Inliners International Forums General Discussion Engines Carb Base Temperature?

I have a stock '67 250 with the original manifolds including a functioning heat valve. When I'm running at low throttle or extended idling the base of the carb is around 160°F and the engine will run kind of rough and lack power. If I'm running at highway speeds or right after a heat soak (i.e. stopping engine and restart a few minutes later), the carb base temp will be up around 200°F. The engine will run much smoother all the way up to 4500 RPM and have more power if the carb base temp is higher. What is a good operating temperature at the base of the carburetor? Do I have a weak heat valve spring?

Thanks,

Dan

Greetings Dan, I think 160 seems pretty good and the manifold is probably even hotter. Maybe the carb or the choke is a little off? Just a guess though.