Monthly Archives: November 2014

380 Horsepower- 460 ft-lb Torque 383 Small Block Chevy

JMacPerformance built a mild street 383 Small Block Chevy.  The engine was intended for a 41 Ford pickup street rod that would be pulling a trailer, so the goal was to make as much Torque as possible while keeping mild street manners and daily reliability.

OLYMPUS DIGITAL CAMERA

The build starts with a standard 010 350 block that was given the usual bore and hone (with torque plate), decked, magnifluxed, and pressure tested. A balanced SCAT bottom end kit was added with KB hypereutectic dished pistons for a pump gas friendly 9/1 compression, 3.75 stroke cast steel crankshaft, 5.7″ connecting rods, and clevite bearings.

 OLYMPUS DIGITAL CAMERA  OLYMPUS DIGITAL CAMERA

A factory windage tray, Mellings HV oil pump, and 5 quart oil pan were added

OLYMPUS DIGITAL CAMERA

Knowing that torque was the goal I used a pair of Pro Topline Vortec style aftermarket heads. They were affordable, very high quality, and the Vortec design was intended to increase torque which fit this build perfectly. They were pocket ported and had stainless steel Ferrea valves added to ensure good flow numbers.

 OLYMPUS DIGITAL CAMERA OLYMPUS DIGITAL CAMERA

The valve train was controlled by a 264/270 Iskenderian Mega camshaft, lifters, valve springs, steel retainers, and clips.  Custom length one piece Comp Cams chrome moly push rods where used along with self-aligning full roller rockers.

OLYMPUS DIGITAL CAMERA Isky Racing Cams

Topping off the engine is a Edelbrock Vortec Air-Gap RPM Performer intake manifold, Edelbrock 750 Carburetor, and HEI distributor.

OLYMPUS DIGITAL CAMERA OLYMPUS DIGITAL CAMERAOLYMPUS DIGITAL CAMERA

Once bolted up to the dyno the usual procedures were used to ensure the camshaft was broken-in properly.  After a few pulls to the optimize timing and jetting we had 380 Horsepower @ 4900 RPM and 460 ft-lb Torque @ 3400.

The engine had over 400 ft-lb of torque from 2500 to 5000 RPM.  

  383 dyno sheet  383 dyno graph

This 383 has that high performance / muscle car sound without being over the top. It will work for any street rod, muscle car, or truck and with the pump gas friendly 9/1 compression it is mild enough to be used as a daily driver.