We tested a mild 489 BBC in an 83 Chevy K10 shortbed truck on a chassis dyno.  

It had 10:1compression, Aluminum GMPP oval port heads, Lunati hydraulic roller cam with 231@.050 duration and .600″ lift.

Dart single plane oval port BBC intake manifold with Volcano System Interface.  

The EFI was a FAST EZ-EFI, the original version set at 50 psi fuel pressure.  A/F ratios were always at the same targets and closed loop was on every time.  The ECU base tune was reset before every run to avoid the self learning changing the results.  

The exhaust was Hooker Competition headers with 1 3/4″ Primaries and 3″ collectors through Dual 3″ exhaust and Flowmaster 50 series “Big Block” Mufflers.

It was ran through a Turbo 400 transmission with 10″ Hughes Converter, an NP205 gear drive transfer case, and 14 Bolt full floating 1 ton axle with 4.10 gears.  Drivetrain loss was high in the 1 ton truck drivetrain.  

The tires and wheels were 36×14.5 swampers that weighed 112 lbs/corner.  They were swapped for some 31″ load range E LT tires for all testing shown because the swampers were showing a loss of 70 HP by themselves on that dyno, also the shaking of the tires at high speed causes oscillations in the power output in the upper RPM range(hence the wavy curve).   This engine is approximately 525-550 HP at the crank with over 600 lb-ft of torque. 

All runs were stopped just after peak power around 5200 RPM because the tires were not liking spinning at over 100 MPH and it was shaking the entire rig.  This offroad toy usually only sees about 70 MPH max on the road or the sand dunes.   

Call us to purchase the Intake, Fuel injection, Headers, etc for this setup.  

1983 Chevy K10 w/1 ton axles and 489 BBC

The output graphs with and without the Volcano Insert showed a gain of 10 HP and 9 lb-ft at peak at the rear wheels just by swapping in the regular tall Volcano!  And the power and TQ were higher through the entire measured RPM range!  This test was rain with the coolant temp around 200 F for both runs. 

If you run the same test again with the coolant temp around 170F for both runs it showed higher peak power for both, with lower midrange TQ and HP, and a lower difference in peak power with a gain around 5 HP @ 5,000 RPM.  However, it also showed massive gains with the Volcano in the lower RPM ranges, sometimes as much as 40 HP and 50 lb-ft around 4,000 RPM!