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A few more tuning questions?
#11
do you have vacuum at the ported/timed vacuum port at idle?

do you have a heat insulator under the carb?

unless you are drag racing it, the first thing i would do is set the gas level in the carb so it is just below the inspection holes or near the bottom of the clear site windows immediately after you turn the engine off . having it much higher than this can sometimes cause hard starts when it is hot.

for a quick test for idle timing only, you can plug the vacuum advance then warm the engine up and let it idle as low as possible, then advance the timing 4 degrees and listen to the rpm or watch it on a tach . if it goes, up noticeably and still runs smoothly, it prefers that timing setting.

if it went up, reset the idle speed then advance it 2 more degrees, if you get the same results, it prefers that timing setting although the increase in rpm should be less.

if the engine turns over more slowly at any time, you can reduce the timing slightly until it turns over normally or get a timing delay unit . some people choose to connect the dist vacuum to manifold vacuum instead which can work if the vacuum can is properly set but i prefer the other methods.

i just saw jeffs post . using a vacuum gauge for idle timing also works . the more tools the better.
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#12
The important thing that needs to be realized when making any modifications to an engine is that the standard idle and timing specs most likely will no longer work. Even a different intake or adding headers will change things. Changing cams and compression will make even bigger changes.

What now works for a similar engine will likely not work for yours. For those of us that have been around this stuff for a while it has become second nature to adjust, readjust, and adjust again until we find that sweet spot for that particular engine combination of parts, not to mention transmission type and rear end gearing. Don't count on finding the ideal settings the first time, or maybe even the tenth time. After you drive it you'll want to improve the way it runs off the line, or at a certain cruising speed, or driving down the street. There will be compromises, the more modified the engine is, the more you will have to compromise.

Bottom line, get used to making changes Smile



“If you can't explain it simply, you don't understand it well enough.”
--Albert Einstein
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#13
Thanks Guys!! Sounds like I have a lot of stuff to try!!! Will keep you posted!!
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#14
The method I use for adjusting hydraulic lifters is simple. The lifter has to be on the base circle of that particular lobe. 1 full rotation of the crank after max lift on that particular lobe is a sure way to be on the base circle. With the rocker slightly loose, spin the push rod between two fingers. Slowly tighten the adjusting nut until you feel a slight change in the feel of the pushrod spinning. That's the zero lash position. Try it a few times to get a good feeling for it. After you've established zero lash, turn the nut the appropriate amount to achieve the specified preload and tighten the lock screw. As barnett said, the # of turns on the adjuster will be based on the thread pitch of your rocker studs. You should have 7/16-20 threads, so each turn will give .050" of preload. Typical is .020-.030, which would be 1/2 turn, but your lifter paperwork should specify.
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#15
Don C;262078 Wrote:The important thing that needs to be realized when making any modifications to an engine is that the standard idle and timing specs most likely will no longer work. Even a different intake or adding headers will change things. Changing cams and compression will make even bigger changes.

What now works for a similar engine will likely not work for yours. For those of us that have been around this stuff for a while it has become second nature to adjust, readjust, and adjust again until we find that sweet spot for that particular engine combination of parts, not to mention transmission type and rear end gearing. Don't count on finding the ideal settings the first time, or maybe even the tenth time. After you drive it you'll want to improve the way it runs off the line, or at a certain cruising speed, or driving down the street. There will be compromises, the more modified the engine is, the more you will have to compromise.

Bottom line, get used to making changes Smile

So, so, true ! goodpost

LOVE OF BEAUTY IS TASTE..THE CREATION OF BEAUTY IS ART
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