly need to read thru that MSD instructions for it again.

If it’s the 8563 model there is tons of timing adjustments that can be made inside that distributor!

I say this because of your comments about having 18 degrees of initial timing.

I think what your mistakenly taking about is the black colored limiting bushing that gives a max of 18 degrees available.

If you had 12 degrees initial then with the 18 degree limit from the bushing you would have good safe total of 30 degrees above 4000 rpm or so.

Once again your motor would not crank over hot with 18 degrees of initial timing, that is unless you have very very low cylinder pressure.

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Last edited by 25stevem; 08-06-2022 at 12:59 PM.
  #99  
Old 08-06-2022, 01:03 PM
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Yes timing will advance with rpm unless you locked it out on the Pro Billet. I know it’s popular to put light springs in the distributor but I’ve always has best luck with the heaviest MSD springs. The lighter ones start advancing under 1000rpm and cause the timing flutter you are seeing. They also aren’t heat treated like factory springs and loose some of their tension when hot which makes things worse with time.

With a performance cam and carbureted induction with no cats you’ll always have some stink at idle. It’s the nature of the beast and you’re not tuning it out. If it’s really bad and burning your eyes it’s often too lean.

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  #100  
Old 08-06-2022, 04:16 PM
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[QUOTE=TRADERMIKE 2012;6362177]
Quote:
Originally Posted by West Coast GTO View Post
Well, this is really getting irritating.

I verified correct wiring order, adjusted the valves, verified cam does not have flat lobes( by the oil all over engine method), ATTEMPTED to set idle mixture on the Quadrajet idle mixture screws( and those didn't respond hardly at all) and sprayed starting fluid around carb, intake manifold at top, etc. with no change.
The good news is that the cam is not flat and the oiling system works very well.
I did note that the #3 exhaust lifter felt soft when setting zero lash and preload.



Mikes reply:

It has been my experience to set the timing Gear at 12 o'clock on both Gears on a Pontiac Engine, this I say I have only read to this particular post # 67 so far.

If you read through my posts, you will see that I have installed a 041 cam, similar to you and when this topic came up with the timing to line up the dots as chevy does or line up the dots at 12 o'clock, I was correct in my research. I find it hard to believe that the People on this forum are very knowledgeable but simply forget this fact, you are out of phase, so go back to the beginning and all will be well, soon someone will explain it better than me. Mikes 2 cents.
When you line you timing marks up like the picture a old Motors Manual shows you are up on # 6. You can either start out with your distributor 180 out, up on # 6. Or turn the engine over one turn and have the distributor in the correct location up on #1.
Your engine does not know the difference. I run mine 180 out because I like to have a mark on the firewall where the vacuum bulb nipple (not used, mech advance only) points to where I like to run my total advance. 36 deg in my 455 with iron heads.
Some people have looked at it and tried to tell me my engine will not run right. They do not know what they are talking about.

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