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poolboy

poolboy

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With nothing better to do at the moment, I checked the vacuum reading at the brake servo banjo fitting. I'm getting a fairly steady reading of 17.5 in-Hg at idle. Ol' Basil has nearly 98k showing. How does that reading sound to you guys? Any #'s you could provide for comparison? /bcforum/images/%%GRAEMLIN_URL%%/thankyousign.gif
 
Poolboy;
is that before, or after the one way check valve in line?
If it is before (IE. engine side), then it is good!!!
Dave /bcforum/images/%%GRAEMLIN_URL%%/cheers.gif
 
Hey Dave. I tapped onto a nipple on the manifold's banjo vacuum fitting. It has 2 nipples on my 74. One is for the connection to the brake servo. The other nipple is capped off because it went to the anti- run on device that I eliminated. I uncapped it and took my reading from that port with the servo vacuum line remaining attached to the other nipple and the servo unit. THANKS.
 
17 lbs. vacuum is considered good. You could fool with the carbs and ignition and try to get more but performance would drop on that age of car. Would probably lean it too much.
 
/bcforum/images/%%GRAEMLIN_URL%%/banana.gif Just an update. By the sound of the exhaust note,searching a little, I thought that I might be a little lean yet. It took less than a full turn of the idle trim screws to fully seat them with no noticeable change. So by lifting the air valves, I saw that the rear carb was still lean. A half turn of the mixture adjustment screw clockwise evened out the exhaust note AND the vacuum reading rose to a healthy 18 in-Hg.
I guess the adjustment was necessary to compensate for the cooler weather we are having down here right now.
Anyway, all is good. /bcforum/images/%%GRAEMLIN_URL%%/cheers.gif
 
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