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Carb post is a good one! On a related subject, I've read of several guys utilizing a vacume gauge to set their carb, and even using it in lieu of a timing light (or when one's not available). Whasupwidat?:
 

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At one time I found a sweet webpage that had that info, but I never wrote it down


i tape my guage to the windsheild to see whats going on. Then with the air/fuel guage i kinda get an idea of when the rods are moving to the power step.
 

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I have used this many times when a timing light isn't avail. or will not work due to non-stock equipment or just runs bad. The vac gauge should be used in a full vac. line. If one is not available the power brakeline or the trans line will work. Put the gauge in line. Adjust the idle to what sounds about right. If not sure just set to the lowest smooth sound that will not "crash" into gear with an automatic trans. The timing should be set before trying to adjust the carb. Advance it to the highest smooth reading it will achieve. Retard the timing 1 full INCH read from the gauge. Drive. If it pings retard it 1 INCH. Repeat this until it stops pinging. Now The carb can be adjusted. You may have to re-set the idle speed. Start turning the idle screws in until the engine stumbles. Turn them out until you get a high steady reading. Stop richening the mixture when the gauge reads choppy. You want these set right at the breaking point. After you do 1 side the othert will need to be done. Just keep swapping from side to side until you get the highest,most smooth reading. Should finally be done. Drive it if no pinging and running OK, if not do again. Takes a while @ first , but works!
 

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Dragman64--What rod/jet combo are you using? I have a similar combo in my 65 and I'm planning to tune it, as soon as it breaks in. Do you have insanely high vacuum too? I have like 18" at idle and 25" at 1500rpm
 

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I get about 15" at idle.
.107 sec jets, .104 main, and #241 rods (.0705 x .0475), and pink springs. I am still fiddleing with the sec jets to make it faster.

And back to the topic, when setting the idle screws i turn one side to get the highest reading, then go to the other, and back and forth.
 

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Here are some URLs that talk about carb tuning and vacuum. If you are a Chevy
or MOPAR
hater
, then you might want to pass. If your a racer or hot rodder then these might help.

http://www.centuryperformance.com/vacuum.htm
http://www.mortec.com/carbtip1.htm
http://www.allpar.com/fix/carb-tuning.html
http://www.hotrodder.com/kwkride/power.html
http://www.nastyz28.com/perftune.html


An engine is also a vacuum pump.
_________________
65 Mustang Coupe, 289 cu. in., Tri-Y header, Mallory Unilite. Going into restoration this fall, 2002.

<font size=-1>[ This Message was edited by: oils65mustang on 4/27/02 5:15am ]</font>

<font size=-1>[ This Message was edited by: oils65mustang on 4/27/02 11:38am ]</font>
 
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