Hi Folks, running into an issue with a stumble upon acceleration and carbon fouled plugs. It's a new build for the whole motor, new carb (rebuilt by KP Carbs from the old Pony Carbs). Details and issue below:
Build
200ci, 30 over zero decked
VI Aluminum Head/Intake
YT Roller Rockers
Schneider 270/270 cam, 110 LSA 2* advance
Stock C4, stock converter
Approx 10:1 compression
Autolite 2100, 1.23v @ 356cfm currently 55f jets
Recurved DSII by WSA at 18 degrees advance
Issue
I tuned using a vac gauge for smoothest idle and highest vacuum, approx 14mmHg (decent cam, stock C4). I know I'm running rich based on carbon fouled plugs and some black smoke out of the exhaust. It idles in park fine around 850, but as soon as I drop it in gear the idle becomes very low and rough, sometimes sputtering and it wants to die. Some accelerator or adding some choke will help, but that's a bandaid. If I tap the accelerator, it will move and get up to speed (slowly). If I give it any more than 25-50% throttle, it sputters and dies.
I've checked the float, seems fine. Carb was rebuilt and restored so I'm not worried about internals being gummed up. I'll be installing an AFR gauge in the coming days, but I'm wondering if it's the jets. I've adjusted the air fuel screws, adjusted the accelerator pump (currently at the outside whole, and the second from the top) and tried different settings with nothing really helping. No vacuum leaks I can find, fresh gaskets on the carb mounting bracket to intake and gasket at the carb. I pulled the plugs today and they were all carbon fouled.
Other than jets, which I have a few coming my way, any other things I should be checking or potential culprits? I've done all my tuning and testing with the air cleaner off as well.
Build
200ci, 30 over zero decked
VI Aluminum Head/Intake
YT Roller Rockers
Schneider 270/270 cam, 110 LSA 2* advance
Stock C4, stock converter
Approx 10:1 compression
Autolite 2100, 1.23v @ 356cfm currently 55f jets
Recurved DSII by WSA at 18 degrees advance
Issue
I tuned using a vac gauge for smoothest idle and highest vacuum, approx 14mmHg (decent cam, stock C4). I know I'm running rich based on carbon fouled plugs and some black smoke out of the exhaust. It idles in park fine around 850, but as soon as I drop it in gear the idle becomes very low and rough, sometimes sputtering and it wants to die. Some accelerator or adding some choke will help, but that's a bandaid. If I tap the accelerator, it will move and get up to speed (slowly). If I give it any more than 25-50% throttle, it sputters and dies.
I've checked the float, seems fine. Carb was rebuilt and restored so I'm not worried about internals being gummed up. I'll be installing an AFR gauge in the coming days, but I'm wondering if it's the jets. I've adjusted the air fuel screws, adjusted the accelerator pump (currently at the outside whole, and the second from the top) and tried different settings with nothing really helping. No vacuum leaks I can find, fresh gaskets on the carb mounting bracket to intake and gasket at the carb. I pulled the plugs today and they were all carbon fouled.
Other than jets, which I have a few coming my way, any other things I should be checking or potential culprits? I've done all my tuning and testing with the air cleaner off as well.