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Discussion Starter #1
Hope you are all having a good weekend. This question is about idle RPM. 69 302, bored 30, Holley 4bbl, edelbrock performance intake, mild+ CAM 504 lift, 284 duration. currently only stock converter. I recently installed a tach and found the car runs best in drive with an idle of 750-800 and idle in park of 1100. When i turn the idle down to 1000 in park it starts to get a little more rough and anything under 1000 is really rough and nearly stalls. I know i have to change my converter this winter. However prior to that, do you have any recommendations? Is it OK to let the car idle at 1050-1100 in park/neutral? The 750 idle in drive feels nice. Thanks for the help
 

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Discussion Starter #3
Thanks. Yes, it is a holley with only one set of mixture screws. I tuned them to max vacuum pressure off the manifold. Still unclear to me why the guy i bought the car from had such a large cam put in this street 302. To me, those specs would much better serve a track car. Am not in the mood to change out the cam though.
 

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Spammer Hammer
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If you have adjusted the idle mixture to max vacuum and set the timing appropriately, set the curb idle where the it idles best and forget it. Mine idles best around 1000-1100RPM, but it’s a bit different.
 

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When adjusting the mixture screws, its best to set the idle speed first at the factory recommended rpm (even if it barely runs) and then adjust the mixture screws. If you adjust the mixture at 1000 RPM, it will not be accurate because the throttle plate is open too far which affects the mixture. Anyway, sounds like you have it set to where you want it so, that's all that matters. I think the factory spec on mine (6 cyl.) is 600 rpm but I like it at 750 . I bump it to 800-825 in the summer when I run the AC.
 

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Discussion Starter #9
Thanks for that info. I didn't know that. Am going to re check the mixture with the idle down. thanks man
 
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