BluePrint Engines B400KTKX SBC 400/500HP with TKX, Carbureted

This 400 build bolts a 5-speed TKX transmission behind a bigger carburetor than BluePrint's other 400 combos use, for a builder who wants more flow on a manual-shift engine. Output is unchanged at 500 horsepower, with the same forged crankshaft and pistons under a 10.3:1 compression ratio.

What it is built for

The larger 850 CFM double-pumper carburetor is the main difference from BluePrint's other carbureted 400 builds, intended for drivers who want more top-end carburetor flow paired with manual-transmission control. A dual-plane intake and polished front accessory drive carry over from the rest of the 400 lineup.

What to check before ordering

This TKX kit's clutch comes from McLeod's Super Street Pro single-disc line. A hydraulic throwout bearing, bellhousing, and billet flywheel are part of the package, with wide-ratio gearing suited to a manual-choke carbureted 400. A carburetor this size needs a properly sized fuel line feeding it, so plan your under-hood routing around the manual choke setup. For a California installation, this counts as an engine change rather than a factory replacement, so confirm it against the Bureau of Automotive Repairs requirements.

Common questions

What carburetor comes with this version? An 850 CFM Holley Double Pumper with a manual choke.

Is the compression ratio different from BluePrint's EFI 400? No, both run 10.3:1.

Is the horsepower the same as BluePrint's automatic 400? Yes, 510 lb-ft of torque either way.