Jim Smart
July 1, 2003
Photos By: Julio Mayen

No. 5
Before the first pull, we made a minor fuel system change. We replaced the Wilson 1-inch four-hole spacer with a 1 1/4-inch open spacer and made no other changes. We gained 10.1 lb-ft of torque and 6.4 hp.

Cylinder HeadsAFR 185
Compression Ratio10.0:1
Intake ManifoldEdelbrock Performer RPM Air-Gap
Carburetor/Jetting/Adjustment650-cfm Race Demon w/spacer
Camshaft TypeComp Cams 282 Hydraulic Roller
Rocker-Arm Ratio1.6:1
Ignition Timing34 deg. BTDC (full advance)
Header Type & Size13/4-inch long-tube headers
ChangesSwitched to Wilson 11/4-inch open carburetor spacer
RPMPeak HPPeak TorqueBSFCAir/Fuel Ratio
5,000437.20.39513.09
6,100477.50.49711.05

No. 6
Before the sixth pull, we made a minor fuel/air adjustment and spun the crank again. This is what happened. We gained 8 hp and 0.7 lb-ft of torque.

Cylinder HeadsAFR 185
Compression Ratio10.0:1
Intake ManifoldEdelbrock Performer RPM Air-Gap
Carburetor/Jetting/Adjustment650-cfm Race Demon w/spacer
Camshaft TypeComp Cams 282 Hydraulic Roller
Rocker-Arm Ratio1.6:1
Ignition Timing34 deg. BTDC (full advance)
Header Type & Size13/4-inch long-tube headers
ChangesMinor carburetor adjustment
RPMPeak HPPeak TorqueBSFCAir/Fuel Ratio
5,000437.90.47511.61
6,300485.50.47311.88

No. 7
When 36 degrees of total advance didn't do it for us, we retarded the ignition timing to 32 degrees BTDC. We gained 2 lb-ft of torque and virtually no increase in horsepower. When you look at brake-specific fuel consumption (BSFC), there's essentially no change with adjustments to ignition timing.

Cylinder HeadsAFR 185
Compression Ratio10.0:1
Intake ManifoldEdelbrock Victor Jr.
Carburetor/Jetting/Adjustment650-cfm Race Demon w/spacer
Camshaft TypeComp Cams 282 Hydraulic Roller
Rocker-Arm Ratio1.6:1
Ignition Timing32 deg. BTDC (full advance)
Header Type & Size13/4-inch long-tube headers
ChangesRetard ignition timing to 32 degrees BTDC
RPMPeak HPPeak TorqueBSFCAir/Fuel Ratio
5,300439.90.40412.74
6,100483.30.48411.50

No. 8
Another 150-mile journey to Ontario witnessed Elvira's 331 back on Westech's dyno, for another shot at fame, and 500/420. Here's what happened on the first pull of the day.

Cylinder HeadsAFR 205
Compression Ratio10.0:1
Intake ManifoldEdelbrock Victor Jr.
Carburetor/Jetting/Adjustment650-cfm Race Demon w/spacer
Camshaft TypeComp Cams 282 Hydraulic Roller using
mechanical roller lifters to prevent valve float
Rocker-Arm Ratio1.7:1
Ignition Timing34 deg. BTDC (full advance)
Header Type & Size13/4-inch long-tube headers
ChangesSwitch to AFR 205 heads, 1.7:1 rocker arms
for greater valve lift, mechanical roller lifters to prevent float. Back to Edelbrock Victor Jr.
Melling standardvolume oil pump. Meziere electric water pump.Royal Purple synthetic 5W-30 oil.
RPMPeak HPPeak TorqueBSFCAir/Fuel Ratio
5,700433.20.47911.20
6,700505.90.46812.48

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