Triple Black 73
Well-Known Member
You guys have been great in the past and wonder if y'all can help me again. I got a issue at WOT underload.
The engine revs up fast and smooth in neutral from idle all the way to red line. it's the same way on jack stands and in gear: fast and smooth. And I can hold it any RPM without a vibration.
However when underload there's a vibration at WOT. It just gets worst the faster the engine spins. If I had to put it in words it would be something like "vooooooom" without load and "voovoovoovoovoom" underload.
I had a bog going from part throttle to WOT which I was able to tune out with the idle mix and timing. Now I'm trying to dial out this WOT issue. It's always been there. The spark plugs look good. Maybe I don't have enough timing? I have no clue what spark knock sounds like so I can't tell you. Maybe I should I get a o2 sensor? I have a A/F gauge in the spare parts crate; I just need weld in a bung and wire it up. Maybe the stock 45 gph fuel pump can't supply the carb with enough fuel? I read that adjusting the floats help. I don't really don't know much about this old school stuff as it is still very new to me. But I want to learn everything I can about it.
Here's the setup in the '73 Charger:
The engine revs up fast and smooth in neutral from idle all the way to red line. it's the same way on jack stands and in gear: fast and smooth. And I can hold it any RPM without a vibration.
However when underload there's a vibration at WOT. It just gets worst the faster the engine spins. If I had to put it in words it would be something like "vooooooom" without load and "voovoovoovoovoom" underload.
I had a bog going from part throttle to WOT which I was able to tune out with the idle mix and timing. Now I'm trying to dial out this WOT issue. It's always been there. The spark plugs look good. Maybe I don't have enough timing? I have no clue what spark knock sounds like so I can't tell you. Maybe I should I get a o2 sensor? I have a A/F gauge in the spare parts crate; I just need weld in a bung and wire it up. Maybe the stock 45 gph fuel pump can't supply the carb with enough fuel? I read that adjusting the floats help. I don't really don't know much about this old school stuff as it is still very new to me. But I want to learn everything I can about it.
Here's the setup in the '73 Charger:
- 383 bored 60 over
- 452 heads
- 9:1 compression
- '72 Thermo-quad 800cfm carb
- Stock dual snorkel air cleaner
- Holley Street Dominator single plane intake
- Stock ignition box and coil
- MSD 8.5mm spark plug wires
- Bosch 4236 Platinum, Gap 0.035"
- Compcam Xtreme Energy XE256H
- 1-3/4" headers into 3" dual exhaust, no H-pipe
- Stock 45 gph fuel pump, 7/16 fuel line, no return
- Timing 12 degree initial, 38 all in
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