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Old 02-20-2020, 07:52 PM   #1
conoco
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Vacuum Question

My truck would die when I put it in gear and idle pretty rough. I checked the timing and it was 2 degree retarded, I just bought the truck also. I set the timing at 12 degrees advanced and it started purring and sounding great. I had the vacuum advanced unplugged when I did this also. But the idle was even better at 16-18 advanced. Is that normal or ok? I do have the 383 stroker so I didn't know if that changed from the standard 12 degree advanced like I have read. Anyone have suggestions or input?

On a side note I am looking to add the vacuum gauge to my gauge cluster. I have an open spot but can someone recommend where to plug the hose in at my carb? or does it go somewhere else? Thank you everyone.
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Old 02-20-2020, 08:48 PM   #2
Steeveedee
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Re: Vacuum Question

Once you have a higher compression(?) engine and other non-standard items like a camshaft, the factory settings will only be a guideline. If you run that much initial advance, you will need to look into limiting total advance to avoid engine damage, though. For the gauge to give meaningful readings, use manifold vacuum. If you use ported vacuum (attached to a port above the throttle plate) you will have little to no reading at idle.
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Old 02-20-2020, 11:04 PM   #3
geezer#99
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Re: Vacuum Question

Here’s some info on timing.

https://www.badasscars.com/index.cfm...&product_id=76
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Old 02-21-2020, 01:38 PM   #4
conoco
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Re: Vacuum Question

you guys are awesome! thank you for the help.
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Old 02-21-2020, 01:46 PM   #5
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Re: Vacuum Question

Quote:
Originally Posted by geezer#99 View Post
I just learned so much from that article. Thank you for sharing that. Everything makes much more sense now.
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