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Well tonight I took JohnPro's suggestion and re-curved the MSD carb. I had about 45 degrees total timing it seems, using the smallest (red) stop bushing and the lightest springs (silver). I changed to the blue stop bushing whihc is supposed to allow only 21 degrees of mech. advance, plus the blue springs, which is supposed to delay the arrival of all of the timing till around 3800 rpm or so. I set the initial timing at 13 degrees. Did not having anyone to rev the engine while I checked the timing for total advance so I am just hoping it is 34 degrees. I also leaned out the mixture screws by 1/4 turn, leaving 1.25 turns out as the setting. The car ran a lot better. The backfiring through the exhuast is gone, except for one pop when I turn off the ignition. I figure my valve adjustment might have gotten an exhaust valve too tight so that it doesn't completely seat. Would that give me the "pop". Also, the slight stumble with engagement of the secondaries is gone. It is not quite there yet, but closer.

ok, now for the doofus. This is unreal. I have the key in the on position cause I had been bumping the starter to line up TDC, then checking with a flashlight to see if the timing marks lined up on the pointer and balancer. As I leaned over the passenger fender to check the timing marks, the gold chain I wear fell out frum under my t shirt and shorted across the starter solenoid. WOW. gold is a pretty good conductor, I'll have to attest to that. That chain sparked and got a little warm real quick. This is about the weirdest doofus I've done, and I've done a lot.

Well, I figure raising the float level on the primary side just a wee bit and then leaning out the mixture 1/4 more turn.. Also, my idle is probably over 1000 rpm, so I need to adjust that down to around 700 or so (manual trans)., After that, a double ehck by adjusting the mixture screws for maximum vacuum and that should get me to driveability stage, with dyno tuning and re-jetting needed to get race ready,.
 

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It is easier and cheaper to just buy gold plated battery cable/solenoid ends than doing it yourself .
 
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I have to admit that was a good doofus. The charge of ignition voltage should always qualify one for an award. But thank goodness you were mostly ) unharmed and the car runs better now. By the way I looked at your website, didnt you paint that car yourself? Very nice work, I have tried a paint job once before and now I truly understand why they are so expensive ).
 

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Ken, good doofus ... ranks right up there with me hitting myself in the face with a hammer, banging on Chris's '65 when we first started that project.

Don't lean out your fuel mixture too much or you're going to cause overheating problems when idling. The idle mixture is not going to help an off idle stumble one iota. Lean mixtures burn hotter. I have to run as rich an idle mixture as I can to keep from running hot at idle.

The backfire is mostly likely due to a valve not closing. Re-adjust the valves, PRONTO, before you burn it/them.

With 21 degrees of advance, and the 2 light blue springs, your timing is all the way in by 2800 RPMs. The 3800 is if you're running a full 28 degrees of advance with the 2 light blue springs.

You going on the HAN cruise with us Saturday? If so, you and I could hook up and go up together (even car pool if you want as SWMBO will be in San Diego).
 

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Discussion Starter #5
If a valve is not closing all the way, would that not mean that I have NOT turned the adjusting screw far enough? I was thinking, if a pushrod was too long, it would not allow the valve to seat. By turning the adjusting nut in, one is, in essence, shortening the push rod. The only direction I adjusting the valves was to turn the adjusting nut in, at most, a half a turn. I had one valve that would occassionally give me that noisy rocker souind. Hence, I adjusting across the board the valves that seemed to allow the push rod to spin too easily between my fingers.

As for HAN, are you do a day trip or an overnight?

Thanks for the input.
 

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Year back I agreed to assist a friend with troubleshooting wiring problems on a '65 he was restoring. Everything went fairly well but I forgot I was wearing my Seiko Kinetic watch (metal band and bezel). Horn wire was loose and horn ring was off car. I leaned over the instrument panel attempting to check a point behind the backshell when "Zap!" My watch band contacted the horn circuitry on the column and the band got hotter then you can imagine. I exited the drivers seat in a hurry while trying to rip the watch off...it was hot and burning my wrist. A day later I noted the watch was not working right and realized I'd zapped it too ($350). I sent it off to Seiko for repair and they repaired it for free (lucky, it was out of warranty). The super capacitor inside the watch was fried from the zap. Of course its a lesson learned...take watches and jewelry off before working on cars!
 

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If a valve is not closing all the way, would that not mean that I have NOT turned the adjusting screw far enough?
No. That would mean it's adjusted too far, holding the valve open. . .

adjusting across the board the valves that seemed to allow the push rod to spin too easily between my fingers.
On a broken-in engine the pushrods always seem to spin easily, IME, since they're oiled up and worn it to the lifter and rocker arm. When I adjust mine I make sure the valve is closed, loosen the rocker, and wait maybe 30 seconds or so to let the lifter 'relax'. I then tighten the rocker until all the play is taken out of the pushrod and then go about 3/4 turns past that. The adjustment needs to be done in a timely fashion, since the lifter will want to bleed down and will feel loose if you check it a minute or so after it's adjusted. Remember to cinch the polylock down with a box end wrench while holding the set screw. You will tighten the rocker a bit further when you cinch it, which is why I said to go 'about' 3/4 turns above. If you just cinch the set screw then the rocker will likely loosen. Usually they're done at that point but if it doesn't sound right I'll run the engine and apply pressure to the rockers while it's running to see which one may be loose.

Be warned, small exhaust leaks sound an awful lot like valve tick and can make the whole process quite frustrating. Been there, done that. ::

On my engine I can usually tell what needs adjusting by wiggling the rockers on the closed valves as I rotate the crank by hand. After wiggling a few, it seems pretty obvious to me what's loose. It's totally subjective and unscientific but you might give it a try.

Glad to hear the carb is working better. What's your idle RPMs at with 0.020" of the transfer slots exposed on both butterflies?

Watch that gold, pimp daddy! ::
 
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