You've disabled the temperature-control system for the intake manifold. The heater air-duct temperature might increase by two degrees, but the fuel distribution is probably less-good due to less fuel being vaporized in the manifold.
Older SBC intakes were heated by the exhaust crossover under the plenum. This has exhaust gas in that area, but it's primarily for EGR, not manifold heating.
Having coolant run through the manifold also keeps oil from burning to the bottom of it, which was something of a problem with the exhaust-heated manifolds.
Older SBC intakes were heated by the exhaust crossover under the plenum. This has exhaust gas in that area, but it's primarily for EGR, not manifold heating.
Having coolant run through the manifold also keeps oil from burning to the bottom of it, which was something of a problem with the exhaust-heated manifolds.
