Hey guys long time supra owner here, new to the forum. I have 1991 Supra Sunsport with 351W(Pro-tec converted) It was freshly rebuilt(block replaced) about a year ago and has 24hrs on the rebuild. I have been having an issue this season and I'm trying to narrow it down. The symptoms are: runs fine at normal idle, won't accelerate(above 800rpms) until up to operating temperature, bogs/chokes when giving any throttle at any temperature, occasionally back fires. If you careful and slow you can accelerate.
The carb was replaced last year and properly stored at the end of the season
I have been through the gas(replaced filter, new gas, ethanol treatment) I have replaced a couple vacuum hoses. Im wondering if it could be due air starvation(choking). The flame arrestor is really dirty. In the next few days I'm going to pressure wash the flame arrester and see what happens. Please let me know if you guys have any other ideas.