NEED HELP With 2.8 tuning

[guy5979]

This is my first carbureted truck and i cant figure out if its supposed to run like it does
i did a petronix conversion though it runs the same as before
ive been trying to tune it with a vacuum gauge to no avail
please disregard my improvised vacuum plugs

heres a link to a video of it running

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[SenorNoob]

I've heard worse for sure. Does seem to be bouncing somewhat though. Missing?
What does you're vacuum gauge read? Better would be a video of the vacuum gauge in action.
Have you tried to drive it? How does it feel?
Can you read spark plugs? Or pull them and post a picture of each one with the cylinder it came from?

Maybe someone else has better information, but that give you something to check and the extra info should help stimulate conversation.

 

[MadMax_636]

First of all. That vent on the top of the carb isnt a vacuum port. Its a carb bowl vent.
Second, look for a non feedback carb. You need to them get 50 sized jets.
Third, Make sure your vacuum advanced port isnt pulling any vacuum at idle. Put a gauge on that port and lower the idle until it reads nothing. Then raise it until it reads some and back off. Make sure there is zero. You do want it to engage when getting on the throttle.
Fourth, Set your timing with both a timing light and with the vacuum gauge. A good starting mark it around 12-14 on base timing. You also want the vacuum advanced unplugged.
Fifth, For my engine. I have the idle screws 2 or 2 1/2 out.

For when you get a new carb. You want a 1.08 venturi size. Any bigger itll run lean not matter how big of jets you give it. Ask me how I know haha. Too much air for the 2.8. Great down low torque but zero top end power.