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Way to go Chris -- sounds like you solved it!!!

Speaking of PCV - I decided I'd repack the 46 year old oil trap material in my valve cover. There's a trap at each end for the pcv connections. You can see how nasty the old stuff was. Put fresh steel wool in, and made some screen covers to be sure the steel wool stays inside.







 

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I have you all to thank! So promising.

I like the steel wool idea too!
 

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Big progress on redesigning my timing advance. New and old dizzies identical other than grime. The gap you see with the pin in the middle of it determines mechanical advance. The bigger the gap, the more mech advance. Because this a 78 "emissions" distributor - it's set up for a ton of mechanical advance -- 38 degrees!!! That's because initial advance was set at 0 TDC. This late burn was so idle mixture was still burning as it left the chamber and the thermal reactors burned off the unburned HCs. This minimized NOx. But TERRIBLE for performance. So the goal is to limit mechanical advance to about 18 degrees. Set initial timing to 14-16 BTDC, and then add manifold vacuum advance of 10-15 degrees on top of that. That will help performance and efficiency.

Here's the size of the gap in the stock dizzy - goal is to make the "gap" smaller by making the pin "bigger".



Here's the stock dizzy with the gap narrowed by putting a little piece of hose over the pin -- thicker pin = smaller gap = less mechanical advance.



Using the left-most line as the base for measuring angles -- factory had 19 degrees of advance at the dizzy which is 38 degrees at the crank! By experimenting with different thickness hoses over the pin -- you can see the two lines in the middle -- one results in 7 degrees at the dizzy - 14 at the crank - a bit too little mechanical. The other results in 9 degrees at the dizzy, 18 at the crank. Perfect. I measured by placing the cardboard around the rotor with a coat hanger pointer - and actually rotating the mechanical advance and marking the pointer. Then use a protractor to measure the angles. I'll check all this with a digital timing light that let's me check timing at various rpm.



Last, I'll bring the advance in at a lower rpm by completely removing the heavier spring at the bottom. Using just the lighter spring on top will all all the mech to come in earlier - hopefully in the 2800-3500 range. Timing light will show me.
 

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Once I've confirmed all this works with the old dizzy (I also transferred over the new vacuum advance canister) -- I'll modify my brand new dizzy in the same manner.
 

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Thanks to you also Bob!! I have an anniversary get away this weekend otherwise I’d have it fully retuned and driving shortly.

It will have to wait for early next week. I can’t wait to see how the street manners are!
 

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Nice work there, Michael. I’m assuming an engine swap is going to be quite a ways in the future since you are doing all this tuning work on the motor?

Chris, your car is going to run a TON better. No more hesitation at throttle tip in, no stumbling in throttle transitions, etc.

Does your car have a chip on it (was it dyno tuned)? If so, it needs to be retuned now. If that vacuum leak was present during the tune, and they tweaked any of the WOT fuel tables, that will definitely be an issue. May be pig rich at WOT.

Funny how the bad luck of simply fixing a fuel leak led to a major breakthrough on how the car runs.
 

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Scott did dyno tune it for me with my PMS InterACQ system in Kingsport at that maximum Motorsport race shop up there. I forget his shops name....

I’m hoping that the tune was done before the intake gasket slip BUT I’ll watch it and thanks for brining it up that it might need a retune.

I am decent at reading plugs so I’ll keep any eye on those to start. It has been running rich foryears as you could see from the tops of the pistons.

I am going to run a bit of power foam/sea foam thru the intake and try to burn off / clean off the other four pistons over time.

I don't remember sluggish tip in throttle conditions but ..... once I drive it if it IS different I’ll feel and remember that instantly and be able to report back here the result.

And YES i wholeheartedly agree, the problems I ran into were actually a blessing in disguise! I suspect I’ll enjoy the car much more and hopefully my wife will find it far more pleasant to drive also. In which case.... seats are again in the cards sooner after all.
 

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Have to have a different garage set up for swap. Barely room for both cars let alone a swap.

Good counsel on tune...keep eyes/ears open. I’m of the opinion that the slip likely occurred during installation. Seems unlikely once bolted up that the gasket could move much.
 

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True.

I did find it odd that the intake bolts on the slipped side were less than hand tight when I removed them.

Many odd things here. But I am glad it’s on the mend.
 

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Well, daddy's a happy camper. Cut the mounting tab off the brand new dizzy, altered the total advance and removed a spring to bring it in sooner. Was able to set initial at about 15 BTDC; total was about 34 degrees in by 3300. Vacuum advance added about 15-20 degrees at at closed/light throttle conditions. All just about perfect. Idles smoothly at 950 rpm. MUCH more responsive. Rebalanced the carbs -- still not a clue how to go about (with something other than turn them til it runs "better") setting the idle air mixture screws. But I'll crack that nut. New cap/rotor arrived today -- irony -- Bosch, made in Japan. ;) Checked valves hot -- turns out a cold .004"/.008" results in a hot .007"/.011". A tad too tight. So I set them hot to .008"/.012". My new cold set point will be .005"/.009". I cleaned and re-gapped the plugs so I could see what they looked like after the drive. I thought they looked great - especially for a 47 year old carbed car. New valve cover gasket and a set of Denso iridiums on the way -- and I'm calling it good for now. It's running really well. And - for the first time - cranked up the stereo unit in the glove box. Turns out the car has a killer stereo in it too!!!





 

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Nice. What do the ground straps on the plugs look like? I look there for timing indications.

You'll have her purring like a kitten!
 

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I pay more attention to the color of the ceramic right now Chris. Need it to be warmer ambient to check for detonation signs - although I have lots if experience racing this engine. Pretty sure the way I have the timing set up I’m good.
 

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I have complete confidence you do as well! I was asking for curiosity’s sake. :cool:
 

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It’s really tough to get a meaningful plug read (detonation) on the street. Needs to be a wide open throttle to redline and then immediately shut off motor and coast to a stop, pull plugs, read. Any runtime after the wot pull changes the plugs. I could at the track - hard pull, coast into the hot pit and pull the plugs. I’m just trying get a feel for whether the mixture is in the ball park.
 

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That’s true! I’d check my plugs at WOT for NOS use. Filled my bottle last about 13yrs ago and need to reconnect it again sometime eventually.
 

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I haven’t added a can to mine yet. I did drill a weep hole in my intercooler and most of the “stuff” drips out the bottom prior to entering the intake. A sludgy/slimy mess of typical blow by. I’ll trade the truck well before I have any issues, only has 60k on it. The plan is to trade in about two more years, will be going diesel super duty at that point.
 

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I like the flow path of the illustration. I wondered how that actually was supposed to flow.
 

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Came across that when I was researching catch cans. I'm going to add one to mine and just vent crankcase to the atmosphere (sorry Greta!). With 4 individual runners as an intake, I can't draw vacuum from a common plenum. I have to pull it from a particular cylinder. For brake booster and vacuum advance - not a problem. Has no impact on the vacuum signal for that runner when under braking - and virtually no impact at any other time. However, PCV is constantly pulling on the crankcase in what amounts to a controlled vacuum leak -- and I can see it on the gauge when I flow balance the carbs. So -- ditching PCV on mine. A 1/2" vent line from each end of the valve cover running to a catch can that's vented to atmosphere.
 
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