Thread: Just got my hands on a '68 Chevelle with a '69 396 in it...

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This is my first big block...I'm doing a tune up and can't find the idle speed settings online or the correct timing setting. I read in a few places that 8 DBTDC is correct, but she seems to like 12. I think she has a cam, and she came with a holly intake/carb setup....can anyone offer any suggestions as far as timing and idle speed? At 12 degrees, there is no misfiring or detonation and the throttle response is good....Let me know. Thanks!

You could check manifold vacuum while moving the timing, but if it liked 12,that's fine. Idle speed is also a relative number, some cams won't let you idle below 1000. You have to find what's best for your set up. Hank