Carb Tuning Help; Running Rich!

[Twistofkain]

I got my Chimera running but it's running really rich with gas/oil blowing out the exhaust. I also notice it bogged down when I got on the throttle. Can I get some tuning suggestions from the experts?

 

[T3X]

Start with 1.25 on LSN and 1.5 on HSN. Then start with yur LSN and then your HSN. Small turns works best. Adjust one at a time ans then go from there.

 

[T3X]

Sorry forgot to mention run your truck for about 30secs after each adjustment so the engine can run acording to the change.

 

[Deluge]

The HSN and the LSN are independent. The LSN handles acceleration, so that would be where your bogging issue lies. I'm assuming you're still running the stock carb, which is like a 668. 668's tend to have a low end lag that you can't tune out, so you won't be able to get rid of it completely. I like tuning the LSN in 1/8 turn increments, and the HSN in 1/16 turn increments.

 

[Twistofkain]

Yes, stock carb. I tweaked the LSN to reduce the bogging down. Doing little increments on the HSN will get rid of the exhaust issue?

 

[Deluge]

You want to do smaller increments on the HSN because you want to slowly creep up to the perfect tune, without overshooting it and causing a lean issue. Pay attention to the plug color when tuning the HSN. Lean it out a 16th, then do a high speed run and kill the engine before it tries to idle, then pull the plug. These are common plug colors, including the color you should aim for.

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