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Old 01-04-2013, 01:50 PM
Zerocyde Zerocyde is offline
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Basic carb question, does stuttering mean lean or rich?

When I say stuttering, what I mean is when you try to give it some gas and it acts like a person trying to talk when they need to clear their throat. That's what is called stuttering with carbs, right?

I see the issue in two spots. First is whenever I try to give it the lightest throttle I can. Like when trying to maintain a cruise speed, or when trying to go from a full stop very gently. If it give it more throttle its smooth as hell. The other time I see it is when trying to gun it in too low of a gear. Like cruising at 30mph in 4th and gunning it instead of down shifting to 3rd first like you normally would. I even get a carb backfire when doing that sometimes.

The only clue my newbie brain can think of is that both of those situations involve the manifold vacuum pressure dropping rather low. I only have about 9hg manifold vacuum, and I just recently switched from a 6.5pv to a 4.5pv. I'm pretty sure this issue started AFTER that swap, but then again, so did the cold weather, so I'm not sure which is to blame for the issue.

In case it matters: It's a basically stock, 1 year old sbc 355 with the smallest thumpr cam, much better than stock aluminium heads, Edlebrock rpm air gap intake, 650 holly DP, shortie headers.

Thanks for any help.

Last edited by Zerocyde; 01-04-2013 at 01:55 PM.
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