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bikes&bowties · 02-26-2017, 08:25 PM

I have googled my fair share before asking here and I am hoping someone can give me some ideas.

To start off its a stock 454. I'm running 16 degrees initial and 32-34 total timing. It has a summit 750 carb (holley style carb). My problem is that it idles very rich, but it idle pretty smoothly at around 15 inHg. The idle mixture needles don't change anything whatsoever. Ive read a blown power valve can cause this except it will die out and wont idle, that doesn't seem to be the case. I have checked for vacuum leaks using carb cleaner and found nothing. I'm going to try again using a propane torch. Its not a rough idle though like people describe with a vacuum leak. It runs up pretty smoothly but does lack power when driving. I feel like I need to figure out my idle problem before I can worry about the rest.

02-26-2017, 08:25 PM	#1
bikes&bowties Registered User Join Date: May 2009 Location: Washington Posts: 663	Carb rich at Idle I have googled my fair share before asking here and I am hoping someone can give me some ideas. To start off its a stock 454. I'm running 16 degrees initial and 32-34 total timing. It has a summit 750 carb (holley style carb). My problem is that it idles very rich, but it idle pretty smoothly at around 15 inHg. The idle mixture needles don't change anything whatsoever. Ive read a blown power valve can cause this except it will die out and wont idle, that doesn't seem to be the case. I have checked for vacuum leaks using carb cleaner and found nothing. I'm going to try again using a propane torch. Its not a rough idle though like people describe with a vacuum leak. It runs up pretty smoothly but does lack power when driving. I feel like I need to figure out my idle problem before I can worry about the rest.