Thread: New ZZ454 and parts, engine bog?

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My ZZ430 was doing the same thing, and I found that the electric choke wasn't working worth a darn. Since the weather's warm here, I cranked it pretty much wide open, and the bog/hesitation went away.

Also, have you checked your fuel pump shot? You should get a squirt even with a tiny bit of linkage travel.

this is from holleys question section, i also think the fuel pressure is a tad high @ 7 lbs, 6 lbs is a more realistic number for the set up.
i can remove my fuel line and @ 6 lbs fill a 5 gallon jug in about a minute with about the same pump you have.

QUESTION I have a vacuum secondary carburetor that bogs when the secondaries come in. What will cause this?
ANSWER Bogging and hesitation are caused by the secondaries coming in too quickly. You can install a heavier secondary spring and this will prevent the secondary from coming in too soon. If the engine is sluggish in response at full throttle then the secondaries may not be opening soon enough. You will then need to go to a lighter spring. The spring kit is part number 20-13 which will have 7 different springs to fine tune with.

Thanks a bunch for the quick replies! I'll try playing with the choke when I get home from work today. If that doesn't work, I'll see about getting ahold of a fuel pressure regulator. I'm using a Summit fuel pressure gauge and I've heard they aren't necessarily the most accurate, but being able to adjust the fuel pressure was something I thought about setting up anyway. Again, I appreciate the advice!