So I recently upgraded my non hemi 420:
Arc rod
34mm mikuni kit from GPS
TWISTER 250 CAM
50lb Valve Springs
Header
40 series CVT
I have it geared and setup so it won't rev past 4500. Once I go to the next stage up, I will get a flywheel.
I think my issue is with the carb. I've been messing with jetting and no matter how lean I go, it still appears to be rich. I'm currently at a 190 main and 12.5 pilot jet. I ordered a 10 pilot but it isn't here yet.
I've seen people run these on stock engines so I'm very confused as to why I am having soany problems with it. The plug always comes out black, it has black smoke at idle. It falls over and bogs at WOT usually. The other day, I had a 195 main jet with the same pilot and it was running the best it had. I could actually get some WOT in.
Additionally, partial throttle-between. 1/4 and 3/4 feels amazing. I can feel the increase in power from the modifications and it pulls like a freight train.
I also tried a Chinese 32mm I got off Amazon. It was better at idle but I couldn't get much on the high end. Carb seemed a bit small for the engine.
I've checked valve lash, confirmed timing of the cam, changed to a fresh plug, checked the clearance between the coil and flywheel. I'm really at a loss right now as to what to do.
Arc rod
34mm mikuni kit from GPS
TWISTER 250 CAM
50lb Valve Springs
Header
40 series CVT
I have it geared and setup so it won't rev past 4500. Once I go to the next stage up, I will get a flywheel.
I think my issue is with the carb. I've been messing with jetting and no matter how lean I go, it still appears to be rich. I'm currently at a 190 main and 12.5 pilot jet. I ordered a 10 pilot but it isn't here yet.
I've seen people run these on stock engines so I'm very confused as to why I am having soany problems with it. The plug always comes out black, it has black smoke at idle. It falls over and bogs at WOT usually. The other day, I had a 195 main jet with the same pilot and it was running the best it had. I could actually get some WOT in.
Additionally, partial throttle-between. 1/4 and 3/4 feels amazing. I can feel the increase in power from the modifications and it pulls like a freight train.
I also tried a Chinese 32mm I got off Amazon. It was better at idle but I couldn't get much on the high end. Carb seemed a bit small for the engine.
I've checked valve lash, confirmed timing of the cam, changed to a fresh plug, checked the clearance between the coil and flywheel. I'm really at a loss right now as to what to do.
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